In mid-October 2022 I enjoyed a rare run of five clear and mild nights in the Rocky Mountains for shooting nightscapes of the stars. Here’s a portfolio … and a behind-the-scenes look at its making.
Getting two perfectly clear nights in a row is unusual in the mountains. Being treated to five is a rare treat. Indeed, had I started my shooting run earlier in the week I could have enjoyed even more of the string of cloudless nights in October, though under a full Moon. But five was wonderful, allowing me to capture some of the scenes that had been on my shot list for the last few years.
Here is a portfolio of the results, from five marvelous nights in Banff and Jasper National Parks, in Alberta, Canada.
For the photographers, I also provide some behind-the-scenes looks at the planning and shooting techniques, and of my processing steps.
Night One — Peyto Lake, Banff National Park
Peyto Lake, named for pioneer settler and trail guide Bill Peyto who had a cabin by the lakeshore, is one of several iconic mountain lakes in Banff. Every tour bus heading along the Icefields Parkway between Banff and Jasper stops here. By day is it packed. By night I had the newly constructed viewpoint all to myself.
I shot the classic view north in deep twilight, with the stars of Ursa Major and the Big Dipper low over the lake, as they are in autumn. A show of Northern Lights would have been ideal, but I was happy to settle for just the stars.
The night was perfect, not just for the clarity of the sky but also the timing. The Moon was just past full, so was rising in late evening, leaving a window of time between the end of twilight and moonrise when the sky would be dark enough to capture the Milky Way. Then shortly after, the Moon would come up, lighting the peaks with golden moonlight — alpenglow, but from the Moon not Sun.
The above is blend of two panoramas, each of seven segments, the first for the sky taken when the sky was dark, using a star tracker to keep the stars pinpoints. The second for the ground I shot a few minutes later at moonrise with no tracking, to keep the ground sharp. I show below how I blended the two elements.
To plan such shots I use the apps The Photographer’s Ephemeris (TPE) and its companion app TPE 3D. The screen shot above at left shows the scene in map view for the night in question, with the Big Dipper indicated north over the lake and the line of dots for the Milky Way showing it to the southwest over Peyto Glacier. Tap or click on the images for full-screen versions.
Switch to TPE 3D and its view at right above simulates the scene you’ll actually see, with the Milky Way over the mountain skyline just as it really appeared. The app even faithfully replicates the lighting on the peaks from the rising Moon. It is an amazing planning tool.
On the drive back from Peyto Lake to Saskatchewan River Crossing I stopped at another iconic spot, the roadside viewpoint for Mt. Cephren at Waterfowl Lakes. By this time, the Moon was well up and fully illuminating the peak and the sky, but still leaving the foreground dark. The sky is blue as it is by day because it is lit by moonlight, which is just sunlight reflecting off a perfectly neutral grey rock, the Moon!
This is from a set of untracked camera-on-tripod shots using short 30-second exposures.
Night Two — Pyramid Lake, Jasper National Park
By the next night I was up in Jasper, a destination I had been trying to revisit for some time. But poor weather prospects and forest fire smoke had kept me away in recent years.
The days and nights I was there coincided with the first weekend of the annual Jasper Dark Sky Festival. I attended one of the events, the very enjoyable Aurora Chaser’s Retreat, with talks and presentations by some well-known chasers of the Northern Lights. Attendees had come from around North America.
On my first night in Jasper I headed up to Pyramid Lake, a favorite local spot for stargazing and night sky photography, particularly from the little island connected to the “mainland” by a wooden boardwalk. Lots of people were there quietly enjoying the night. I shared one campfire spot with several other photographers also shooting the Milky Way over the calm lake before moonrise.
A little later I moved to the north end of Pyramid Island for the view of the Big Dipper over Pyramid Mountain, now fully lit by the rising waning Moon, and with some aspens still in their autumn colours. A bright meteor added to the scene.
Night Three — Athabasca River Viewpoint, Jasper National Park
For my second night in Jasper, I ventured back down the Icefields Parkway to the “Goats and Glaciers” viewpoint overlooking the Athabasca River and the peaks of the Continental Divide.
As I did at Peyto Lake, I shot a panorama (this one in three sections) for the sky before moonrise with a tracker. I then immediately shot another three-section panorama, now untracked, for the ground while it was still lit just by starlight under a dark sky. I then waited an hour for moonrise and shot a third panorama to add in the golden alpenglow on the peaks. So this is a time-blend, bending reality a bit. See my comments below!
Night Four — Edith Lake, Jasper National Park
With a long drive back to Banff ahead of me the next day, for my last night in Jasper I stayed close to town for shots from the popular Edith Lake, just up the road from the posh Jasper Park Lodge. Unlike at Pyramid Lake, I had the lakeshore to myself.
This would be a fabulous place to catch the Northern Lights, but none were out this night. Instead, I was content to shoot scenes of the northern stars over the calm lake and Pyramid Mountain.
The Moon was now coming up late, so the shots above are both in darkness with only starlight providing the illumination. Well, and also some annoying light pollution from town utility sites off the highway. Jasper is a Dark Sky Preserve, but a lot of the town’s street and utility lighting remains unshielded.
Night Five — Lake Louise, Banff National Park
On my last night I was at Lake Louise, as the placement of the Milky Way would be perfect.
There’s no more famous view than this one, with Victoria Glacier at the end of the blue-green glacial lake. Again, by day the site is thronged with people and the parking lot full by early morning.
By night, there were just a handful of other photographers on the lakeshore, and the parking lot was nearly empty. I could park right by the walkway up to the lake.
Again, TPE and TPE 3D told me when the Milky Way would be well-positioned over the lake and glacier, so I could complete the untracked ground shots first, to be ready to shoot the tracked sky segments by the time the Milky Way had turned into place over the glacier.
This image is also a panorama but a vertical one, made primarily of three untracked segments for the ground and seven tracked segments for the sky, panning up from the horizon to past the zenith overhead, taking in most of the summer and autumn Milky Way from Serpens up to Cassiopeia.
As readers always want to know what gear I used, I shot all images on all nights with the 45-megapixel Canon R5 camera and Canon RF15-35mm lens, with exposures of typically 1 to 3 minutes each at ISOs of 800 to 1600. I had other cameras and lenses with me but never used them.
I use the Mini with a V-Plate designed by nightscape photographer Alyn Wallace and sold by Move-Shoot-Move. It is an essential aid to taking tracked panoramas, as it allows me to turn the camera horizontally manually from one pan segment to the next while the camera is tracking the stars. It’s easy to switch the tracker on (for the sky) and off (for the ground). The Mini tracks quite accurately and reliably. Turn it on and you can be sure it is tracking.
For those who are interested, here’s a look at how I processed and assembled the images, using the Peyto Lake panorama as an example. This is not a thorough tutorial, but shows the main steps involved. Tap or click on an image to download a full-size version.
I first develop all the raw files (seven here) in Adobe Camera Raw, applying identical settings to make them look best for what they are going to contribute to the final blend, in this case, for the tracked sky with pinpoint stars and the Milky Way.
Camera Raw (as does Adobe’s Lightroom) has an excellent Merge to Panorama function which usually works very well on such scenes. This shows the stitched sky panorama, created with one click.
I develop and stitch the untracked ground segments to look their best for revealing details in the landscape, overexposing the sky in the process. Stars are also trailed, from the long exposures needed for the dark ground. No matter – these will be masked out.
This shows the stack of images now in Adobe Photoshop, but here revealing just the layer for the sky panorama and its associated adjustment layers to further tweak color and contrast. I often add noise reduction as a non-destructive “smart filter” applied to the “smart object” image layer. See my review of noise reduction programs here.
This shows just the ground panorama layer, again with some adjustment and retouching layers dedicated to this portion of the image.
The sky has to be masked out of the ground panorama, to reveal the sky below. The Select Sky command in Photoshop usually works well, or I just use the Quick Selection tool and then Select and Mask to refine the edge. That method can be more accurate.
Aligning the two panoramas requires manually nudging the untracked ground, up in this case, to hide the blurred and dark horizon from the tracked sky panorama. Yes, we move the earth! The sky usually also requires some re-touching to clone out blurred horizon bits sticking up. Dealing with trees can be a bit messy!
The result is the scene above with both panorama layers and the masks turned on. While this now looks almost complete, we’re not done yet.
Local adjustments like Dodge and Burn (using a neutral grey layer with a Soft Light blend mode) and some luminosity masks tweak the brightness of portions of the scene for subtle improvements, to emphasize some areas while darkening others. It’s what film photographers did in the darkroom by waving physical dodging and burning tools under the enlarger.
I add finishing touches with some effect plug-ins: Radiant Photo added some pop to the ground, while Luminar Neo added a soft “Orton glow” effect to the sky and slightly to the ground.
All the adjustments, filters, and effects are non-destructive so they can be re-adjusted later, when upon further inspection with fresh eyes I realize something needs work.
Was It Photoshopped?
I hope my look behind the curtains was of interest. While these types of nightscapes taken with a tracker, and especially multi-segment panoramas, do produce dramatic images, they do require a lot of processing at the computer.
Was it “photoshopped?” Yes. Was it faked? No. The sky really was there over the scene you see in the image. However, the long exposures of the camera do reveal more details than the eye alone can see at night — that is the essence of astrophotography.
My one concession to warping reality is in the time-blending — the merging of panoramas taken 30 minutes to an hour apart. I’ll admit that does push my limits for preferring to record real scenes, and not fabricate them (i.e. “photoshop” them in common parlance).
But at this shoot on these marvelous nights, making use of the perfectly timed moonrises was hard to resist!
In a detailed technical blog I compare six AI-based noise reduction programs for the demands of astrophotography. Some can work wonders. Others can ruin your image.
Over the last two years we have seen a spate of specialized programs introduced for removing digital noise from photos. The new generation of programs use artificial intelligence (AI), aka machine learning, trained on thousands of images to better distinguish unwanted noise from desirable image content.
At least that’s the promise – and for noisy but normal daytime images they do work very well.
But in astrophotography our main subjects – stars – can look a lot like specks of pixel-level noise. How well can each program reduce noise without eliminating stars or wanted details, or introducing odd artifacts, making images worse.
To find out, I tested six of the new AI-based programs on real-world – or rather “real-sky” – astrophotos. Does one program stand out from the rest for astrophotography?
NOTE: All the images are full-resolution JPGs you can tap or click on to download for detailed inspection. But that does make the blog page slow to load initially. Patience!
The new AI-trained noise reduction programs can indeed eliminate noise better than older non-AI programs, while leaving fine details untouched or even sharpening them.
Of the group tested, the winner for use on just star-filled images is a specialized program for astrophotography, NoiseXTerminator from RC-Astro.
For nightscapes and other images, Topaz DeNoise AI performed well, better than it did in earlier versions that left lots of patchy artifacts, something AI programs can be prone to.
While ON1’s new NoNoise AI 2023 performed fine, it proved slightly worse in some cases than its earlier 2022 version. Its new sharpening routine needs work.
Other new programs, notably Topaz Photo AI and Luminar’s Noiseless AI, also need improvement before they are ready to be used for the rigours of astrophotography.
For reasons explained below, I would not recommend DxO’s PureRAW2.
As described below, while some of the programs can be used as stand-alone applications, I tested them all as plug-ins for Photoshop, applying each as a smart filter applied to a developed raw file brought into Photoshop as a Camera Raw smart object.
Most of these programs state that better results might be obtainable by using the stand-alone app on original raw files. But for my personal workflow I prefer to develop the raw files with Adobe Camera Raw, then open those into Photoshop for stacking and layering, applying any further noise reduction or sharpening as non-destructive smart filters.
Many astrophotographers also choose to stack unedited original images with specialized stacking software, then apply further noise reduction and editing later in the workflow. So my workflow and test procedures reflect that.
However, the exception is DxO’s PureRAW2. It can work only on raw files as a stand-alone app, or as a plug-in from Adobe Lightroom. It does not work as a Photoshop plug-in. I tested PureRAW2 by dropping raw Canon .CR3 files onto the app, then exporting the results as raw DNG files, but with the same settings applied as with the other raw files. For the nightscape and wide-field images taken with lenses in DxO’s extensive database, I used PureRAW’s lens corrections, not Adobe’s.
As shown above, I chose three representative images:
A nightscape with star trails and a detailed foreground, at ISO 1600.
A wide-field deep-sky image at ISO 1600 with an 85mm lens, with very tiny stars.
A close-up deep-sky image taken with a telescope and at a high ISO of 3200, showing thermal noise hot pixels.
Each is a single image, not a stack of multiple images.
Before applying the noise reduction, the raw files received just basic color corrections and a contrast boost to emphasize noise all the more.
In the test results for the three images, I show the original raw image, plus a version with noise reduction and sharpening applied using Adobe Camera Raw’s own sliders, with luminance noise at 40, color noise at 25, and sharpening at 25.
I use this as a base comparison, as it has been the noise reduction I have long applied to images. However, ACR’s routine (also found in Adobe Lightroom) has not changed in years. It is good, but it is not AI.
The new smart AI programs should improve upon this. But do they?
I have refrained from providing prices and explaining buying options, as frankly some can be complex!
For those details and for trial copies, go to the software’s website by clicking on the link in the header product names below.
All programs are available for Windows and MacOS. I tested the latter versions.
I have not provided tutorials on how to use the software; I have just reported on their results. For trouble-shooting their use, please consult the software company in question.
ON1’s main product is the Lightroom/Photoshop alternative program called ON1 Photo RAW, which is updated annually to major new versions. It has full cataloging options like Lightroom and image layering like Photoshop. Its Edit module contains the NoNoise AI routine. But NoNoise AI can be purchased as a stand-alone app that also installs as a plug-in for Lightroom and Photoshop. It’s what I tested here. The latest 2023 version of NoNoise AI added ON1’s new Tack Sharp AI sharpening routine.
This program has proven very popular and has been adopted by many photographers – and astrophotographers – as an essential part of an editing workflow. It performs noise reduction only, offering a choice of five AI models. Auto modes can choose the models and settings for you based on the image content, but you can override those by adjusting the strength, sharpness, and recovery of original detail as desired.
A separate program, Topaz Sharpen AI, is specifically for image sharpening, but I did not test it here. Topaz Gigapixel AI is for image resizing.
In 2022 Topaz introduced this new program which incorporates the trio of noise reduction, sharpening and image resizing in one package. Like DeNoise, Sharpen and Gigapixel, Photo AI works as a stand-alone app or as a plug-in for Lightroom and Photoshop. Photo AI’s Autopilot automatically detects and applies what it thinks the image needs. While it is possible to adjust settings, Photo AI offers much less control than DeNoise AI and Topaz’s other single-purpose programs.
As of this writing in November 2022 Photo AI is enjoying almost weekly updates, and seems to be where Topaz is focusing its development and marketing effort.
Unlike the other noise reduction programs tested here, Luminar Neo from the software company Skylum is a full-featured image editing program, with an emphasis on one-click AI effects. One of those is the new Noiseless AI, available as an extra-cost extension to the main Neo program, either as a one-time purchase or by annual subscription. Noiseless AI cannot be purchased on its own. However, Neo with most of its extensions does work as a plug-in for Lightroom and Photoshop.
Being new, Luminar Neo is also updated frequently, with more extensions coming in the next few months.
Like ON1, DxO makes a full-featured alternative to Adobe’s Lightroom for cataloging and raw developing called DxO PhotoLab, in version 6 as of late 2022. It contains DxO’s Prime and DeepPrime noise reduction routines. However, as with ON1, DxO has spun off just the noise reduction and lens correction parts of PhotoLab into a separate program, PureRAW2, which runs either as a stand-alone app or as a plug-in for Lightroom – but not Photoshop, as PureRAW works only on original raw files.
Unlike all the other programs, PureRAW2 offers essentially no options to adjust settings, just the option to apply, or not, lens corrections, and to choose the output format. For this testing I applied DeepPrime and exported out to DNG files.
Unlike the other programs tested, NoiseXTerminator from astrophotographer Russell Croman is designed specifically for deep-sky astrophotography. It installs as a plug-in for Photoshop or Affinity Photo, but not Lightroom. It is also available under the same purchased licence as a “process” for PixInsight, an advanced program popular with astrophotographers, as it is designed just for editing deep-sky images.
I tested the Photoshop plug-in version of Noise XTerminator. It receives occasional updates to both the actual plug-in and separate updates to the AI module.
Version tested: 1.1.2, AI model 2
As with the other test images, the panels show a highly magnified section of the image, indicated in the inset. I shot the image of Lake Louise in Banff, Alberta with a Canon RF15-35mm lens on a 45-megapixel Canon R5 camera at ISO 1600.
Adobe Camera Raw’s basic noise reduction did a good job, but like all general routines it does soften the image as a by-product of smoothing out high-ISO noise.
ON1 NoNoise 2023 retained landscape detail better than ACR but softened the star trails, despite me adding sharpening. It also produced a somewhat patchy noise smoothing in the sky. This was with Luminosity backed off to 75 from the auto setting (which always cranks up the level to 100 regardless of the image), and with the Tack Sharp routine set to 40 with Micro Contrast at 0. It left a uniform pixel-level mosaic effect in the shadow areas. Despite the new Tack Sharp option, the image was softer than with last year’s NoNoise 2022 version (not shown here as it is no longer available) which produced better shadow results.
Topaz DeNoise AI did a better job than NoNoise retaining the sharp ground detail while smoothing noise, always more obvious in the sky in such images. Even so, it also produced some patchiness, with some areas showing more noise than others. This was with the Standard model set to 40 for Noise and Sharpness, and Recover Details at 75. I show the other model variations below.
Topaz Photo AI did a poor job, producing lots of noisy artifacts in the sky and an over-sharpened foreground riddled with colorful speckling. It added noise. This was with the Normal setting and the default Autopilot settings.
Noiseless AI in Luminar Neo did a decent job smoothing noise while retaining, indeed sharpening ground detail without introducing ringing or colorful edge artifacts. The sky was left with some patchiness and uneven noise smoothing. This was with the suggested Middle setting (vs Low and High) and default levels for Noise, Detail and Sharpness. However, I do like Neo (and Skylum’s earlier Luminar AI) for adding other finishing effects to images such as Orton glows.
DxO PureRAW2 did smooth noise very well while enhancing sharpness quite a lot, almost too much, though it did not introduce obvious edge artifacts. Keep in mind it offers no chance to adjust settings, other than the mode – I used DeepPrime vs the normal Prime. Its main drawback is that in making the conversion back to a raw DNG image it altered the appearance of the image, in this case darkening the image slightly. It also made some faint star trails look wiggly!
Noise XTerminator really smoothed out the sky, and did so very uniformly without doing much harm to the star trails. However, it smoothed out ground detail unacceptably, not surprising given its specialized training on stars, not terrestrial content.
Conclusion: For this image, I’d say Topaz DeNoise AI did the best, though not perfect, job.
This was surprising, as tests I did with earlier versions of DeNoise AI showed it leaving many patchy artifacts and colored edges in places. Frankly, I was put off using it. However, Topaz has improved DeNoise AI a lot.
Why it works so well, when Topaz’s newer program Photo AI works so poorly is hard to understand. Surely they use the same AI code? Apparently not. Photo AI’s noise reduction is not the same as DeNoise AI.
Similarly, ON1’s NoNoise 2023 did a worse job than their older 2022 version. One can assume its performance will improve with updates. The issue seems to be with the new Tack Sharp addition.
NoiseXTerminator might be a good choice for reducing noise in just the sky of nightscape images. It is not suitable for foregrounds.
WIDE-FIELD IMAGE TEST
I shot this image of Andromeda and Triangulum with an 85mm Rokinon RF lens on the 45-megapixel Canon R5 on a star tracker. Stars are now points, with small ones easily mistaken for noise. Let’s see how the programs handle such an image, zooming into a tiny section showing the galaxy Messier 33.
Adobe Camera Raw’s noise and sharpening routines do take care of the worst of the luminance and chrominance noise, but inevitably leave some graininess to the image. This is traditionally dealt with by stacking multiple sub-exposures.
ON1 NoNoise 2023 did a better job than ACR, smoothing the worst of the noise and uniformly, without leaving uneven patchiness. However, it did soften star images, almost like it was applying a 1- or 2-pixel gaussian blur, adding a slight hazy look to the image. And yet the faintest stars that appeared as just perceptible blurs in the original image were sharpened to one- or two-pixel points. This was with only NoNoise AI applied, and no Tack Sharp AI. And, as I show below, NoNoise’s default “High Detail” option introduced with the 2022 version and included in the 2023 edition absolutely destroys star fields. Avoid it.
Topaz DeNoise AI did a better job than Camera Raw, though it wasn’t miles ahead. This was with the Standard setting. Its Low Light and Severe models were not as good, surprising as you might think one of those choices would be the best for such an image. It pays to inspect Topaz’s various models’ results. Standard didn’t erase stars; it actually sharpened the fainter ones, almost a little too much, making them look like specks of noise. Playing with Enhance Sharpness and Recover Detail didn’t make much difference to this behavior.
Topaz Photo AI again performed poorly. Its Normal mode left lots of noise and grainy artifacts. While its Strong mode shown here did smooth background noise better, it softened stars, wiping out the faint ones and leaving colored edges on the brighter ones.
Noiseless AI in Luminar Neo did smooth fine noise somewhat, better than Camera Raw, but still left a grainy background, though with the stars mostly untouched in size and color.
DxO PureRAW2did eliminate noise quite well, while leaving even the faintest stars intact, unlike with the deep-sky image below, which is odd. However, it added some dark halos to bright stars from over-sharpening. And, as with the nightscape example, PureRAW’s output DNG was darker than the raw that went in. I don’t want noise reduction programs altering the basic appearance of an image, even if that can be corrected later in the workflow.
Noise XTerminator performed superbly, as expected – after all, this is the subject matter it is trained to work on. It smoothed out random noise better than any of the other programs, while leaving even the faintest stars untouched, in fact sharpening them slightly. Details in the little galaxy were also unharmed.
Conclusion: The clear winner was NoiseXTerminator.
Topaz DeNoise was a respectable second place, performing better than it had done on such images in earlier versions. Even so, it did alter the appearance of faint stars which might not be desirable.
ON1 NoNoise 2023 also performed quite well, with its softening of brighter stars yet sharpening of fainter ones perhaps acceptable, even desirable for an effect.
TELESCOPIC DEEP-SKY TEST
I shot this image of the NGC 7822 complex of nebulosity with a SharpStar 61mm refractor, using the red-sensitive 30-megapixel Canon Ra and with a narrowband filter to isolate the red and green light of the nebulas.
Again, the test image is a single raw image developed only to re-balance the color and boost the contrast. No dark frames were applied, so the 8-minute exposure at ISO 3200 taken on a warm night shows thermal noise as single “hot pixel” white specks.
Adobe Camera Raw did a good job smoothing the worst of the noise, suppressing the hot pixels but only by virtue of it softening all of the image slightly at the pixel level. However, it leaves most stars intact.
ON1 NoNoise 2023 also did a good job smoothing noise while also seeming to boost contrast and structure slightly. But as in the wide-field image, it did smooth out star images a little, though somewhat photogenically, while still emphasizing the faintest stars. This was with no sharpening applied and Luminosity at 60, down from the default 100 NoNoise applies without fail. One wonders if it really is analyzing images to produce optimum settings. With no Tack Sharp sharpening applied, the results on this image with NoNoise 2023 looked identical to NoNoise 2022.
Topaz DeNoise AI did another good job smoothing noise, while leaving most stars unaffected. However, the faintest stars and hot pixels were sharpened to be more visible tiny specks, perhaps too much, even with Sharpening at its lowest level of 1 in Standard mode. Low Light and Severe modes produced worse results, with lots of mottling and unevenness in the background. Unlike NoNoise, at least its Auto settings do vary from image to image, giving you some assurance it really is responding to the image content.
Topaz Photo AI again produced unusable results. Its Normal modes produced lots of mottled texture and haloed stars. Its Strong mode shown here did smooth noise better, but still left lots of uneven artifacts, like DeNoise AI did in its early days. It certainly seems like Photo AI is using old hand-me-down code from DeNoise AI.
Noiseless AI in Luminar Neo did smooth noise but unevenly, leaving lots of textured patches. Stars had grainy halos and the program increased contrast and saturation, adjustments usually best left for specific adjustment layers dedicated to the task.
DxO PureRAW2 did smooth noise very well, including wiping out the faintest specks from hot pixels, but it also wiped out the faintest stars, I think unacceptably and more than other programs like DeNoise AI. For this image it did leave basic brightness alone, likely because it could not apply lens corrections to an image taken with unknown optics. However, it added an odd pixel-level mosaic-like effect on the sky background, again unacceptable.
Noise XTerminator did a great job smoothing random noise without affecting any stars or the nebulosity. The Detail level of 20 I used actually emphasized the faintest stars, but also the hot pixel specks. NoiseXTerminator can’t be counted on to eliminate thermal noise; that demands the application of dark frames and/or using dithering routines to shift each sub-frame image by a few pixels when autoguiding the telescope mount. Even so, Noise XTerminator is so good users might not need to take and stack as many images.
Conclusion: Again, the winner was NoiseXTerminator.
Deep-sky photographers have praised “NoiseX” for its effectiveness, either when applied early on in a PixInsight workflow or, as I do in Photoshop, as a smart filter to the base stacked image underlying other adjustment layers.
Topaz DeNoise is also a good choice as it can work well on many other types of images. But again, play with its various models and settings. Pixel peep!
ON1 NoNoise 2023 did put in a respectable performance here, and it will no doubt improve – it had been out less than a month when I ran these tests.
Based on its odd behavior and results in all three test images I would not recommend DxO’s PureRAW2. Yes, it reduces noise quite well, but it can alter tone and color in the process, and add strange pixel-level mosaic artifacts.
COMPARING DxO and TOPAZ OPTIONS
DxO and Topaz DeNoise AI offer the most choices of AI models and strength of noise reduction. Here I compare:
Topaz DeNoise AI on the nightscape image using three of its models: Standard (which I used in the comparisons above), plus Low Light and Severe. These show how the other models didn’t do as good a job.
The set below also compares DeNoise AI to Topaz’s other program, Photo AI, to show how poor a job it is doing in its early form. Its Strong mode does smooth noise but over-sharpens and leaves edge artifacts. Yes, Photo AI is one-click easy to use, but produces bad results – at least on astrophotos.
As of this writing DxO’s PureRAW2 offers the Prime and newer DeepPrime AI models – I used DeepPrime for my tests.
However, DxO’s more expensive and complete image processing program, PhotoLab 6, also offers the even newer DeepPrimeXD model, which promises to preserve or recover even more “Xtra Detail” over the DeepPrime model. As of this writing, the XD mode is not offered in PureRAW2. Perhaps that will wait for PureRAW3, no doubt a paid upgrade.
The set above compares the three noise reduction models of DxO’s PhotoLab 6. DeepPrime does do a better job than Prime. DeepPrimeXD does indeed sharpen detail more, but in this example it is too sharp, showing artifacts, especially in the sky where it is adding structures and textures that are not real.
However, when used from within PhotoLab 6, the DeepPrime noise reduction becomes more usable. PhotoLab is then being used to perform all the raw image processing, so PureRAW’s alteration of color and tone is not a concern. Conversely, it can also output raw DNGs with only noise reduction and lens corrections applied, essentially performing the same tasks as PureRAW. If you have PhotoLab, you don’t need PureRAW.
COMPARING AI TO OLDER NON-AI PROGRAMS
The new generation of AI-based programs have garnered all the attention, leaving older stalwart noise reduction programs looking a little forlorn and forgotten.
Here I compare Camera Raw and two of the best of the AI programs, Topaz DeNoise AI and NoiseXTerminator, with two of the most respected of the “old-school” non-AI programs:
Dfine2, included with the Nik Collection of plug-ins sold by DxO (shown above), and
Reduce Noise v9 sold by Neat Image (shown below).
I tested both by using them in their automatic modes, where they analyze a section or sections of the image and adjust the noise reduction accordingly, but then apply that setting uniformly across the entire image. However, both allow manual adjustments, with Neat Image’s Reduce Noise offering a bewildering array of technical adjustments.
How do these older programs stack up to the new AI generation? Here are comparisons using the same three test images.
In the nightscape image, Nik Dfine2 and Neat Image’s Reduce Noise did well, producing uniform noise reduction with no patchiness. But the results weren’t significantly better than with Adobe Camera Raw’s built-in routine. Like ACR, both non-AI programs did smooth detail in the ground, compared to DeNoise AI which sharpened the mountain details.
In the tracked wide-field image, the differences were harder to distinguish. None performed up to the standard of Noise XTerminator, with both Nik Dfine2 and Neat Image softening stars a little compared to DeNoise AI.
In the telescopic deep-sky image, all programs did well, though none matched NoiseXTerminator. None eliminated the hot pixels. But Nik Dfine2 and Neat Image did leave wanted details alone, and did not alter or eliminate desired content. However, they also did not eliminate noise as well as did Topaz DeNoise AI or NoiseXTerminator.
The AI technology does work!
YOUR RESULTS MAY VARY
I should add that the nature of AI means that the results will certainly vary from image to image.
In addition, with many of these programs offering multiple models and settings for strength and sharpening, results even from the same program can be quite different. In this testing I used either the program’s auto defaults or backed off those defaults where I thought the effect was too strong and detrimental to the image.
Software is also a constantly moving target. Updates will alter how these programs perform, we hope for the better. For example, two days after I published this test, ON1 updated NoNoise AI to v17.0.2 with minor fixes and improvements.
And do remember I’m testing on astrophotos, and pixel peeping to the extreme. Rave reviews claiming how well even the poor performers here work on “normal” images might well be valid.
This is all by way of saying, your mileage may vary!
So don’t take my word for it. Most programs (Luminar Neo is an exception) are available as free trial copies to test out on your astro-images and in your preferred workflow. Test for yourself. But do pixel peep. That’s where you’ll see the flaws.
WHAT ABOUT ADOBE?
In the race for AI supremacy, one wonders where Adobe is in the field.
In the last couple of years Adobe has introduced several amazing and powerful “Neural Filters” into Photoshop, which work wonders with one click. And Lightroom and Camera Raw have received powerful AI-based selection and masking tools far ahead of most of the competition, with only Luminar Neo and ON1 Photo RAW coming close with similar auto-select capabilities.
But AI Noise Reduction? You think it would be a high priority.
A neural filter for Noise Reduction is on Adobe’s Wait List for development, so perhaps we will see something in the next few months from Adobe to compete with the AI offerings of Topaz, ON1 and Luminar/Skylum.
Until then we have lots of choices for third party programs that all improve with every update. I hope this review has helped you make a choice.
For once I was able to watch a total eclipse of the Moon under clear skies from home. Good thing, as a snowstorm would have made travel a challenge.
On November 8, 2022 the Full Moon once again passed through the umbral shadow of the Earth, as it has done at six-month intervals for the last two years. The Moon turned deep red for almost an hour and a half.
This was to be the last total eclipse of the Moon visible from anywhere in the world until March 14, 2025.
However, in the days leading up to the eclipse weather prospects looked poor. The worse snowstorm — indeed the first major snowstorm for my area — was forecast for the day before the eclipse, November 7. Of course!
For all the lunar eclipses in the last decade visible from my area, I have had to chase to find clear skies, perhaps a couple of hours away or a half day’s drive away. I documented those expeditions in previous posts, the latest of which is here for the May 15, 2022 total eclipse. In all cases I was successful.
However, just once it would be nice to be able to stay home. The last “TLE” I was able to watch from home was on December 21, 2010. It had been a long decade of lunar eclipse chasing!
But, it looked like another chase might be needed. Weather maps showed possible clear skies to the west and south of me on eclipse night. But cloud over me.
The problem was with six inches of new snow having fallen and temperatures forecast to be in the minus 20s Celsius, any drive to a remote site was going to be unwise, especially at 3 am for the start of the eclipse in my time zone in Alberta.
I decided to — indeed was more or less forced to — stay put at home and hope for the best. So this was the “snowbound eclipse!”
Luckily, as the snowstorm receded east, clear skies followed, providing better conditions than I had expected. What a pleasure it was watching this eclipse from the comfort of home. While operating camera gear at -25° C was still a challenge, at least I could retreat inside to warm up.
The view with the naked eye of the red Moon set in the winter sky was unforgettable. And the views though binoculars were, as always, the best for showing off the subtle colour gradations across the lunar disk.
As has been the tradition at the last few eclipses, I shot a souvenir selfie to show I was really there enjoying the eclipse.
A bonus was the appearance of some Northern Lights during totality. As the bright Moon dimmed during its passage into Earth’s umbral shadow, darkening the sky, the aurora began to appear to the north, opposite the eclipsed Moon.
Not a great display, but it was the first time I can recall seeing aurora during a lunar eclipse.
My parting view and photo was of the now partially eclipsed (and here overexposed) Moon emerging from the shadow and shining right down my rural snowbound driveway.
It was a perfect last look from home of a sight we won’t see again for two and half years.
In a detailed review, I test a “holy trinity” of premium Canon RF zoom lenses, with astrophotography the primary purpose.
In years past, zoom lenses were judged inferior to fixed-focal length “prime” lenses for the demands of astrophotography. Stars are the severest test of a lens, revealing optical aberrations that would go unnoticed in normal images, or even in photos of test charts. Many older zooms just didn’t cut it for discerning astrophotographers, myself included.
The new generation of premium zooms for mirrorless cameras, from Canon, Nikon and Sony, are dispelling the old wisdom that primes are better than zooms. The new zooms’ optical performance is proving to be as good, if not better than the older generation of prime lenses for DSLR cameras, models often designed decades ago.
The shorter lens-to-sensor “flange distance” offered by mirrorless cameras, along with new types of glass, provide lens designers more freedom to correct aberrations, particularly in wide-angle lenses.
While usually slower than top-of-the-line primes, the advantage of zoom lenses is their versatility for framing and composing subjects, great for nightscapes and constellation shots. It’s nice to have the flexibility of a zoom without sacrificing the optical quality and speed so important for astrophotography. Can we have it all? The new zooms come close to delivering.
A good thing, because with Canon we have little choice! For top-quality glass in wide-angle focal lengths at least, zooms are the only choice for their mirrorless R cameras. As of this writing in late 2022, Canon has yet to release any premium primes for their RF mount shorter than 50mm. Rumours are a 12mm, 24mm, 28mm, and 35mm are coming! But when?
The three zooms I tested are all “L” lenses, designating them as premium-performance models. I have not tested any of Canon’s “economy” line of RF lenses, such as their 24mm and 35mm Macro STM primes. Tests I’ve seen suggest they don’t offer the sharpness I desire for most astrophotography.
Contributing to the lack of choice, top-quality third-party lenses from the likes of Sigma (such as their new 20mm and 24mm Art lenses made for mirrorless cameras) have yet to appear in Canon RF mount versions. Will they ever? In moves that evoked much disdain, Samyang and Viltrox were both ordered by Canon to cease production of their RF auto-focus lenses.
For their mirrorless R cameras, Canon has not authorized any third-party lens makers, forcing you to buy costly Canon L glass, or settle for their lower-grade STM lenses, or opt for reverse-engineered manual-focus lenses from makers such as TTArtisan and Laowa/Venus Optics. While they are good, they are not up to the optical standards of Canon’s L-series glass.
I know, as I own several RF-mount TTArtisan wide-angle lenses and the Laowa 15mm f/2 lens. You can find my tests of those lenses at AstroGearToday.com. Look under Reviews: Astrophotography Gear.
The trio of RF lenses tested here work on all Canon EOS R-series cameras, including their R7 and R10 cropped-frame cameras. However, they will not work on any Canon DSLRs.
Two of the lenses, the RF15-35mm F/2.8 and RF70-200mm F/4, are designs updated from older Canon DSLR lenses with similar specs. The RF28-70mm F/2 does not have an equivalent focal length range and speed in Canon’s DSLR lens line-up. Indeed, nobody else makes a lens this fast covering the “normal” zoom range.
Together, the three lenses cover focal lengths from 15mm to 200mm, with some overlap. A trio of zooms like this — a wide-angle, normal, and telephoto — is often called a “holy trinity” set, a popular combination all camera manufacturers offer to cover the majority of applications.
However, my interest was strictly for astrophotography, with stars the test subjects.
NOTE: CLICK or TAP on a test image to download a full-resolution image for closer inspection. The images, while low-compression JPGs, are large and numerous, and so will take time to fully load and display. Patience!
I tested the trio of lenses on same-night exposures of a starry but moonlit sky, using the 45-megapixel Canon R5 camera mounted on a motorized star tracker to follow the rotating sky. With one exception noted, any distortion of stars from perfect pinpoints is due to lens aberrations, not star trailing. The brighter moonlit sky helped reveal non-uniform illumination from lens vignetting.
I shot each lens wide-open at its maximum aperture, as well as one stop down from maximum, to see how aberrations and vignetting improved.
I did not test auto-focus performance, nor image stabilization (only the RF28-70mm lacks internal IS), nor other lens traits unimportant for astro work such as bokeh or close focus image quality.
I also compared the RF15-35mm on same-night dark-sky tests against a trio of prime lenses long in my stable: the Rokinon 14mm SP, and Canon’s older L-series 24mm and 35mm primes, all made for DSLRs.
Each of the Canon “holy trinity” of zoom performs superbly, though not without some residual lens aberrations such as corner astigmatism and, in the RF28-70mm, slight chromatic aberration at f/2.
However, what flaws they show are well below the level of many older prime lenses made for DSLR cameras.
The RF lenses’ major optical flaw is vignetting, which can be quite severe at some focal lengths, such as in the RF70-200mm at 200mm. But this flaw can be corrected in processing.
These are lenses that can replace fixed-focal length primes, though at considerable cost, in part justifiable in that they negate the need for a suite of many prime lenses.
The performance of these and other new lenses made for mirrorless cameras from all brands is one good reason to switch from DSLR to mirrorless cameras.
Lens Specs and Applications
Canon RF15-35mm F/2.8 L IS USM
The Canon RF15-35mm F/2.8 L is made primarily for urban photography and landscapes by day. My main application is using it to take landscapes by night, and auroras, where its relatively fast f/2.8 speed helps keeps exposure times short and ISO speeds reasonably low. However, the RF15-35mm can certainly be used for tracked wide-angle Milky Way and constellation portraits.
The lens weighs a moderate 885 grams (31 ounces or 1.9 pounds) with lens hood and end caps, and accepts 82mm filters, larger than the 72mm or 77mm filter threads of most astrophoto-friendly lenses. Square 100mm filters will work well on the lens, even at the 15mm focal length. There are choices, such as from KASE, for light pollution reduction and star diffusion filters in this size and format. I have reviews of these filters at AstroGearToday.com, both here for light pollution filters and here for starglow filters.
Canon offers a lower-cost alternative in this range, their RF14-35mm. But it is f/4, a little slow for nightscape, aurora, and Milky Way photography. I have not tested one.
Canon RF28-70mm F/2 L USM
The big Canon RF28-70mm F/2 is aimed at wedding and portrait photographers, though the lens is suitable for landscape work. While I do use it for nightscapes, my primary use is for tracked Milky Way and constellation images, where its range of fields of view nicely frames most constellations, from big to small.
I justified its high cost by deciding it replaces (more or less!) prime lenses in the common 24mm, 35mm, 50mm, and 85mm focal lengths. Its f/2 speed does bring it into fast prime lens territory. It’s handy to have just one lens to cover the range.
Canon offers a lower-cost alternative here, too, their RF24-70mm. But it is f/2.8. While this is certainly excellent speed, I like having the option of shooting at f/2. An example is when using narrowband nebula filters such as red hydrogen-alpha filters, where shooting at f/2 keeps exposures shorter and/or ISOs lower when using such dense filters. I use this lens with an Astronomik 12-nanometre H-α clip-in filter. An example is in one of the galleries below.
While a clip-in filter shifts the infinity focus point inward (to as close as the 2-metre mark with the RF28-70mm at 28mm, and to 6 metres at 70mm), I did not find that shift adversely affected the lens’s optical performance. That’s not true of all lenses.
Make no mistake, the RF28-70mm is one hefty lens, weighing 1530 grams (54 ounces or 3.4 pounds). Its front-heavy mass demands a solid tripod head. Its large front lens accepts big 95mm filters, a rare size with few options available. I found one broadband light pollution filter in this size, from URTH. Otherwise, you need to use in-body clip-in filters. Astronomik makes a selection for Canon EOS R cameras.
Canon RF70-200mm F/4 L IS USM
The Canon RF70-200mm F/4 is another portrait or landscape lens. I use it primarily for bright twilight planet conjunctions and moonrise scenes, where its slower f/4 speed is not a detriment. However, as my tests show, it can be used for tracked deep-sky images, where it is still faster than most short focal length telescopes.
The RF70-200mm lens weighs 810 grams (28 ounces, or 1.75 pounds) with lens hood and caps, so is light for a 70-to-200mm zoom. It is also compact. At just 140mm long when set to 70mm, it is actually the shortest lens of the trio. However, the barrel extends to 195mm long when zoomed out to 200mm focal length.
Canon offers the more costly and, at 1200 grams, heavier RF70-200mm F/2.8 lens which might be a better choice for deep-sky imaging where the extra stop of speed can be useful. But in this case, I chose the slower, more affordable – though still not cheap – f/4 version. It accepts common 77mm filters, as does the f/2.8 version.
Canon RF15-35mm F/2.8 L IS USM
Like the other two zoom lenses tested, the RF15-35mm is very sharp on axis. Even wide open, there’s no evidence of softness and star bloat from spherical aberration, the bane of cheaper lenses.
Coloured haloes from longitudinal chromatic aberration are absent, except at 28mm and 35mm (shown here) when wide open at f/2.8, where bright stars show a little bit of blue haloing. At f/4, this minor level of aberration disappears.
Canon RF28-70mm F/2 L USM
The big RF28-70mm is also very sharp on-axis but is prone to more chromatic aberration at f/2, showing slight magenta haloes on bright stars at the shorter focal lengths and pale cyan haloes at 70mm in my test shots. Such false colour haloes can be very sensitive to precise focus, though with refractive optics the point of least colour is often not the point of sharpest focus.
At f/2, stars are a little softer at 70mm than at 28mm. Stopping down to f/2.8 eliminates this slight softness and most of the longitudinal chromatic aberration.
Canon RF70-200mm F/4 L IS USM
Unlike prime telephotos I’ve used, the RF70-200mm shows negligible chromatic aberration on-axis at all focal lengths, even at f/4. Stars are a little softer at the longest focal length at f/4, perhaps from slight spherical aberration, though my 200mm test shots are also affected by a little mistracking, trailing the stars slightly.
Stopping down to f/5.6 sharpens stars just that much more at 200mm.
The corners are where we typically separate great lenses from the merely good. And it is where zoom lenses have traditionally performed badly. For example, my original Canon EF16-35mm f/2.8 lens was so bad off-axis I found it mostly unusable for astro work. Not so the new RF15-35mm, which is the RF replacement for Canon’s older EF16-35mm.
To be clear – in these test shots you might think the level of aberrations are surprising for premium lenses. But keep in mind, to show them at all I am having to pixel-peep by enlarging all the test images by 400 percent, cropping down to just the extreme corners.
Check the examples in the Compared to DSLR Lenses section and in the Finished ImagesGalleries for another look at lens performance in broader context.
Canon RF15-35mm F/2.8 L IS USM
Surprisingly, this RF’s best performance off-axis is actually at its shortest focal length. At 15mm it exhibits only some slight tangential astigmatism, elongating stars away from the frame centre. At 24mm aberrations appear slightly worse than at the other focal lengths, showing some flaring from sagittal astigmatism and perhaps coma as well, aberrations seen to a lesser degree at 28mm and 35mm, making stars look like little three-pointed triangles.
The aberrations reduce when stopped down to f/4, but are still present, especially at 24mm, this lens’s weakest focal length, though only just.
While the RF15-35mm isn’t perfect, it outperforms other prime lenses I have, and that I suspect most users will own or have used in the past with DSLRs. Only new wide-angle premium primes for the RF mount, if and when we see them, will provide better performance.
Canon RF28-70mm F/2 L USM
The RF28-70mm’s fast f/2 speed, unusual for any zoom lens, was surely a challenge to design for. Off-axis when wide open at f/2 it does show astigmatism at the extreme corners at all focal lengths, but the least at 50mm, and the worst at 28mm where a little lateral chromatic aberration is also visible, adding slight colour fringing.
Sharpness off-axis improves markedly when stopped down one stop to f/2.8, where at 50mm stars are now nearly perfect to the corners. Indeed, performance is so good at 50mm, I think there would be little need to buy the Canon RF50mm prime, unless its f/1.2 speed is deemed essential.
With the RF28-70mm at f/2.8, stars still show some residual astigmatism at 28mm and 35mm, but only at the extreme corners.
Canon RF70-200mm F/4 L IS USM
The RF70-200mm telephoto zoom shows some astigmatism and coma at the corners when wide open at f/4, with it worse at the shorter focal lengths. While lens corrections have been applied here, the 200mm image still shows a darker corner from the vignetting described below.
Stopping down to f/5.6 eliminates most of the off-axis aberrations at 135mm and 200mm focal lengths but some remain at 70mm and to a lesser degree at 100mm.
This is a lens that can be used at f/4 even for the demands of deep-sky imaging, though perfectionists will want to stop it down. At f/5.6 it is similar in speed to many astrographic refractors, though most of those start at about 250mm focal length.
In the previous test images, I applied lens corrections (but no other adjustments) to each of the raw files in Adobe Camera Raw, using the settings ACR automatically selects from its lens database. These corrections brightened the corners.
In this next set I show the lenses’ weakest point, their high level of vignetting. This light falloff darkens the corners by a surprising amount. In the new generation of lenses for mirrorless cameras, it seems lens designers are choosing to sacrifice uniform frame illumination in order to maximize aberration corrections. The latter can’t be corrected entirely, if at all, by software.
However, corrections applied either in-camera or at the computer can brighten corners, “flattening” the field. I show that improvement in the section that follows this one.
Canon RF15-35mm F/2.8 L IS USM
In the wide-angle zoom, vignetting darkens just the corners at 15mm, but widens to affect progressively more of the frame at the longer focal lengths. The examples show the entire right side of the frame. I show the effect just at f/2.8.
Though I don’t show examples with the two wider zooms, with all lenses vignetting decreases dramatically when each lens is stopped down by even one stop. The fields become much more evenly illuminated, though some darkening at the very corners remains one stop down.
Canon RF28-70mm F/2 L USM
In this “normal” zoom, vignetting performance is similar at all focal lengths, though it affects a bit more of the field at 70mm than at 28mm. Again, while I’m not presenting an example, vignetting decreases a lot when this lens is stopped down to f/2.8. While the extra stop of speed is certainly nice to have at times, I usually shoot the RF28-70mm at f/2.8.
Canon RF70-200mm F/4 L IS USM
In this telephoto zoom, vignetting is fairly mild at the shorter focal lengths but becomes severe at 200mm, affecting much of the field. It is far worse than I see with my older Canon EF200mm f/2.8 prime, a lens that is not as sharp at f/4 as the RF zoom.
The faster RF70-200mm f/2.8 lens, which I had the chance to test one night last year, showed as much, if not more, vignetting than the f/4 version. See my test here at AstroGearToday.com. I thought the f/4 version would be better for vignetting, but it is not.
In this case, as the vignetting is so prominent at 200mm, I show above how much it improves when stopped down to f/5.6, in a comparison with the lens at f/4, both with no lens corrections applied in processing. The major improvement comes from the smaller aperture alone. For twilight scenes, I’d suggest stopping this lens down to better ensure a uniform sky background.
In this next set I show how well applying lens corrections improves the vignetting at the focal lengths where each of the lenses is at its worse, and with each at its widest aperture.
I show this with Adobe Camera Raw but Lightroom would provide identical results. I did not test lens corrections with other programs such as CaptureOne, DxO PhotoLab, or ON1 Photo Raw, which all have automatic lens corrections as well.
Canon RF15-35mm F/2.8 L IS USM
Applying lens corrections in Adobe Camera Raw certainly brightened the corners and edges, though still left some darkening at the very corners that can be corrected by hand in the Manual tab.
Canon RF28-70mm F/2 L USM
ACR’s lens corrections helped but did not completely eliminate the vignetting here. Corner darkening remained. Manually increasing the vignetting slider can provide that extra level of correction needed.
Canon RF70-200mm F/4 L IS USM
The high level of vignetting with this lens at 200mm largely disappeared with lens corrections, though not entirely. For deep-sky imaging, users might prefer to shoot and apply flat-field frames. I prefer to apply automatic and manual corrections to the raw files, to stay within a raw workflow as much as possible.
Same Focal Length Comparisons
With the trio of lenses offering some of the same focal lengths, here I show how they compare at three of those shared focal lengths. I zoom into the upper right corners here, as with the Corner Aberrations comparisons above.
RF15-35mm vs. RF28-70mm at 28mm
With both lenses at 28mm and at the same f/2.8 aperture (though the RF28-70mm is now stopped down one stop), it’s a toss up. Both show corner aberrations, though of a different mix, distorting stars a little differently. The RF28-70mm shows some lateral chromatic aberration, but the RF15-35mm shows a bit more flaring from astigmatism.
RF15-35mm vs. RF28-70mm at 35mm
The story is similar with each lens at 35mm. Stars seem a bit sharper in the RF15-35mm though are elongated more by astigmatism at the very corners. Lens corrections have been applied here and with the other two-lens comparison pairs.
RF28-70mm vs. RF70-200mm at 70mm
Here I show the RF28-70mm at f/2.8 and the RF70-200mm wide open at f/4, with both set to 70mm focal length. The telephoto lens shows a little more softening and star bloating from corner aberrations, though both perform well.
Compared to DSLR Lenses
Here I try to demonstrate just how much better at least one of the zooms on test here is compared to older prime lenses made for DSLRs. The Canon lenses are labeled EF, for Canon’s EF lens mount used for decades on their DSLRs and EOS film cameras. Both are premium L lenses.
I shot this set on a different night than the previous examples, with some light cloud present which added various amounts of glows around stars. But the test shots still show corner sharpness and aberrations well, in this case of the upper left corners of all frames.
Canon RF15-35mm at 35mm vs. Canon EF35mm L
The Canon EF35mm is the original Mark I version, which Canon replaced a few years ago with an improved Mark II model. So I’m sure if you were to buy an EF35mm lens now (or if that’s the model you own) it will perform better than what I show here.
Both lenses are at f/2.8, wide open for the RF lens, but stopped down two stops for the f/1.4 EF lens.
The zoom lens is much sharper to the corners, with far less astigmatism and none of the lateral chromatic aberration and field curvature (softening stars at the very corner) of the old EF35mm prime. I thought the EF35mm was a superb lens, and used it a lot over the last 15 years for Milky Way panoramas. I would not use it now!
Canon RF15-35mm at 24mm vs. Canon EF24mm L
Bought in the early years of DSLRs, the EF24mm tested here is also an original Mark I model, since replaced by an improved Mark II 24mm. The old 24mm is good, but shows more astigmatism than the RF lens, and some field curvature and purple chromatic aberration not present at all in the RF lens.
And this is comparing it to the RF lens at its weakest focal length, 24mm. It still handily outperforms the old EF24mm prime.
Canon RF15-35mm at 15mm vs. Rokinon 14mm SP
Canon once made an EF14mm f/2.8 L prime, but I’ve never used it. For a lens in this focal length, one popular with nightscape photographers, I’ve used the ubiquitous Rokinon/Samyang 14mm f/2.8 manual lens. While a bargain at about $300, I always found it soft and aberrated at the corners. See my test of 14mm ultra-wides here.
A few years ago I upgraded to the Rokinon 14mm f/2.4 lens in their premium SP series (about $800 for the EF-mount version). While a manual lens, it does have electrical contacts to communicate lens metadata to the camera. Like all EF-mount lenses from any brand, it can be adapted to Canon R cameras using Canon’s $100 EF-EOS R lens adapter.
The Rokinon SP is the only prime I found that beat the RF zoom. It provided sharper images to the corners than the RF15-35mm at 15mm. The Rokinon also offers the slightly faster maximum aperture of f/2.4 (which Canon cameras register as f/2.5). Vignetting is severe, but like the RF lenses can be corrected – Camera Raw has this lens in its database. What is not so easy to correct is some slight colour shift at the corners.
Another disadvantage, as with many other 14mm lenses, is that the SP lens cannot accept front-mounted filters. The RF15-35mm can.
Nevertheless, until Canon comes out with a 12mm to 14mm RF prime, or allows Sigma to, an adapted Rokinon 14mm SP is a good affordable alternative to the RF15-35mm.
All the RF lens bodies are built of weight-saving engineered plastic incorporating thorough weather sealing. There is nothing cheap about their fit, finish or handling. Each lens has textured grip rings for the zoom, focus and a control ring that can be programmed to adjust either aperture, ISO, exposure compensation or other settings of your choosing.
As with all modern auto-focus lenses, the manual focus ring on each lens does not mechanically move glass. It controls a motor that in turn focuses the lens, so-called “focus-by-wire.” However, I found that focus could be dialled in accurately. But if the camera is turned off, then on again, the lens will not return to its previous focus position. You have to refocus to infinity each time the camera is powered up, a nuisance.
Unlike some Nikon, Sony, Samyang, and Sigma lenses, none of the Canon lenses have a focus lock button, or any way of presetting an infinity focus point, or simply having the lens remember where it was last set. I would hope Canon could address that deficiency in a firmware update.
With all the zooms, I did not find any issue with “zoom creep.” The telescoping barrels remained in place during long exposures and did not slowly retract when aimed up. While the RF28-70mm and RF70-200mm each have a zoom lock switch, it locks the lens only at its shortest focal length.
Each lens is parfocal within its zoom range. Focus at one zoom position, and it will be in focus for all the focal lengths. I usually focus at the longest focal length where it is easiest to judge focus by eye, then zoom out to frame the scene.
FINISHED IMAGES GALLERIES
Here I present a selection of final, processed images (four for each lens), so you can better see how each performs on real-world celestial subjects. To speed download, the images are downsized to 2048 pixels wide.
As per my comments at top, the RF15-35mm is my primary nightscape lens, the RF28-70mm my lens for wide-field constellation and Milky Way shots, while the RF70-200mm is for conjunctions and Moon scenes. It would also be good for eclipses.
Image Gallery withCanon RF15-35mm F/2.8 L IS USM
Image Gallery withCanon RF28-70mm F/2 L USM
Image Gallery withCanon RF70-200mm F/4 L IS USM
CONCLUSIONs and recommendations
If you are a Canon user switching from your aging but faithful DSLR to one of their mirrorless R cameras, each of these lenses will perform superbly for astrophotography. At a price! Each is costly. But the cost of older EF lenses has also increased in recent months.
The other native RF L-series lenses in this focal length range, Canon’s RF50mm and RF85mm f/1.2 primes, are stunning … but also expensive. As I’m sure any coming RF wide-angle L primes will be, if and when they ever appear!
The cheaper alternative – not the least because you might already own them! – is using adapted EF-mount lenses made for DSLRs, either from Canon or other brands. But in many cases, as I’ve shown, the new RF glass is sharper, especially when on a high-resolution camera such as the Canon R5 I used for all the testing.
And there’s the harsh reality that Canon is discontinuing many EF lenses. You can now buy some only used. For example, the EF135mm f/2 L and EF200mm f/2.8 L are both gone.
Until Canon licenses other companies to issue approved lenses for their RF mount – if that happens at all – our choices for native RF lenses are limited. However, the quality of Canon’s L lenses is superb. I now use these zooms almost exclusively, and financed most of their considerable cost by selling off a ream of older cameras and lenses.
If there’s one lens to buy for most astrophotography, it might be the big RF28-70mm F/2, a zoom lens that comes close to offering it all: flexibility, optical quality and speed. The RF24-70mm F/2.8 is a more affordable choice, though I have not tested one.
If nightscapes are the priority, the RF15-35mm F/2.8 would see a lot of use, as perhaps the only lens you’d need.
Of the trio, the RF70-200mm was the lowest priority on my wish list. But it has proven to be very useful for framing horizon scenes.
The superb optics of these and other new lenses made for mirrorless cameras is one good reason to upgrade from a DSLR to a mirrorless camera, in whatever brand you prefer.
On August 7, 2022 we were treated to a fine aurora and a superb showing of the anomalous STEVE arc across the sky.
Where I live in southern Alberta we are well positioned to see a variety of so-called “sub-auroral” phenomena — effects in the upper atmosphere associated with auroras but that appear south of the main auroral arc, thus the term “sub-auroral.”
The main auroral band typically lies over Northern Canada, at latitudes 58° to 66°, though it can move south when auroral activity increases. However, on August 7, the Kp Index was predicted to reach Kp5, on the Kp 0 to 9 scale, so moderately active, but not so active it would bring the aurora right over me at latitude 51° N, and certainly not down over the northern U.S., which normally requires Kp6 or higher levels.
So with Kp5, the aurora always appeared in my sky this night to the north, though certainly in a fine display, as I show above.
However, at Kp5, the amount of energy being pumped into the magnetosphere and atmosphere around Earth is high enough to trigger (through mechanisms only beginning to be understood) some of the unique phenomena that occur south of the main aurora. These often appear right over me. That was the case on August 7.
I captured the above panoramas of the aurora early in the night, when we also were treated to a late season display of noctilucent clouds low in the north. These are high altitude water-vapour clouds up almost as high as the aurora. They are common in June and July from here (we are also in an ideal latitude for seeing them). But early August was the latest I had ever sighted NLCs.
As the NLCs faded, the auroral arc brightened, promising a good show, in line with the predictions (which don’t always come true!). The main aurora reached a peak in activity about 11:30 pm MDT, when it was bright and moving along the northern and northeastern horizon. It then subsided in brightness and structure, giving the impression the show was over.
But that’s exactly when STEVE can — and this night did! — appear.
Sure enough, about 12:15 am, a faint arc appeared in the east, which slowly extended to cross the sky, passing straight overhead. This was STEVE, short for Strong Thermal Emission Velocity Enhancement.
STEVE is not an aurora per se, which is caused by electrons raining down from the magnetosphere. STEVE is a ribbon of hot (~3000°) gas flowing east to west. STEVE typically appears for no more than an hour, often less, before he fades from view.
At his peak, STEVE is often accompanied by green “picket-fence” fingers hanging down from the main pink band, which also have a westward rippling motion. These do seem to be caused by vertically moving electrons.
This night I shot with three cameras, with lenses from 21mm to 7.5mm, including two fish-eye lenses needed to capture the full extent of sky-spanning STEVE. I shot still, time-lapses, and real-time videos, compiled below.
Amateur photos like mine have been used to determine the height of STEVE, which seems to be 250 to 300 km, higher than the main components of a normal aurora. Indeed, previous images of mine have formed parts of the data sets for two research papers, with me credited as a citizen scientist co-author.
STEVE is a unique example of citizen scientists working with the professional researchers to solve a mystery that anyone who looks up at the right time and from the right place can see. August 7-8, 2022 and my backyard in Alberta was such a time and place.
As a bonus, a few frames recorded Perseid meteors, with the annual shower becoming active.
For a video compilation of some of my stills and videos from the night, see this Vimeo video.
In a format similar to my other popular camera tests, I put the 45-megapixel Canon R5 mirrorless camera through its paces for the demands of astrophotography.
In a sequel to my popular post from September 2021 where I reviewed the Canon R6 mirrorless camera, here is a similar test of its higher-megapixel companion, the Canon R5. Where the R6 has a modest 20-megapixel sensor with relatively large 6.6-micron pixels, the R5 is (at present) Canon’s highest megapixel camera, with 45 megapixels. Each pixel is only 4.4 microns across, providing higher resolution but risking more noise.
Is the higher noise noticeable? If so, does that make the R5 less than ideal for astrophotography? To find out, I tested an R5 purchased locally in Calgary from The Camera Store in May 2022.
NOTE: CLICK orTAP on any image to bring it up full screen for closer inspection. The blog contains a lot of high-res images, so they may take a while to all load. Patience! Thanks!
The Canon R5 proved to be surprisingly low in noise, and has worked very well for nightscape, lunar and deep-sky photography (as shown below), where its high resolution does produce a noticeable improvement to image detail, with minimal penalty from higher noise. Its 8K video capability has a place in shooting the Moon, Sun and solar eclipses. It was not so well suited to shooting videos of auroras.
The Canon R5 is superb for its:
High resolution with relatively low noise
ISO invariant sensor performance for good shadow recovery
Good live view display with ISO boost in Movie mode
8K video has its attraction for eclipse photography
Good top LCD information screen missing in the R6
No magenta edge “amp glow” that the R6 shows
Higher 6x and 15x magnifications for precise manual focusing
Good battery life
Pro-grade Type N3 remote port
The Canon R5 is not so superb for its:
Noise in stills and movies is higher than in the R6
Propensity for thermal-noise hot pixels in shadows
Not so suitable for low-light video as the R6
Overheating in 8K video
Live View image is not as bright as in the R6’s Movie mode
CHOOSING THE R5
Since late 2019 my main camera for all astrophotography has been the Canon Ra, a limited-edition version of the original R, Canon’s first full-frame mirrorless camera that started the R series. The Ra had a special infra-red cutoff filter in front of the sensor that passed a higher level of visible deep-red light, making it more suitable for deep-sky astrophotography than a standard DSLR or DSLM (mirrorless) camera. The Ra was discontinued after two years on the market, a lifetime similar to Canon’s previous astronomical “a” models, the 20Da and 60Da.
I purchased the Canon R6 in late 2021, primarily to use it as a low-light video camera for aurora photography, replacing the Sony a7III I had used for several years and reviewed here. Over the last year, I sold all my non-Canon cameras, as well as the Canon 6D MkII DSLR (reviewed here), to consolidate my camera gear to just Canon mirrorless cameras and lenses.
The R6 has proven to be an able successor to the Sony for me, with the R6’s modest megapixel count and larger pixels making it excellent for low-light video. But the higher resolution of the R5 was still attractive. So I have now added it to my Canon stable. Since doing so, I have put it through several of my standard tests to see how suitable it is for the demands of astrophotography, both stills and video.
Here are my extensive results, broken down by various performance criteria. I hope you will find my review useful in helping you make a purchase decision.
LIVE VIEW FRAMING
First, why go mirrorless at all? For astrophotography, the big difference compared to even a high-end DSLR, is how much brighter the “Live View” image is when shooting at night. DSLM cameras are always in Live View – even the eye-level viewfinder presents a digital image supplied by the sensor.
And that image is brighter, often revealing more than what a DSLR’s optical viewfinder can show, a great advantage for framing nightscape scenes, and deep-sky fields at the telescope.
The R5 certainly presents a good live view image. However, it is not as bright nor as detailed as what the R6 can provide when placed in its Movie mode and with the ISO bumped up to the R6’s highest level of ISO 204,800, where the Milky Way shows up, live!
The R5 only goes as high as ISO 51,200, and so as I expected it does not provide as bright or detailed a preview at night as the R6 can. However, the R5 is better than the original R for live-view framing, and better than any Canon DSLR I’ve used.
LIVE VIEW FOCUSING
Like the R6, the R5 can autofocus accurately on bright stars and planets. By comparison, while the Ra can autofocus on distant bright lights, it fails on bright stars or planets.
Turning on Focus Peaking makes stars turn red, yellow or blue (your choice of colours) when they are in focus, as a reassuring confirmation.
In manual focus, an additional Focus Aid overlay, also found in the R6, provides arrows that close up and turn green when in focus on a bright star or planet.
Or, as shown above, you can zoom in by 6x or 15x to focus by eye the old way by examining the star image. These are magnification levels higher than the 5x and 10x of the R6 and most other Canon cameras, and are a great aid to precise focusing, necessary to make full use of the R5’s high resolution, and the sharpness of Canon’s RF lenses. The 15x still falls short of the Ra’s 30x for ultra-precise focusing on stars, but it’s a welcome improvement nonetheless.
In all, while the R5 is not as good as the R6 for framing in low light, it is better for precise manual focusing using its higher 15x magnification.
NOISE PERFORMANCE — NIGHTSCAPES
The key camera characteristic for astrophoto use is noise. There is no point in having lots of resolution if, at the high ISOs we use for most astrophotography, the detail is lost in noise. But I was pleasantly surprised that proved not to be the case with the R5.
As I show below, noise is well controlled, making the R5 usable for nightscapes at ISOs up to 3200, if not 6400 when needed in a pinch.
With 45 megapixels, at the upper end of what cameras offer today, the R5 has individual pixels, or more correctly “photosites,” that are each 4.4 microns in size, the “pixel pitch.”
This is still larger than the 3.7-micron pixels in a typical 24-megapixel cropped-frame camera like the Canon R10, or the 3.2-micron pixels found in a 32-megapixel cropped-frame camera like the Canon R7. Both are likely to be noisier than the R5, though will provide even higher resolution, as well as greater magnification with any given lens or telescope.
By comparison, the 30-megapixel full-frame R (and Ra) has a pixel pitch of 5.4 microns, while the 20-megapixel R6’s pixel pitch is a generous 6.6 microns. Only the 12-megapixel Sony a7SIII has larger 8.5-micron pixels, making it the low-light video champ.
The bigger the photosites (i.e. the larger the pixel pitch), the more photons each photosite can collect in a given amount of time – and the more photons they can collect, period, before they overfill and clip highlights. More photons equals more signal, and therefore a better signal-to-noise ratio, while the greater “full-well depth” yields higher dynamic range.
However, each generation of camera improves the signal-to-noise ratio by suppressing noise via its sensor design and improved signal processing hardware and firmware. The R5 and R6 each use Canon’s latest DIGIC X processor.
In nightscapes the R5 did show more noise at high ISOs, especially at ISO 6400, than the R6 and Ra, but the difference was not large, perhaps one stop at most, if that. What was noticeable was the presence in the R5 of more hot pixels from thermal noise, as described later.
At slower ISOs the R5 showed a similar level of noise as the R6 and Ra, but a finer-grained noise than the R6, in keeping with the R5’s smaller pixels. In this test set, the R5 did not exhibit noticeably more noise than the other two cameras. This was surprising.
NOTE: In these comparisons I have not resampled the R5 images down to the megapixel count of the R6 to equalize them, as that’s not what you would do if you bought an R5. Instead, I have magnified the R6 and Ra’s smaller images so we examine the same area of each camera’s images.
As with the R6, I also saw no “magic ISO” setting where the R5 performed better than at other settings. Noise increased in proportion to the ISO speed. The R5 proved perfectly usable up to ISO 3200, with ISO 6400 acceptable for stills when necessary. But I would not recommend the R5 for those who like to shoot Milky Way scenes at ISO 12,800.
For nightscapes, a good practice that would allow using lower ISO speeds would be to shoot the sky images with a star tracker, then take separate long untracked exposures for the ground.
NOTE: In my testing I look first and foremost at actual real-world results. For those interested in more technical tests and charts, I refer you to DxOMark’s report on the Canon R5.
NOISE PERFORMANCE — DEEP-SKY
Deep-sky imaging with a tracking mount is more demanding, due to its longer exposures of up to several minutes for each “sub-frame.”
On a series of deep-sky exposures through a telescope, above, the R5 again showed quite usable images up to ISO 1600 and 3200, with ISO 6400 a little too noisy in my opinion unless a lot of noise reduction was applied or many images were shot to stack later.
As with the nightscape set, at high ISOs, such as at ISO 6400, the R5 did show more noise than the R6 and Ra, as well as more colour splotchiness in the dark sky, and lower contrast. The lower dynamic range of the R5’s smaller pixels is evident here.
Just as with nightscapes, the lesson with the R5 is to keep the ISO low if at all possible. That means longer exposures with good auto-guiding, but that’s a best practice with any camera.
At lower ISOs that provide better dynamic range, shown above, the difference in noise levels between the three cameras was not that obvious. Each camera presented very similar images, with the R6 having a coarser noise than the Ra and R5.
In all, I was surprised the R5 performed as well as it did for deep-sky imaging. See my comments below about its resolution advantage.
The flaw in many Canon DSLRs, one documented in my 2017 review of the 6D Mark II, was their poor dynamic range due to the lack of an ISO invariant sensor design.
Canon R-series mirrorless cameras have largely addressed this weakness. As with the R and R6, the sensor in the R5 appears to be nicely ISO invariant.
Where ISO invariancy shows itself to advantage is on nightscapes where the starlit foreground is often dark and underexposed. Bringing out detail in the shadows in raw files requires a lot of Shadow Recovery or increasing the Exposure slider. Images from an ISO invariant sensor can withstand the brightening “in post” far better, with minimal noise increase or degradations such as a loss of contrast, added banding, or horrible discolourations.
As I do for such tests, I shot sets of images at the same shutter speed, one well-exposed at a high ISO, then several at successively lower ISOs to underexpose by 1 to 4 stops. I then brightened the underexposed images by increasing the Exposure in Camera Raw by the same 1 to 4 stops. In an ideal ISO invariant sensor, all the images should look the same.
The R5 performed well in images underexposed by up to 3 stops. Images underexposed by 4 stops started to fall apart with low contrast and a magenta cast. This was worse performance than the R6, which better withstood underexposure by as much as 4 stops, and fell apart at 5 stops of underexposure.
While it can withstand underexposure, the lesson with the R5 is to still expose nightscapes as well as possible, likely requiring a separate longer exposure for the dark ground. Expose to the right! Don’t depend on being able to save the image by brightening “in post.” But again, that’s a best practice with any camera.
Here I repeat some of the background information from my R6 review. But it bears repeating, as even skilled professional photographers often misunderstand the various forms of noise and how to mitigate them.
All cameras will exhibit thermal noise in long exposures, especially on warm nights. This form of heat-induced noise peppers the shadows with bright or “hot” pixels, often brightly coloured.
This is not the same as the shot and read noise that adds graininess to high-ISO images and that noise reduction software can smooth out later in post.
I found the R5 was prone to many hot pixels in long nightscape exposures where they show up in dark, underexposed shadows. I did not find a prevalence of hot pixels in well-exposed deep-sky images.
LONG EXPOSURE NOISE REDUCTION
With all cameras a setting called Long Exposure Noise Reduction (LENR) eliminates this thermal noise by taking a “dark frame” and subtracting it in-camera to yield a raw file largely free of hot pixels, and other artifacts such as edge glows.
The LENR option on the R5 did eliminate most hot pixels, though sometimes still left, or added, a few (or they might be cosmic ray hits). LENR is needed more on warm nights, and with longer exposures at higher ISOs. So the extent of thermal noise in any camera can vary a lot from shoot to shoot, and season to season.
The comparison above shows just thermal noise in long exposures with and without LENR, to show its effectiveness. However, bear in mind in this demo the raw files have been boosted a lot in exposure and contrast (using DxO PhotoLab with the settings shown) to exaggerate the visibility of the noise.
Like the R6, when LENR is actively taking a dark frame, the R5’s rear screen indicates “Busy,” which is annoyingly bright at night, exactly when you would be employing LENR. To hide this display, the only option is to close the screen. Instead, the unobtrusive top LCD screen alone should be used to indicate a dark frame is in progress. It does with the Ra, though Busy also displays on its rear screen as well, which is unnecessary.
As with all mirrorless cameras, the R5 lacks the “dark frame buffer” present in Canon full frame DSLRs that allows several exposures to be taken in quick succession even with LENR on.
With all Canon R cameras, turning on LENR forces the camera to take a dark frame after every light frame, doubling the time it takes to finish every exposure. That’s a price many photographers aren’t willing to pay, but on warm nights I find it can be essential, and a best practice, for the reward of cleaner images out of camera. I found it is certainly a good practice with the R5.
TIP: If you find hot pixels are becoming more obvious over time, try this trick: turn on the Clean Manually routine for 30 seconds to a minute. In some cameras this can remap the hot pixels so the camera can better eliminate them.
Using LENR with the R5 did not introduce any oddities such as oddly-coloured, green or wiped-out stars. Even without LENR I saw no evidence of green stars, a flaw that plagues some Sony cameras at all times, or Nikons when using LENR.
Canons have always been known for their good star colours, and the R5 maintains the tradition. According to DPReview the R5 has a mild low-pass anti-alias filter in front of its sensor. Cameras which lack such a sensor filter do produce sharper images, but stars that occupy only one or two pixels might not de-Bayer properly into the correct colours. I did not find that an issue with the R5.
As in the R6, I also saw no evidence of “star-eating,” a flaw Nikons and Sonys have been accused of over the years, due to aggressive in-camera noise reduction even on raw files. Canons have largely escaped charges of star-eating.
The R5 I bought was a stock “off-the-shelf” model. It is Canon’s now-discontinued EOS Ra that was “filter-modified” to record a greater level of the deep-red wavelength from red nebulas in the Milky Way. As I show below, compared to the Ra, the R5 did well, but could not record the depth of nebulosity the Ra can, to be expected for a stock camera.
However, bright nebulas will still be good targets for the R5. But if it’s faint nebulosity you are after, both in wide-field Milky Way images and telescopic close-ups, consider getting an R5 “spectrum modified” by a third-party supplier. Or modifying an EOS R.
EDGE ARTIFACTS and EDGE GLOWS
DSLRs are prone to vignetting along the top and bottom of the frame from shadowing by the upraised mirror and mirror box. Not having a mirror, and a sensor not deeply recessed in the body, largely eliminates this edge vignetting in mirrorless cameras.
While the Ra shows a very slight vignetting along the bottom of the frame (visible in the example above), the R5 was clean and fully illuminated to the edges, as it should be.
I was also pleased to see the R5 did not exhibit any annoying “amp glows” — dim, often magenta glows at the edge of the frame in long exposures, created by heat emitted from sensor electronics adding infrared (IR) glows to the image.
I saw noticeable amp glows in the Canon R6 which could only be eliminated by taking LENR dark frames. It’s a flaw that has yet to be eliminated with firmware updates. Taking LENR darks is not required with the R5, except to reduce thermal hot pixels as noted above.
With a lack of IR amp glows, the R5 should work well when filter-modified to record either more visible Hydrogen-alpha red light, or deeper into the infrared spectrum.
Resolution — Nightscapes
Now we come to the very reason to get an R5, its high resolution. Is the difference visible in typical astrophotos? In a word, yes. If you look closely.
If people only see your photos on Facebook or Instagram, no one will ever see any improvement in your images! But if your photos are seen as large prints, or you are simply a stickler for detail, then you will be happy with the R5’s 45 megapixels. (Indeed, you might wish to wait for the rumoured even higher megapixel Canon 5S!)
Nightscapes, and indeed all landscape photos by day or by night, is where you will see the benefit of more megapixels. Finer details in the foreground show up better. Images are less pixelated. In test images with all three cameras, the R5 did provide sharper images to be sure. But you do have to zoom in a lot to appreciate the improvement.
Resolution — lunar imaging
The Moon through a telescope is another good test of resolution. The above comparison shows how the R5’s smaller 4.4-micron pixels do provide much sharper details and less pixelation than the R6.
Of course, one could shoot at an even longer focal length to increase the “plate scale” with the R6. But at that same longer focal length the R5 will still provide better resolution, up to the point where its pixels are sampling more than what the atmospheric seeing conditions permit to be resolved. For lunar and planetary imaging, smaller pixels are always preferred, as they allow you to reach the seeing limit with shorter and often faster optical systems.
Resolution — deep sky
On starfields, the difference is not so marked. As I showed in my review of the R6, with “only” 20 megapixels the R6 can still provide detailed deep-sky images.
However, in comparing the three cameras above, with images taken at a focal length of 420mm, the R5 does provide sharper stars, with faint stars better recorded, and with less blockiness (i.e. “square stars”) on all the star images. At that focal length the plate scale with the R5 is 2.1 arc seconds per pixel. With the R6 it is 3.2 arc seconds per pixel.
The R5 is a good choice for shooting open and globular star clusters, or any small targets such as planetary nebulas, especially with shorter focal length telescopes. Bright targets will allow using lower ISOs, mitigating any of the R5’s extra noise.
With an 800mm focal length telescope, the plate scale with the R5 will be 1.1 arc seconds per pixel, about the limit most seeing conditions will permit resolving. With even longer focal length telescopes, the R5’s small pixels would be oversampling the image, with little gain in resolution, at least for deep-sky subjects. Lunar and planetary imaging can benefit from plate scales of 0.5 arc seconds per pixel or smaller.
CAN YOU CreatE resolution?
Now, one can argue that today’s AI-driven scaling programs such as ON1 Resize AI and Topaz Gigapixel AI can do a remarkable job up-sizing images while enhancing and sharpening details. Why buy a higher-megapixel camera when you can just sharpen images from a lower-resolution model?
While these AI programs can work wonders on regular images, I’ve found their machine-learning seems to know little about stars, and can often create unwanted artifacts.
In scaling up an R6 image by 200%, ON1 Resize AI 2022 made a mess of the stars and sky background. Topaz Gigapixel AI did a much better job, leaving few artifacts. But using it to double the R6 image in pixel count still produced an image that does not look as sharp as an original R5 image, despite the latter having fewer pixels than the upsized R6 image.
Yes, we are definitely pixel-peeping! But I think this shows that it is better to have the pixels to begin with in the camera, and to not depend on software to generate sharpness and detail.
The R5’s 45-megapixel sensor also makes possible its headline selling point when it was released in 2020: 8K movie recording, with movies sized 8192 x 4320 (DCI standard) or 7680 x 4320 (UHD standard) at 29.97 frames per second, almost IMAX quality.
Where the R6’s major selling point for me was its low-light video capability, the R5’s 8K video prowess was less important. Or so I thought. With testing, I can see it will have its place in astrophotography, especially solar eclipses.
Unlike the original Canon R and Rp, the R5 and R6 can shoot 4K movies sampled from the full width of their sensors, so there is no crop factor in the field of view recorded with any lens.
However, like the R6, the R5 also offers the option of a Movie Crop mode which samples a 4K movie from the central 4096 (4K-D) or 3840 (4K-U) pixels of the sensor. As I show above, this provides a “zoomed-in” image with no loss of resolution, useful when wide field of view is not so important as is zooming into small targets, such as for lunar and solar movies.
So what format produces the best resolution when shooting movies? As I show above, magnified frame grabs of the Moon demonstrate that shooting at 8K provides a much less pixelated and sharper result than either the 4K-Fine HQ (which creates a “High-Quality” 4K movie downsampled from 8K) or a standard 4K movie.
Shooting a 4K movie with the R6 also produced a similar result to the 4K movies from the R5. The slightly softer image in the R5’s 4K frame can, I think, be attributed more to atmospheric seeing.
Solar eclipse use
Shooting the highest resolution movies of the Moon will be of prime interest to astrophotographers when the Moon happens to be passing in front of the Sun!
That will happen along a narrow path that crosses North America on April 8, 2024. Capturing the rare total eclipse of the Sun in 8K video will be a goal of many. At the last total solar eclipse in North America, on August 21, 2017, I was able to shoot it in 4K by using a then state-of-the-art top-end Canon DSLR loaned to me by an IMAX movie production company!
And who knows, by 2024 we might have 100-megapixel cameras capable of shooting and recording the firehose of data from 12K video! But for now, even 8K can be a challenge.
However, do you need to shoot 8K to get sharp Moon, Sun or eclipse movies? The above shows the 8K frame-grab compared to the R5’s best quality full-frame 4K Fine, and the R5’s and R6’s 4K Movie Crop mode that doesn’t resample or bin pixels from the larger sensor to create a 4K movie. The Cropped movies look only slightly softer than the R5 at 8K, with less pixelation than the 4K Fine HQ movie.
When shooting the Sun or Moon through a telescope or long telephoto lens, the wide field of a full-frame movie might not be required, even to take in the two- or three-degree-wide solar corona around the eclipsed Sun.
However, if a wide field for the maximum extent of the outer corona, combined with sharp resolution is the goal, then a camera like the Canon R5 capable of shooting 8K movies will be the ticket.
And 8K will be ideal for wide-angle movies of the passage of the Moon’s shadow during any eclipse, or for moderate fields showing the eclipsed Sun flanked by Jupiter and Venus on April 8, 2024.
Like the R6, the R5 offers the option of shooting movies in Canon’s C-Log3 profile, which records internally in 10-bit, preserving more dynamic range in movies, up to 12 stops. The resulting movie looks flat, but when “colour graded” later in post, the movie records much more dynamic range, as I show above. Without C-Log3, the bright sunlit lunar crescent is blown out, as will be the Sun’s inner corona.
The bright crescent Moon with dim Earthshine is a good practice-run stand-in for the eclipsed Sun with its wide range of brightness from the inner to the outer corona.
Sample Moon Movies
For the full comparison of the R5 and R6 in my test shoot of the crescent Moon, see this narrated demo movie on Vimeo for the 4K movies, shot in various modes, both full-frame and cropped, with C-Log3 on and off.
Keep in mind that video compression in the on-line version may make it hard to see the resolution difference between shooting modes.
A “private link” 10-minute video on Vimeo demonstrating 4K video clips with the R5 and R6.
For a movie of the 8K footage, though downsized to 4K for the Vimeo version (the full sized 8K file was 29 Gigs!), see this sample movie below on Vimeo.
A “private link” video on Vimeo demonstrating 8K video clips with the R5.
Like the R6, the R5 can shoot at a dragged shutter speed as slow as 1/8-second. That slow shutter, combined with a fast f/1.4 to f/2 lens, and ISOs as high as 51,200 are the keys to shooting movies of the night sky.
Especially auroras. Only when auroras get shadow-casting bright can we shoot at the normal 1/30-second shutter speed of movies and at lower ISOs.
I was able to shoot a decent aurora one night from home with both the R5 and R6, and with the same fast TTArtisan 21mm f/1.5 RF lens. The sky and aurora changed in brightness from the time I shot with the R6 first to the R5 later. But even so, the movies serve as a look at how the two cameras perform for real-time aurora movies.
Auroras are where we need to shoot full-frame, for the maximum field of view, and at high ISOs. The R5’s maximum ISO is 51,200, while the R6 goes up to 204,800, though it is largely unusable at that speed for actual shooting, just for previewing scenes.
As expected, the R6 was much less noisy than the R5, by about two stops. The R5 is barely usable at ISO 51,200, while the R6 works respectably well at that speed. If auroras get very bright, then slower ISOs can be used, making the R5 a possible camera for low-light use, but it would not be a first choice, unless 8K auroras are a must-have.
Sample aurora Movies
For a narrated movie comparing the R5 and R6 at 4K on the aurora, stepping both through a range of ISO speeds, see this movie at Vimeo.
A “private link” video on Vimeo demonstrating 4K aurora clips with the R5 and R6.
For a movie showing the same aurora shot with the R5 at 8K, see this movie. However, it has been down-sized to 4K for on-line viewing, so you’ll see little difference between it and the 4K footage. Shooting at 8K did not improve or smooth noise performance.
A “private link” video on Vimeo demonstrating 8K aurora clips with the R5.
BATTERY LIFE — Stills and video
Canon’s new LP-E6NH battery supports charging through the USB-C port and has a higher 2130mAh capacity than the 1800mAh LP-E6 batteries. However, the R5 is compatible with the older batteries.
On mild nights, I found the R5 ran fine on one battery for the 3 to 4 hours needed to shoot a time-lapse sequence, or set of deep-sky images, with power to spare. Now, that was with the camera in “Airplane Mode,” which I always use regardless, to turn off the power-consuming WiFi and Bluetooth, which I never use on cameras.
As I noted with the R6, for demanding applications, especially in winter, the R5 can be powered by an outboard USB power bank that has Power Delivery or “PD” capability.
The exception for battery use is when shooting videos, especially 8K. That can drain a battery after an hour of recording, though it takes only 10 to 12 minutes of 8K footage to fill a 128 gigabyte card. While less than half that length will be needed to capture any upcoming total eclipse from diamond ring to diamond ring, the result is still a massive file.
More critically, the R5 is also infamous for overheating and shutting down when shooting 8K movies, after a time that depends on how hot the environment is. I found the R5 shot 8K or 4K Fine HQ for about 22 minutes at room temperature before the overheat warning first came on, then shut off recording two or three minutes later. Movie recording cannot continue until the R5 cools off sufficiently, which takes at least 10 to 15 minutes.
That deficiency might befoul unwary eclipse photographers in 2024. The answer for “no-worry” 8K video recording is the Canon R5C, the video-centric version of the R5, with a built-in cooling fan.
Features and usability
While certainly not designed with astrophotography in mind, the R5 has several hardware and firmware features that are astrophoto friendly.
Like all Canon cameras made in the last few years, the R5 has Canon’s standard articulated screen, which can be angled up for convenient viewing when on a telescope. It is also a full touch screen, with all important camera settings and menus adjustable on screen, good for use at night.
With 2.1 million dots, the R5’s rear screen has a higher resolution than the 1.62-million-dot screen of the R6, and much higher than the 1 million pixels of the Rp’s screen, but is the same resolution as in the R and Ra.
The R5, like the original R, has a top backlit LCD screen for display of current camera settings, battery level and Bulb timer. The lack of a top screen was one of my criticisms of the R6.
Yes, the hardware Mode dial of the R6 and Rp does make it easier to switch shooting modes, such as quickly changing from Stills to Movie. However, for astrophotography the top screen provides useful information during long exposures, and is handy to check when the camera is on a telescope or tripod aimed up to the sky, without spoiling dark adaptation. I prefer to have one.
The R5’s remote shutter port, used for connecting external intervalometers or time-lapse motion controllers, is Canon’s professional-grade three-pronged N3 connector. It’s sturdier than the 2.5mm mini-phono plug used by the Rp, R and R6. It’s a plus for the R5.
As with all new cameras, the R5’s USB port is a USB-C type. A USB-C cable is included.
Like the R6, the R5 has a dedicated magnification button on the back panel for zooming in when manually focusing or inspecting images. In the R and Ra, that button is only on the touch panel rear screen, where it has to be called up by paging to that screen, an inconvenience. While virtual buttons on a screen are easier to see and operate at night than physical buttons, I find a real Zoom button handy as it’s always there.
To handle the high data rates of 8K video and also 4K video when set to the high frame rate option of 120 fps, one of the R5’s memory card slots requires a CFexpress Type B card, a very fast but more costly format.
As I had no card reader for this format, I had to download movies via a USB cable directly from the camera to my computer, using Canon’s EOS Utility software, as Adobe Downloader out of Adobe Bridge refused to do the job. Plan to buy a card reader.
In the menus, you can choose to record video only to the CFexpress, and stills only to the SD card, or both stills and movies to each card for a backup, with the limitation that 8K and 4K 120fps won’t record to the SD card, even very fast ones.
Unlike the Canon R and Ra (which both annoyingly lack a built-in intervalometer), but like the R6, the R5 has an Interval Timer in its firmware. This can be used to set up a time-lapse sequence, but with exposures only up to the maximum of 30 seconds allowed by the camera’s shutter speed settings, true of most in-camera intervalometers. Even so, this is a useful function for simple time-lapses.
As with most recent Canon DSLRs and DSLMs, the R5 also includes a built-in Bulb Timer. This allows setting an exposure of any length (many minutes or hours) when the camera is in Bulb mode. However, it cannot be combined with the Interval Timer for multiple exposures; it is good only for single shots. Nevertheless, I find it useful for shooting long exposures for the ground component of nightscape scenes.
While Canon cameras don’t have Custom Function buttons per se (unlike Sonys), the R5’s various buttons and dials can be custom programmed to functions other than their default assignments. I assign the * button to turning on and off the Focus Peaking display and, as shown, the AF Point button to a feature only available as a custom function, one that temporarily brightens the rear screen to full, good for quickly checking framing at night.
A handy feature of the R5 is the ability to add an audio notation to images. You shoot the image, play it back, then use the Rate button (if so assigned) to record a voice memo of up to 30 seconds, handy for making notes in the field about an image or a shoot. The audio notes are saved as WAV files with the same file number as the image.
Like other EOS R cameras, the R5 has this notorious “feature” that trips up every new user who attaches their Canon camera to a telescope or manual lens, only to find the shutter suddenly doesn’t work. The answer is to turn ON “Release Shutter w/o Lens” found buried under Custom Functions Menu 4. Problem solved!
I provide more details of other features and settings of the R5, many of which are common to the R6, in my review of the R6 here.
No question, the Canon R5 is costly. Most buyers would need to have very good daytime uses to justify its purchase, with astrophotography a secondary purpose.
That said, other than low-light night sky videos, the R5 does work very well for all forms of astrophotography, providing a level of resolution that lesser cameras simply cannot.
Nevertheless, if it is just deep-sky imaging that is of interest, then you might be better served with a dedicated cooled-sensor CMOS camera, such as one of the popular ZWO models, and the various accessories that need to accompany such a camera.
But for me, when it came time to buy another premium camera, I still preferred to have a model that could be used easily, without computers, for many types of astro-images, particularly nightscapes, tracked wide-angle starfields, as well as telescopic images.
Since buying the R5, after first suspecting it would prove too noisy to be practical, it has in fact become my most used camera, at least for all images where the enhanced red sensitivity of the EOS Ra is not required. But for low-light night videos, the R6 is the winner.
However, to make use of the R5’s resolution, you do have to match it with sharp, high-quality lenses and telescope optics, and have the computing power to handle its large files, especially when stitching or stacking lots of them. The R5 can be just the start of a costly spending spree!
However, the reward was the sight of the reddened Moon from one of my favourite locations in Alberta, Reesor Lake, in Cypress Hills Interprovincial Park.
The eclipse in question was the total lunar eclipse of May 15/16, 2022. As with any eclipse, planning starts with a look at the weather forecasts, or more specifically cloud forecasts.
A few days prior, conditions didn’t look good from my home, to the west of the red marker.
But as the chart from the app Astrospheric shows, very clear skies were forecast for southeast Alberta, in the Cypress Hills area, where I have shot many times before.
Except as eclipse evening drew closer, the forecast got worse. Now, the clouds were going to extend to my chosen site, with a particularly annoying tongue of cloud right over my spot. Clouds were going to move in just as the total eclipse began. Of course!
I decided to go for it anyway, as the Moon would be to the east, in the direction of the clear skies. It didn’t need to be clear overhead. Nor did I want to drive any farther than I really needed, especially to another location with an unknown foreground.
The spot I chose was one I knew well, on the west shore of scenic Reesor Lake, near the Alberta/Saskatchewan border, but on the Alberta side of Cypress Hills Interprovincial Park.
Handily, TPE provides moonrise times and angles for the chosen location, as well as eclipse times for that time zone.
The companion app, TPE 3D, provides a preview of the scene in 3D relief, with the hills depicted, as a check on Moon altitude and azimuth with respect to the horizon below.
As you can see the simulation matched reality quite well, though the image below was from an earlier time than the simulation, which was for well after mid-totality.
However, true to the predictions, clouds were moving in from the west all during the eclipse, to eventually obscure the Moon just as it entered totality and became very dim. Between the clouds and the dark, red Moon, I lost sight of it at totality. As expected!
Below is my last sighting, just before totality began.
However, I was content at having captured the eclipse from a photogenic site. More images of a complete eclipse would have been nice, but alas! I still consider the chase a success.
Just for fun, I shot a quick panorama of three segments, and it turned out to be my favourite image from the eclipse, capturing the scene very well. Pelicans and geese were plying the calm waters of the lake. And owls were hooting in the woods. It was a fabulous evening!
Before departing, I took my customary “trophy” shot, of the eclipse hunter having bagged his game.
Interestingly, this eclipse was a close repeat of one 19 years earlier to the day, because of the so-called Metonic Cycle where eclipses of the Sun and Moon repeat at 19-year intervals on the same calendar day, at least for 2 or 3 cycles.
On May 15, 2003, we also had a total lunar eclipse in the early evening, with the eclipsed Moon rising into a spring twilight sky. I also chased clear skies for that one, but in the opposite direction from home, to the southwest, to the foothills. At that time it was all film, and medium format at that.
So it was another (partially!) successful eclipse chase.
The next opportunity is on the night of November 7/8, 2022, a time of year not known for clear skies!
Just once I would like to see one from home, to make it easier to shoot with various telescopes and trackers, as the reddened Moon will be west of the photogenic winter Milky Way, and very close to the planet Uranus. Plus for me in Alberta the November eclipse occurs in the middle of the night, making a home eclipse much more convenient. After that, the next chance is March 13/14, 2025.
But no matter the eclipse, I suspect another chase will be in order! It just wouldn’t be a lunar eclipse without one.
Two total eclipses of the Moon, an all-planet array across the sky, and a fine close approach of Mars highlight the astronomical year of 2022.
In this blog, I provide my selection of the best sky sights of 2022. I focus on events you can actually see, and from North America. I also emphasize photogenic events, such as gatherings of the Moon and planets at dawn or dusk, and the low Full Moons of summer.
The sky charts are for my longitude in Alberta and my home latitude of 51° N, farther north than many readers will likely live. From more southerly latitudes in North America, the low planet gatherings at dawn or dusk will be more obvious, with the objects higher and in a darker sky than my charts depict.
Feel free to share the link to my blog, or to print it out for reference through the year.
Highlights: Lunar Eclipses, Planet Array and Mars
As in 2021, this year we have two lunar eclipses, both total this year, six months apart in May and in November. On the night of May 15/16 eastern North America gets the best view of a deep total eclipse that lasts 85 minutes. Six lunar cycles later, western North America gets the best view of another 85-minute-long total lunar eclipse.
The year begins with four planets in the evening sky, but not for long. They all soon move into the morning sky for the rest of the first half of 2022. In fact, in late June we have the rare chance to see all five naked eye planets lined up in order (!) across the morning sky.
The “star” planet of 2022 is Mars, as it reaches one of its biennial close approaches to Earth, and a decent one at that, with its disk relatively large and the planet high in the winter sky, making for excellent telescope views. The night Mars is directly opposite the Earth and at its brightest coincides with a Full Moon, which just happens to also pass in front of Mars that night! That’s a remarkable and rare event to round out a year of stargazing.
The RASC has also partnered with Firefly Books to publish a more popular-level guide to the coming year’s sky for North America, as the 2022 Night Sky Almanac, authored by Canadian science writer Nicole Mortillaro. It provides excellent monthly star charts to help you learn the sky.
The year begins with a chance to see four planets together at dusk. But catch them quick!
January 4 — Mercury, Venus (just!), Jupiter and Saturn, plus the Moon
Venus is sinking out of sight fast, as it approaches its January 8 conjunction with the Sun, putting it out of sight. But Mercury is climbing higher, approaching its January 7 greatest angle away from the Sun.
This night the waxing crescent Moon appears below Saturn. It was below Mercury on January 3, and will be below Jupiter on January 5. On January 13, Mercury shines 3.5 degrees (°) below Saturn, just before both disappear close to the Sun.
January 17 — The 2022 Mini-Moon
The Full Moon this night is the most distant, and therefore the smallest, of 2022. Shoot it and the Full Moon of July with identical gear to collect a contrasting pair of Mini and Super Moons, as above.
January 29 — Waning Moon and Morning Planets
By the end of January, Mercury and Venus have both moved into the morning sky, where they join Mars. The waning crescent Moon appears below magnitude 1.5 Mars this morning, as the famed red planet begins its fine appearance for 2022.
The main planet action migrates to the morning sky, while Zodiacal Light season begins in the evening.
February 16 — Mercury As a Morning Star
Though not a favourable elongation for northern latitudes, on February 16 Mercury reaches its highest angle away from the Sun low in the eastern dawn, below Venus and Mars, with Venus having just reached its greatest brilliancy (at a blazing magnitude -4.9!) on February 12, shining above much dimmer Mars. (Magnitude 0 to 1 is a bright star; magnitude 6 is the faintest naked-eye star; any magnitude of -1 to -5 is very bright.)
While at magnitude 0, elusive Mercury shines a magnitude and a half brighter than Mars, Mercury’s lower altitude will make it tougher to see. Use binoculars to pick it out. But Venus remains a brilliant and easy “morning star” for the next few months.
February 18 — Zodiacal Light Season Begins in the Evening
From sites away from light pollution look for a faint glow of light rising out of the southwest sky on any clear evening for the next two weeks with no Moon. This glow is caused by sunlight reflecting off cometary dust particles in the inner solar system. The next moonless window for the evening Zodiacal Light is March 20 to early April. Spring is the best season for seeing and shooting the Light in the evening sky.
February 27 — Moon Joins the Morning Planet Party
The waning crescent Moon appears very low below Mars and Venus, with Mercury still in view, and Saturn just beginning to emerge from behind the Sun.
Equinox brings a favourable season for great auroras, while the morning planets begin to cluster in the east.
March 1 on — Prime Aurora Season Begins
While great auroras can occur in any month, statistically the best displays often occur around the two equinoxes in spring and autumn. No one can predict more than 12 to 48 hours ahead (and still with a great deal of uncertainty) when a display will be visible from mid-latitudes. But watch sites such as SpaceWeather.com for heads-up notices.
March 1 on — Flaring Geosat Season Begins
In the weeks prior to the spring equinox, and in the few weeks after the autumn equinox, the string of communication satellites in geostationary orbit catch the sunlight and flare to naked-eye brilliance. Long-exposure tracked photos of the area below Leo (in spring, as here) will catch them as streaks, as the camera follows the stars causing the stationary satellites to trail.
March 12 — Venus and Mars in Conjunction
Venus and Mars reach their closest separation 4° apart low in the southeastern dawn sky.
March 20 — Equinox at 11:33 a.m. EDT
Spring officially begins for the northern hemisphere, autumn for the southern, as the Sun crosses the celestial equator heading north. Today, the Sun rises due east and sets due west, great for urban photo ops.
March 27 — Moon and a Planetary Triangle
The waning crescent Moon appears to the west of Venus and Mars, with Venus about 2° above Saturn. The view will be better the next morning, March 28, with the thin Moon directly below the close pairing of Venus and Saturn. But the Moon will be even lower in the sky, making it more difficult to sight.
Mercury puts on its best evening show of 2022, near the Pleiades, and with a possible comet nearby. The month ends with a very close conjunction of Venus and Jupiter at dawn.
April 1 — Milky Way Arch Season Opens
With the Moon out of view, the next two weeks bring good nights to shoot panoramas of the bright summer Milky Way as an arch across the sky, with the galactic core in view to the south. Catching the arch takes a very late-night shoot in early April. But the Milky Way moves into prime position two hours earlier each month.
April 5 — Mars and Saturn 1/2° apart
The two planets appear almost the same brightness as a close “double star” in the dawn, not far from brighter Venus. Mars and Saturn will also be close the morning before, on April 4.
April 27 — Moon Joins Venus and Jupiter
Jupiter is now emerging from behind the Sun to meet up with Venus, for a grouping of the sky’s two brightest planets. On this morning the waning Moon appears 4.5° below the pair.
April 29 — Mercury Appears Beside the Pleiades
Just as Mercury reaches its greatest angle away from the Sun for its best evening appearance of 2022, it also appears just 1° away from the famous Pleiades star cluster low in the west.
April 30 — Venus and Jupiter in Close Conjunction
This is an early morning sight well worth getting up for! Venus passes only 1/3° below Jupiter this morning, but low in the eastern dawn sky. They will be almost as close on May 1.
April 30 — A Bonus Comet?
Comet PanSTARRS (C/2021 O3) might become bright enough to be a binocular object, and a photogenic target, right next to the Pleiades and Mercury pairing. Maybe! Some predictions suggest this comet could fizzle and break up earlier in April. Even if the comet survives and performs, you’ll need a very clear sky to the northwest to catch this rare sight.
On May 15-16 a totally eclipsed Moon shines red in the south at midnight for eastern North America, and in the southeast after sunset from the west.
May 15-16 — Total Eclipse of the Moon
The first of two total lunar eclipses in 2022 can be seen in its entirety from eastern North America, with totality beginning at 11:30 p.m. EDT on May 15 and lasting 85 minutes until 12:55 a.m. EDT. At mid-eclipse just after midnight from eastern North America the Moon will appear nearly due south, with the summer Milky Way to the east, shining brightly as the sky darkens during totality. Travel to a dark site to see and shoot the Moon and Milky Way.
Those in western North America see the totally eclipsed Moon rising into the southeast with some portion of the eclipse in progress, as depicted above. Once the sky darkens, the reddened Moon should become visible. Over a suitable landscape this should be a photogenic scene, though with the core of the Milky Way not yet risen. But a Milky Way arch panorama with a red Moon at one end will be possible. Choose your scenic site well!
See Fred Espenak’s EclipseWise.com page for details on timing and viewing regions. The dark region on this map does not see any of this eclipse.
May 18 — Red Planet Meets Blue Planet
Mars passes just 1/2° south of Neptune this morning, though both planets are very low in the east. They will appear close enough to frame in a telescope (the red circle is 1° wide).
May 24 — Moon with Mars and Jupiter
As it does every month in early 2022, the waning crescent Moon joins the morning planets, on this day grouping with Mars and Jupiter before dawn.
May 27 — Moon with Venus, plus Mars and Jupiter Close
Later that week the thinner waning Moon passes 4° below bright Venus, still shining at magnitude -4. But higher up Mars and Jupiter are reaching a close conjunction, passing about 1/2° apart on May 28 and May 29. Mars is still a dim magnitude +0.7; Jupiter is at -2.2.
Noctilucent cloud season begins for northerners, as does prime Milky Way core season for southerners. But the unusual sight is the line of all five naked eye planets, and in order!
June 1 on — Milky Way Core Season at its Prime
In early June with no Moon to interfere, and monthly for the next four months, the Milky Way core is ideally placed to the south through the night for nightscapes. However, for those at more northern latitudes the sky in June doesn’t get dark enough to make deep Milky Way shots feasible.
June 1 on — Noctilucent Cloud Season Begins
Instead, northerners are rewarded by the occasional sight of noctilucent clouds to the north through June and well into July (even into August for sub-arctic latitudes). The Sun illuminates these high-altitude electric-blue clouds during the weeks around the summer solstice. However, there is no predicting on what night a good display will appear.
June 14 — First of the Summer Supermoons
The Moon is full on the night of June 14-15, when it also reaches one of its closest perigees (closest approach to Earth) of 2022. In modern parlance, that makes it a “supermoon.” It will look impressive shining low in the south all night, with the low-altitude “Moon illusion” making it appear even larger. It is a good night for nightscapes with the Moon, though exposures are a challenge — try blending short exposures for the lunar disk with long exposures for the sky and ground.
June 21 — Solstice at 5:14 a.m. EDT
Summer officially begins for the northern hemisphere, winter for the southern, as the Sun reaches its most northerly position above the celestial equator. The Sun rises farthest to the northeast and sets farthest to the northwest, and the length of daylight is at its maximum.
June 24 — All Planets in a Row
As fast-moving Mercury rises into view at dawn in mid-June, it completes the set to provide the rare chance to see all five naked eye planets — Mercury, Venus, Mars, Jupiter and Saturn — in a row along the ecliptic, the path of the planets. Even more fun, they are in the correct order out from the Sun! The scene shown here depicts the morning of June 24, when the Moon sits between Venus and Mars, just where it should be in order of distance from the Sun as well.
A panorama of several stitched images will be best for capturing the scene which spans 120°. Uranus and Neptune are there, too, though not in order and faint enough (below naked eye brightness) they will be tough to capture in a wide-angle scene. Long exposures with a tracker might do the job! But by the time Mercury rises high enough, the sky might be getting too bright to nab the faintest planets.
June 26 — Inner World Gathering
The select club of just inner worlds gathers for a meeting this morning, with the waning crescent Moon 2.5° above Venus. The rising stars of Taurus serve as a fine backdrop in the dawn twilight.
Once the pesky full supermoon gets out of the way, the heart of Milky Way season will be infull swing.
July 13 — Second of the Summer Supermoons
It will be a battle of summer supermoons in 2022! But July’s Moon wins on a technicality, as it is ever so slightly closer (by about 200 km) than the June Moon. It also appears slightly farther south, so lower in the sky than a month before. This is a good night for lunar (looney?) photo ops, though don’t expect to see the Milky Way as shown here — moonlight will wash it out.
July 26 — Dawn Moon and Morning Star
Another photo op comes on July 26 when the waning crescent Moon passes 3° above Venus, still bright at magnitude -3.8. The last week of July and the first week of August are prime weeks for shooting the Milky Way core to the south over scenic nightscapes, assuming we get clear skies free of forest fire smoke.
The popular Perseid meteors are mooned out, but late in the month under dark skies, the Milky Way reigns supreme.
August 1 — Red Planet Meets Green Planet
As it did in May, Mars meets up with an outer planet, passing close enough to Uranus this night for both to appear in a low-power telescope field (the red circle is 2° wide).
August 12-13 — Perseid Meteor Shower Peaks
The annual and popular Perseid meteor shower peaks tonight, but with a nearly Full Moon in Aquarius (as shown above) lighting the sky all night. Under a transparent sky, you’ll still see some bright meteors radiating from Perseus in the northeast. But you’ll need to be patient, as bright meteors are infrequent. But why not enjoy a moonlit summer night under the stars anyway?
August 14-15 — Saturn at Opposition
Saturn is at its closest and brightest for 2022 tonight, rising at sunset and shining due south in eastern Capricornus in the middle of the night. Through a telescope the rings appear tipped at an angle of 13°, about half the maximum possible at Saturnian solstices. The northern face of the rings is tipped toward us.
August 16 on — Prime Milky Way Season
After it spoils the Perseids, the waning gibbous Moon takes a long time to get out of the way. As it does so, mid-August brings some good nights to shoot the Milky Way to the south as the rising waning Moon to the east illuminates the landscape with warm “bronze hour” lighting. By the last week of August, nights are finally moonless enough for an all-night dark-sky shoot.
August 25 — Thin Moon Above Venus
Those enjoying an all-nighter under the stars on August 24 will be rewarded with the sight of the thin waning Moon and Venus rising together at dawn on August 25. They will be 5° apart in the morning twilight, against the backdrop of the winter stars rising.
It’s Harvest Moon time, with this annual special Full Moon coming early before the equinox this year.
September 1 on — Prime Aurora Season Begins
As in spring, some of the best weeks for sighting auroras traditionally occur around the autumn equinox. Solar activity is on the rise in 2022, heading toward an expected solar maximum in late 2024 or 2025. So we can expect some good shows this year, including some that should extend south into the northern half of the lower 48 in the U.S.
September 10 — Full “Harvest” Moon
Occurring 12 days before the equinox, this is the closest Full Moon to the equinox, making it the official Harvest Moon of 2022. With it occurring early this year, the Harvest Moon will rise well south of due east at sunset and set well south of due west at sunrise on September 11.
Autumn officially begins for the northern hemisphere, spring for the southern, as the Sun crosses the celestial equator heading south. As in March, the Sun rises due east and sets due west for photo ops on east-west aligned roads, as above.
September 23 — Zodiacal Light Season Begins in the Morning
With no Moon for the next two weeks, from sites away from light pollution look to the pre-dawn sky for a faint glow of light rising out of the east before twilight brightens the morning sky. The end of October brings another moonless morning window of opportunity for the Zodiacal Light.
September 26-27 — Jupiter at opposition
Jupiter, now in southern Pisces, reaches its closest and brightest for 2022 tonight, also rising at sunset and shining due south in the middle of the night. Jupiter has now moved far enough along the ecliptic to place it high in the sky for northern observers, providing us with sharper telescope views than we’ve had for many years.
Mercury rises into the dawn, while the Moon occults the planet Uranus.
October 8 — Mercury at Its Morning Best
This is the best time to sight Mercury in the morning, as it reaches its greatest angle away from the Sun today, while the steep angle of the ecliptic on autumn mornings swings the inner planet up as high and clear from horizon haze it can get for the year.
October 11 — Moon Hides Uranus
While many observers might not have seen Uranus, here’s a chance to see it, then not see it! The waning gibbous Moon passes in front of magnitude 5.7 Uranus this night, occulting the planet for about an hour around midnight. Exact times will vary with location. Seeing the planet reappear from behind the dark limb of the Moon, as shown here, will be the easiest sighting, but a telescope will be essential.
October 21 — Orionid Meteor Shower Peaks
With both the Perseids and Geminids mooned out this year, the weaker but reliable Orionids remain as perhaps the best meteor shower of 2022. The meteors (expect only about 10 per hour) all appear to radiate from northern Orion, which doesn’t rise until just before midnight. Mars shines bright above the radiant point.
October 25 — Partial Solar Eclipse for Europe
While my list is aimed at North American stargazers, I should mention the partial eclipse of the Sun (there are no total solar eclipses this year) that observers across parts of Asia, Africa, Europe and the U.K. (as shown above) can see.
At maximum eclipse from Siberia about 86% of the Sun’s disk will be covered. No part of the eclipse is visible from North America. For details, see the page at EclipseWise.com.
October 30 — Mars Begins Retrograde Motion
Mars stops its eastward motion this night and begins to retrograde westward for the next two months centred on the date of opposition, December 7. It then stops retrograding and resumes its prograde motion on January 12, 2023. Naked-eye Mars watchers can follow the changing position of Mars easily, using the stars of Taurus, including yellowish Aldebaran below, as a guide.
The second total lunar eclipse of 2022 brings a red Moon to the skies over western North America.
November 8 — Total Eclipse of the Moon
In a mirror-image of the May eclipse, this eclipse also lasts 85 minutes, but can be seen best from western North America. From the east, the Moon sets at dawn with some portion of the eclipse in progress.
But from the west the Moon is fully eclipsed during the wee hours of November 8, with the Moon sitting west of the winter Milky Way, making for good wide-angle photos.
The Moon sits just a degree west of Uranus during totality. From Asia the eclipsed Moon actually passes in front of the planet for a rare eclipse and occultation combination. We have to be content with seeing the green planet east of the reddened Moon. A telescope with 600mm focal length should nicely frame the pairing.
The total phase of the eclipse begins at 5:16 a.m. EST (3:16 a.m. MST) and ends at 6:41 a.m. EST (4:41 a.m. MST).
For details see Fred Espenak’s EclipseWise site. As above, the dark region on this map does not see any of this lunar eclipse.
November 17 — Leonid Meteor Shower Peaks
As with the Orionids, this is normally a weak shower, but this year we have to be content with watching the weak showers. The waxing crescent Moon shining below Leo (as shown above) shouldn’t hinder observations of the Leonids too much. But with Leo not rising until late, this is another shower that requires a long, late night to observe.
Mars reaches its closest point to Earth since October 2020, with the Moon occulting Mars on peak night.
December 1 — Mars at Its Closest
Mars is closest to Earth this night, at 81 million kilometres away. This is not as close as it was in October 2020 when it was 62 million km away. Its disk then appeared large, at 22.5 arc seconds across. Maximum size on this night is 17.2 arc seconds, still good enough for fine telescope views.
Take the opportunity on every clear night to view Mars, as this is as good as we will see the planet until the early 2030s. As it happens, the most interesting side of Mars, featuring the prominent dark Syrtis Major region and bright Hellas basin (shown above in a simulated telescope view), faces us in North America on closest approach night.
Wide-angle views and photos will also be impressive, with reddish Mars shining brightly at magnitude -1.8 in Taurus with its photogenic star clusters, and near the winter Milky Way.
December 7/8 — Mars at Opposition
This is the night Mars is officially at opposition, meaning it lies directly opposite the Sun and shines at its brightest. As it rises at sunset and into the early evening (as above), it is accompanied by the Full Moon, also at opposition this night, as all Full Moons are.
By midnight (above), the Moon and Mars lie due south high in the sky. If you can keep warm and keep an eye on Mars over this long night of opposition, you’ll see surface features on Mars change as the planet rotates, bring new areas into view, with the fork-shaped Sinus Meridiani region rotating into view as triangular Syrtis Major rotates out of sight.
December 7 — Moon Occults Mars
This is very rare! On opposition night, not only does the Full Moon appear close to Mars, it actually passes in front of it during the early evening for North America. The occultation lasts about an hour, and exact times will vary with location. Binoculars will show the event, as will even the naked eye. But the best view will be through a telescope (as above), where you will be able to see the edge of the Moon cover Mars over about half a minute. Ditto on the reappearance. This is an event worth traveling to seek out clear skies if needed.
December 13-14 — Geminid Meteor Shower Peaks
The most prolific meteor shower of the year peaks with a waning gibbous Moon rising about 10 p.m. local time (as above), lighting the sky for the rest of the night. But the early evening is dark, and with Gemini just rising we might see some long Earth-grazing fireballs from the Geminids. So certainly worth a watch on a cold December night.
December 21 — Solstice at 4:48 p.m. EST
Winter officially begins for the northern hemisphere, summer for the southern, as the Sun reaches its most southerly position below the celestial equator. The Sun rises farthest to the southeast and sets farthest to the southwest, and the length of daylight is at its minimum.
December 24 — Inner Planets at Dusk
On Christmas Eve the waxing crescent Moon joins Mercury and Venus low in the southwest evening twilight. Mercury is three days past its greatest elongation, so is easier to see than usual, though it will be three and a half magnitudes fainter than magnitude -3.9 Venus.
December 28 — Mercury and Venus in Conjunction
This evening, descending Mercury passes 1.5° above Venus, now ascending into the evening twilight sky. Venus is just beginning what will be a spectacular evening appearance for early 2023, featuring close conjunctions with Saturn (on January 22, 2023) and Jupiter (on March 1, 2023).
It’s been over 10 years since I’ve last had the luxury of observing an eclipse of the Moon from the comfort of home. Once again, a chase was needed.
During the post-midnight wee morning hours, the Moon was set to once again pass through the Earth’s shadow, this time presenting us with a deep partial eclipse, with 97% of the Full Moon’s disk immersed in the umbra and deep red.
Every lunar eclipse I’ve seen from Alberta since December 2010 I’ve had to chase to find clear skies. While the chases were all successful, this time I was hoping to stay home and enjoy the eclipse without a long drive to seek clear skies, and to then employ a telescope to shoot the Moon in close-up. In the days before the eclipse, the forecasts changed daily.
On the day before the eclipse, things looked bad, with high clouds forecast for home.
It looked like a trip to north-central Alberta was warranted, perhaps to Wainwright. But rather than book a motel, I decided to wait to see if the forecast might improve. And sure enough it did.
By the morning of eclipse day, prospect for clear skies from home looked better Or perhaps a short drive east would suffice. With luck!
But by the evening of the eclipse, clouds were not cooperating. The actual views from satellites showed lots of cloud over my area (as the view out the door confirmed!), and it didn’t look like the clouds were going away.
But as the previous forecasts called for, clear skies were to be found to the north. So at 11:30 pm, with the eclipse starting in less than an hour, I packed up the car and headed north to as far as I could get — and hopefully as far as I need to get — to be assured of clear skies.
It worked! The eclipse was well underway as I made my way north, stopping to check its progress and the state of the clouds. As expected, about 90 minutes north I drove out from under the clouds you can see to the south in the photo above, where I had come from.
I chose a side road and pull off near Rowley, Alberta. I had enough time to set up three cameras, two on polar-aligned trackers to take longer, wide-field images of the Moon amid the stars, plus the static camera for the selfies.
The red Moon below the blue Pleiades was the unique sight at this eclipse. It can only happen if an eclipse occurs in mid-November and that won’t happen for another 19 years, on November 18, 2040, in a total eclipse visible only from the eastern hemisphere.
After some mid-eclipse equipment woes — a tracker deciding to come loose from the tripod, and a lens that refused to focus — I also took some wider shots of the Moon among the stars of Taurus.
Despite writing an extensive blog on how to shoot this eclipse, it did prove to be more of a challenge than I had anticipated. The portion of the Moon outside the umbra, even at mid-eclipse, remained very bright, and overexposed and flared in the frames with long enough shutter speeds to record the stars. A full total eclipse is easier to shoot!
However, I can count this eclipse chase as a success. Of all the total (or near total in this case) lunar eclipses visible from my area of the world since 2001, I’ve seen them all. But almost all required a chase.
Will that be the case next year? We have two total lunar eclipses in 2022: on May 15 (with the Moon rising at eclipse time as seen from here in Alberta), and again six lunar cycles later on the morning of November 8, 2022, which is 12 lunar cycles after this most recent eclipse. We are in the middle of a nice run of 4 lunar eclipses, three total and one near-total.
On the night of November 18/19 eclipse fans across North America can enjoy the sight of the Moon turning deep red. Here’s how to capture the scene.
Seeing and shooting this eclipse will demand staying up late or getting up very early. That’s the price to pay for an eclipse everyone on the continent can see.
Also, this is not a total eclipse of the Moon. But it’s the next best thing, a 97% partial eclipse – almost total! So the main attraction — a red Moon — will still be front and centre.
CLICK ON AN IMAGE to bring it up full screen for closer inspection.
NOT QUITE TOTAL
At mid-eclipse 97% of the disk of the Full Moon will be within Earth’s dark umbral shadow, and should appear a bright red colour to the eye and even more so to the camera. A sliver of the southern edge of the Moon will remain outside the umbra and will appear bright white, like a southern polar cap on the Moon.
While some references will say the eclipse begins at 1:01 am EST, that’s when the Moon first enters the outer lighter penumbral shadow. Nothing unusual can be seen at that point, as the darkening of the Moon’s disk by the penumbra is so slight, you won’t notice any difference over the normally bright Full Moon.
It isn’t until the Moon begins to enter the umbra that you can see a dark bite being taken out of the edge of the Moon.
WHAT TO SEE
At mid-eclipse the Full Moon will look deep red or perhaps bright orange — the colours can vary from eclipse to eclipse, depending on the clarity of the Earth’s atmosphere through which the sunlight is passing to light the Moon. The red is the colour of all the sunsets and sunrises going on around the Earth during the eclipse.
The unique aspect of this eclipse is that for the 15 to 30 minutes around mid-eclipse we might see some unusual colour gradations at the edge of the umbral shadow, from sunlight passing through Earth’s upper atmosphere and ozone layer. This can tint the shadow edge blue or even green.
WHERE CAN THE ECLIPSE BE SEEN?
The last lunar eclipse six months ago on the morning of May 26, 2021 (see my blog here) was visible during its total phase only from western North America, and then only just. However, this eclipse can be seen from coast to coast.
Only from the very easternmost points in North America does the Moon set with the eclipse in progress, but during the inconsequential penumbral phase. All of the umbral phase is visible from the Eastern Seaboard, though the last stages will be in progress with the Moon low in the west in the pre-dawn hours. But that positioning can make for photogenic sight.
WHEN IS THE ECLIPSE?
The show really begins when the Moon begins to enter the umbra at 2:18 am EST (1:18 am CST, 12:18 am MST, 11:18 pm PST).
But note,these times are for the night of November 18/19. If you go out on the evening of November 19 expecting to see the eclipse, you’ll be sadly disappointed as you will have missed it. It’s the night before!
The eclipse effectively ends at 5:47 am EST (4:47 am CST, 3:47 am MST, 2:47 am PST) when the Moon leaves the umbra. That makes the eclipse 3 1/2 hours long, though the most photogenic part will be for the 15 to 30 minutes centred on mid-eclipse at 4:03 am EST (3:03 am CST, 2:03 am MST, 1:03 am PST).
WHERE WILL THE MOON BE?
The post-midnight timing places the Moon at mid-eclipse high in the south to southwest for most of North America, just west (right) of the winter Milky Way and below the distinctive Pleiades star cluster.
The high altitude of the Moon (some 60º to 70º above the horizon) puts it well above haze and murk low in the sky, but makes it a challenge to capture in a frame that includes the landscape below for an eclipse nightscape.
ASTRONOMY 101: The high altitude of the Moon is a function of both the eclipse timing in the middle of the night and its place on the ecliptic. The Full Moon is always 180° away from the Sun. So it sits where the Sun was six months earlier, in this case back in May, when the high Sun was bringing us warmer and longer days. Winter lunar eclipses are always high; summer lunar eclipses are always low, the opposite of what the Sun does.
From eastern North America the Moon appears lower in the west at mid-eclipse, making it easier to frame above a landscape. For example from Boston the Moon is 30º up, lending itself to nightscape scenes.
However, the sky will still be dark. To make use of the darkness to capture scenes which include the Milky Way, I suggest making the effort to travel away from urban light pollution to a dark sky site. That applies to all locations. Yes, that means a very long night!
PHOTO OPTIONS 1 — CAMERA ON A FIXED TRIPOD
With just a camera on a tripod, if you are on the East Coast (I show Boston here) it will be possible to frame the eclipsed Moon above a landscape with a 24mm lens (assuming a full frame camera; a cropped frame camera will require a 16mm lens).
What exposure will be best will depend on the level of local light pollution at your site. But from a dark site, 30 seconds at ISO 1600 and f/2.8 should work well. But without tracking, you will see some star trailing at 30 seconds. Also try shorter exposures at a higher ISO.
There’s lots of time, so take lots of shots. Include some short shots of just the Moon to blend in later, as the exposures best for picking up the Milky Way will still overexpose the Moon, even when it is darkest at mid-eclipse.
From western North America, including the landscape below will require wide lenses and a vertical format, with the Moon appearing quite small. But from a photogenic site, it might be worth the effort.
However, as my images above from the December 2010 eclipse show, if there’s any haze, the Moon could turn into a reddish blob.
You might be tempted to shoot with a long telephoto lens, but unless the camera is on a tracker, as below, the result will likely be a blurry mess. The sky moves enough during the long (over 1 second) exposures needed to pick up the reddened portion of the Moon that the image will smear when shot with long focal lengths. The solution is to use a sky tracker.
PHOTO OPTIONS 2 — CAMERA ON A TRACKER
Placing the camera on a motorized tracker that has been polar aligned to follow the motion of the stars opens up many more possibilities.
From a dark site, make use of the Moon’s position near the Milky Way to frame it and Orion and his fellow winter constellations. A 24mm lens will do the job nicely, in exposures up to 2 to 4 minutes long. But take short ones for just the Moon to layer in later.
A 50mm lens (again assuming a full frame camera) frames the Moon with the Pleiades and Hyades star clusters in Taurus.
Switching to an 85mm lens frames the clusters more tightly and makes the Moon’s disk a little larger. For me, this is the best shot to go for at this eclipse, as it tells the story of the eclipse and its unique position near the two star clusters.
But going with a longer lens allows framing the red eclipsed Moon below the blue Pleiades cluster, a fine colour contrast. A 200mm lens will do the job nicely (or a 135mm on a cropped frame camera).
Or, as I show here, the popular William Optics RedCat with its 250mm focal length will also work well. But such a lens must be on a polar-aligned tracker to get sharp shots. Use the Sidereal rate drive speed to ensure the sharpest stars over the 1 to 4 minutes needed to record lots of stars.
Take lots of exposures over a range of settings — long to bring out the deep sky detail and shorter to preserve detail in the reddened lunar disk. These can be layered and blended later in Photoshop, or in the layer-based image editing program of your choice, such as Affinity Photo or ON1 Photo RAW.
PHOTO OPTIONS 3 — THROUGH A TELESCOPE
While I think the tracked wide-field options are some of the best for this eclipse, many photographers will want frame-filling close-ups of the red Moon. While a telescope will do the job, unless it has motors to track the sky, your options are limited.
A phone clamped to the eyepiece of a telescope can capture the shrinking bright part of the eclipsed Moon as the Moon enters more deeply into the umbra. Exposures for the bright part of the Moon are short enough a motor drive on the telescope is not essential.
But if you haven’t shot the Moon with this gear before, eclipse night is not the time to learn. Practice on the Moon before the eclipse.
For shooting with a DSLR camera through a telescope you’ll need a special camera adapter nosepiece and T-ring for your camera. Again, if you don’t have the gear and the experience doing this, I would suggest not making the attempt at two in the morning on eclipse night!
For example, owners of typical beginner reflectors are often surprised to find their cameras won’t even reach focus on their telescope. Many are simply not designed for photography. Adding a Barlow lens is required for the camera to reach focus, though without a drive, exposures will be limited to short (under 1/15s) shots of the bright part of the Moon.
The challenge with this and all lunar eclipses is that the Moon presents a huge range of brightness. Short snapshots can capture the bright part of the Moon not in the umbra, but the dark umbral-shaded portion requires much longer exposures, usually over one second.
Your eye can see the whole scene (as depicted above) but the camera cannot, not in one exposure. This example is a “high dynamic range” blend of several exposures.
Plus as the eclipse progresses, longer and longer exposures are needed to capture the sequence as the Moon is engulfed by more of the umbra.
After mid-eclipse, the exposures must get progressively shorter again in reverse order. So attempting to capture an entire sequence requires a lot of exposure adjustments.
TIP: Bracket a lot! Take lots of frames at each burst of images shot every minute, or however often you wish to capture the progress of the eclipse for a final set. Unlike total solar eclipses, lunar eclipses provide lots of time to take lots of images.
PHOTO OPTIONS 4 — THROUGH A TRACKING TELESCOPE
If you want close-ups of the eclipsed red Moon, you will need to use a mount equipped with a tracking motor, such as an equatorial mount shown here. But for use with telephoto lenses and short telescopes, a polar-aligned sky tracker, as above, will work.
Exposures can now be several seconds long, and at a lower ISO speed for less noise, allowing the Moon to be captured in sharp detail and with great colour. Long exposures will even pick up stars near the Moon.
However, when shooting close-ups, use the Lunar drive rate (if your mount offers that choice) to follow the Moon itself, as it has a motion of its own against the background stars. It’s that orbital motion that takes it from west to east (right to left) through the Earth’s shadow.
Filling the camera frame with the Moon requires a surprising amount of focal length. The Moon appears big to our eyes, but is only 1/2º across.
Even with 800mm of focal length, the Moon fills only a third of a full frame camera field. Using a cropped frame camera has the advantage of tightening the field of view, but it still takes 1200mm to 1500mm of focal length to fill the frame.
But I wouldn’t worry about doing so, as longer focal lengths typically also come with slower f-ratios, requiring longer exposure times or higher ISOs, both of which can blur detail.
For close-ups, a polar-aligned equatorial mount is best. But if your telescope is a GoTo telescope on an alt-azimuth mount (such as a Schmidt-Cassegrain shown here), you should be able to get good shots.
The field of view will slowly rotate during the eclipse, making it more difficult to later accurately assemble a series of shots documenting the entire sequence.
But any one shot should be fine, though it might be best to keep exposures shorter by using a higher ISO speed. As always, take lots of shots at different settings.
You won’t be able to tell which is sharpest until you inspect them later at the computer.
TIP: People worry about exposures, but the flaw that ruins many eclipse shots is poor focus. Use Live View to focus carefully on the sharp edge of the bright part of the Moon. Or better yet, focus on a bright star nearby. Zoom up to 10x to make it easier to see when the star is in sharpest focus. It can be a good idea to refocus through the night as the changing temperature can shift the focus point of long lenses and telescopes. That might take moving the scope over to a bright star, which won’t be possible if you need to preserve the framing for a composite.
PHOTO OPTIONS 5 — HDR COMPOSITES
Using an equatorial mount tracking at the lunar rate keeps the Moon stationary. This opens up the possibility of taking a series of shots over the wide range of exposures needed to capture the Moon from bright to dark, to assemble later in processing. Take 5 to 7 shots in quick succession.
High dynamic range software can blend the images, or use luminosity masks created by extension panels for Photoshop such as Lumenzia, TK8 or Raya Pro. Either technique can create a final image that looks like what your eye saw. The key is making sure all the images are aligned. HDR software likely won’t align them for you very well.
Blending multiple exposures will also be needed to properly capture the eclipsed Moon below the Pleiades, similar to what I show here (and below) from the January 2019 eclipse when the Moon appeared near the Beehive star cluster.
PHOTO OPTIONS 6 — ECLIPSE TRACK COMPOSITES
Another popular form of eclipse image (though also one rife for laughably inaccurate fakes) is capturing the entire path of the Moon across the sky over the duration of the eclipse from start to end.
It can be done with a fixed camera on a tripod but requires a wide (14mm to 20mm) and properly framed lens, to capture the sequence as it actually appeared to proper scale, and not created by just pasting over-sized moons onto a sky to “simulate” the scene, usually badly. By the end of the day on November 19 the internet will be filled with such ugly fakes.
You could set the camera at one exposure setting (one best for when the Moon and sky are darkest at mid-eclipse) and let the camera run, shooting frames every 5 seconds or so. The result might work well as a time-lapse sequence, showing the bright sky darkening, then brightening again.
But chances are the frames taken at the start and end when the sky is lit by full moonlight will be blown out. It will still take some manual camera adjustments through the eclipse.
For a still-image composite, you should instead expose properly for the Moon’s disk at all times, a setting that will change every few minutes, then take a long exposure at mid-eclipse to pick up the stars and Milky Way. The short Moon shots are then blended into the base-layer sky image later in processing.
If the camera has been well-framed and was not moved over the 3.5 hours of the eclipse, the result is an accurate and authentic record of the Moon’s path and passage into the shadow, and not a faked atrocity!
But creating a real image requires a lot of work at the camera, and at the computer.
TIP: Shooting for composites is not work I would recommend attempting while also running other cameras. Focus on one type of image and get it right, rather than trying to do too many and doing them all poorly.
PHOTO OPTION 7 — ECLIPSE SHADOW COMPOSITE
One of the most striking types of lunar eclipse images is a close-up composite showing the Moon passing through the Earth’s umbral shadow, with the arc of the shadow edge on the Moon defining the extent of the shadow, which is about three times larger than the Moon.
Such a composite can be re-created later by placing individual exposures accurately on a wider canvas, using screen shots from planetarium software as a template guide.
But to create an image that is more accurate, it is possible to do it “in camera.” Unlike in the film days, we don’t have to do it with multiple exposures onto one piece of film.
We take lots of separate frames with a telescope or lens wide enough to contain the entire path of the Moon through the umbra. A polar-aligned equatorial mount tracking at the sidereal rate is essential. That way the scope follows the stars, not the Moon, and so the Moon travels across the frame from right to left.
Start such a sequence with the Moon at lower right if you are framing just the path through the shadow. Use planetarium software (I used Starry Night™ to create the star charts for this blog) to plan the framing for your camera, lens and site, so the Moon ends up in the middle of the frame at mid-eclipse. This is not a technique for the faint of heart!
An interesting variation would be using a 200mm to 250mm lens to frame the Moon’s shadow passage below the Pleiades, to create an image as above. That will be unique. Again, an accurately aligned tracker turning at the sidereal rate will be essential.
Acquiring the frames for any composite takes constantly adjusting the exposure during the length of eclipse, which can try your patience and gear during the wee hours of the morning.
I’ll be happy just to get a good set of images at mid-eclipse to make a single composite of the red Moon below the Pleiades.
TIP: It could be cold and lenses can frost over. A battery-powered heater coil on the optics might be essential. And spare warm batteries.
To test your equipment and your skills at focusing, you can use the waning crescent Moon in the dawn hours on the mornings of October 29 to November 2 or, after New Moon on November 4, the waxing crescent Moon on the evenings of November 6 to 10. While the crescent Moon isn’t as bright as the Full Moon, it will be a good stand in for the bright part of the eclipsed Moon when it is deep in the umbra.
Even better, the dark part of the crescent Moon lit by Earthshine is a good stand-in for the part of the Moon in the umbra. Like the eclipsed Moon, the crescent Moon’s bright and dark parts can’t be captured in one exposure. So it’s a good test for the range of exposures you’ll need for the eclipse, for practising changing settings on your camera, and for checking your tracking system.
The crescent Moon is also useful to test your manual focusing, though the sharp detail along the terminator (the line dividing the bright crescent from the earthlit dark part of the Moon) is much easier to focus on than the flat, low contrast Full Moon.
DON’T FORGET TO LOOK!
Amid all the effort needed to shoot this or any eclipse, lunar or solar, don’t forget to just look at it. No photo can ever quite capture the glowing nature of the eclipsed Moon set against the stars.
I wish you clear skies and good luck with your lunar eclipse photography. If you miss it, we have two more visible from North America next year, both total eclipses, on May 15/16 and November 8, 2022.
In an extensive technical blog, I put the Canon R6 mirrorless camera through its paces for the demands of astrophotography.
Every major camera manufacturer, with the lone exception of stalwart Pentax, has moved from producing digital lens reflex (DSLR) cameras, to digital single lens mirrorless (DSLM) cameras. The reflex mirror is gone, allowing for a more compact camera, better movie capabilities, and enhanced auto-focus functions, among other benefits.
But what about for astrophotography? I reviewed the Sony a7III and Nikon Z6 mirrorless cameras here on my blog and, except for a couple of points, found them excellent for the demands of most astrophotography.
For the last two years I’ve primarily used Canon’s astro-friendly and red-sensitive EOS Ra mirrorless, a model sadly discontinued in September 2021 after just two years on the market. I reviewed that camera in the April 2020 issue of Sky & Telescope magazine, with a quick first look here on my blog.
The superb performance of the Ra has prompted me to stay with the Canon mirrorless R system for future camera purchases. Here I test the mid-priced R6, introduced in August 2020.
NOTE: In early November 2022 Canon announced the EOS R6 MkII, which one assumes will eventually replace the original R6 once stock of that camera runs out. The MkII has a 24 Mp sensor for slightly better resolution, and offers longer battery life. But the main improvements over the R6 is to autofocus accuracy, a function of little use to astrophotographers. Only real-world testing will tell if the R6 MkII has better or worse noise levels than the R6, or has eliminated the R6’s amp glow, reported on below.
The Canon R6 has proven excellent for astrophotography, exhibiting better dynamic range and shadow recovery than most Canon DSLRs, due to the ISO invariant design of the R6 sensor. It is on par with the low-light performance of Nikon and Sony mirrorless cameras.
The preview image is sensitive enough to allow easy framing and focusing at night. The movie mode produces usable quality up to ISO 51,200, making 4K movies of auroras possible. Canon DSLRs cannot do this.
Marring the superb performance are annoying deficiencies in the design, and one flaw in the image quality – an amp glow – that particularly impacts deep-sky imaging.
The Canon R6 is superb for its:
Low noise, though not exceptionally so
ISO invariant sensor performance for good shadow recovery
Sensitive live view display with ultra-high ISO boost in Movie mode
Relatively low noise Movie mode with full frame 4K video
Low light auto focus and accurate manual focus assist
Good battery life
The Canon R6 is not so superb for its:
Lack of a top LCD screen
Bright timer display in Bulb on the rear screen
No battery level indication when shooting
Low grade R3-style remote jack, same as on entry-level Canon DSLRs
Image Quality Flaw
Magenta edge “amp glow” in long exposures
CHOOSING THE R6
Canon’s first full-frame mirrorless camera, the 30-megapixel EOS R, was introduced in late 2018 to compete with Sony. As of late-2021 the main choices in a Canon DSLM for astrophotography are either the original R, the 20-megapixel R6, the 26-megapixel Rp, or the 45-megapixel R5.
The new 24-megapixel Canon R3, while it has impressive low-noise performance, is designed primarily for high-speed sports and news photography. It is difficult to justify its $6,000 cost for astro work.
I have not tested Canon’s entry-level, but full-frame Rp. While the Rp’s image quality is likely quite good, its small battery and short lifetime on a single charge will be limiting factors for astrophotography.
Nor have I tested the higher-end R5. Friends who use the R5 for nightscape work love it, but with smaller pixels the R5 will be noisier than the R6, which lab tests at sites such as DPReview.com seem to confirm.
Meanwhile, the original EOS R, while having excellent image quality and features, is surely destined for replacement in the near future – with a Canon EOS R Mark II? The R’s successor might be a great astrophoto camera, but with the Ra gone, I feel the R6 is currently the prime choice from Canon, especially for nightscapes.
I tested an R6 purchased in June 2021 and updated in August with firmware v1.4. I’ll go through its performance and functions with astrophotography in mind. I’ve ignored praised R6 features such as eye tracking autofocus, in-body image stabilization, and high speed burst rates. They are of limited or no value for astrophotography.
Along the way, I also offer a selection of user tips, some of which are applicable to other cameras.
LIVE VIEW FOCUSING AND FRAMING
The first difference you will see when using any new mirrorless camera, compared to even a high-end DSLR, is how much brighter the “Live View” image is when shooting at night. DSLM cameras are always in Live View – even the eye-level viewfinder presents a digital image supplied by the sensor.
As such, whether on the rear screen on in the viewfinder, you see an image that closely matches the photo you are about to take, because it is the image you are about to take.
To a limit. DSLMs can do only so much to simulate what a long 30-second exposure will look like. But the R6, like many DSLMs, goes a long way in providing a preview image bright enough to frame a dark scene and focus on bright stars. Turn on Exposure Simulation to brighten the live image, and open the lens as wide as possible.
But the R6 has a trick up its sleeve for framing nightscapes. Switch the Mode dial to Movie, and set the ISO up to 204,800 (or at night just dial in Auto ISO), and with the lens wide open and shutter on 1/8 second (as above), the preview image will brighten enough to show the Milky Way and dark foreground, albeit in a noisy image. But it’s just for aiming and framing.
This is similar to the excellent, but well-hidden Bright Monitoring mode on Sony Alphas. This high-ISO Movie mode makes it a pleasure using the R6 for nightscapes. The EOS R and Ra do not have this ability. While their live view screens are good, they are not as sensitive as the R6’s, with the R and Ra’s Movie modes able to go up to only ISO 12,800. The R5 can go up to “only” ISO 51,200 in its Movie mode, good but not quite high enough for live framing on dark nights.
The R6 will also autofocus down to a claimed EV -6.5, allowing it to focus in dim light for nightscapes, a feat impossible in most cameras. In practice with the Canon RF 15-35mm lens at f/2.8, I found the R6 can’t autofocus on the actual dark landscape, but it can autofocus on bright stars and planets (provided, of course, the camera is fitted with an autofocus lens).
Autofocusing on bright stars proved very accurate. By comparison, while the Ra can autofocus on distant bright lights, it fails on bright stars or planets.
Turning on Focus Peaking makes stars turn red, yellow or blue (your choice of colours) when they are in focus, as a reassuring confirmation.
In manual focus, an additional Focus Aid overlay provides arrows that close up and turn green when in focus on a bright star or planet. Or you can zoom in by 5x or 10x to focus by eye the old way by examining the star image. I wish the R6 had a 15x or 20x magnification; 5x and 10x have long been the Canon standards. Only the Ra offered 30x for ultra-precise focusing on stars.
In all, the ease of framing and focusing will be the major improvement you’ll enjoy by moving to any mirrorless, especially if your old camera is a cropped-frame Canon Rebel or T3i! But the R6 particularly excels at ease of focusing and framing.
The key camera characteristic for astrophoto use is noise. I feel it is more important than resolution. There’s little point in having lots of fine detail if it is lost in a blizzard of high-ISO noise. And for astro work, we are almost always shooting at high ISOs.
With just 20 megapixels, low by today’s standards, the R6 has individual pixels, or more correctly “photosites,” that are each 6.6 microns in size, the “pixel pitch.”
By comparison, the 30-megapixel R (and Ra) has a pixel pitch of 5.4 microns, the 45-megapixel R5’s pixel pitch is 4.4 microns, while the acclaimed low-light champion in the camera world, the 12-megapixel Sony a7sIII, has large 8.5-micron photosites.
The bigger the photosites (i.e. the larger the pixel pitch), the more photons each photosite can collect in a given amount of time – and the more photons they can collect, period, before they overfill and clip highlights. More photons equals more signal, and therefore a better signal-to-noise ratio, while the greater “full-well depth” yields higher dynamic range.
Each generation of camera also improves the signal-to-noise ratio by suppressing noise via its sensor design and improved signal processing hardware and firmware. The R6 uses Canon’s latest DIGIC X processor shared by the company’s other mirrorless cameras.
In noise tests comparing the R6 against the Ra and Canon 6D Mark II, all three cameras showed a similar level of noise at ISO settings from 400 up to 12,800. But the 6D Mark II performed well only when properly exposed. Both the R6 and Ra performed much better for shadow recovery in underexposed scenes.
In nightscapes and deep-sky images the R6 and Ra looked nearly identical at each of their ISO settings. This was surprising considering the Ra’s smaller photosites, which perhaps attests to the low noise of the astronomical “a” model.
Or it could be that the R6 isn’t as low noise as it should be for a 20 megapixel camera. But it is as good as it gets for Canon cameras, and that’s very good indeed.
I saw no “magic ISO” setting where the R6 performed better than at other settings. Noise increased in proportion to the ISO speed. It proved perfectly usable up to ISO 6400, with ISO 12,800 acceptable for stills when necessary.
The flaw in many Canon DSLRs, one documented in my 2017 review of the 6D Mark II, was their poor dynamic range due to the lack of an ISO invariant sensor design.
The R6, as with Canon’s other R-series cameras, has largely addressed this weakness. The sensor in the R6 appears to be nicely ISO invariant and performs as well as the Sony and Nikon cameras I have used and tested, models praised for their ISO invariant behaviour.
Where this trait shows itself to advantage is on nightscapes where the starlit foreground is often dark and underexposed. Bringing out detail in the shadows in raw files requires a lot of Shadow Recovery or increasing the Exposure slider. Images from an ISO invariant sensor can withstand the brightening “in post” far better, with minimal noise increase or degradations such as a loss of contrast, added banding, or horrible discolourations.
To test the R6, I shot sets of images at the same shutter speed, one well-exposed at a high ISO, then several at successively lower ISOs to underexpose by 1 to 5 stops. I then brightened the underexposed images by increasing the Exposure in Camera Raw by the same 1 to 5 stops. In an ideal ISO invariant sensor, all the images should look the same.
The R6 did very well in images underexposed by up to 4 stops. Images underexposed by 5 stops started to fall apart, but I’ve seen that in Sony and Nikon images as well.
This behaviour applies to images underexposed by using lower ISOs than what a “normal” exposure might require. Underexposing with lower ISOs can help maintain dynamic range and avoid highlight clipping. But with nightscapes, foregrounds can often be too dark even when shot at an ISO high enough to be suitable for the sky. Foregrounds are almost always underexposed, so good shadow recovery is essential for nightscapes, and especially time-lapses, when blending in separate longer exposures for the ground is not practical.
With its improved ISO invariant sensor, the R6 will be a fine camera for nightscape and time-lapse use, which was not true of the 6D Mark II.
However, to be clear, ISO invariant behaviour doesn’t help you as much if you underexpose by using too short a shutter speed or too small a lens aperture. I tested the R6 in series of images underexposed by keeping ISO the same but decreasing the shutter speed then the aperture in one-stop increments.
The underexposed images fell apart in quality much sooner, when underexposed more than 3 stops. Again, this is behaviour similar to what I’ve seen in Sonys and Nikons. For the best image quality I feel it is always a best practice to expose well at the camera. Don’t count on saving images in post.
TIP: Underexposing by using too short an exposure time is the major mistake astrophotographers make, who then wonder why their images are riddled with odd artifacts and patten noise. Always Expose to the Right (ETTR), even with ISO invariant cameras. The best way to avoid noise is to give your sensor more signal, by using longer exposures or wider apertures. Use settings that push the histogram to the right.
LONG EXPOSURE NOISE REDUCTION
All cameras will exhibit thermal noise in long exposures, especially on warm nights. This form of noise peppers the shadows with hot pixels, often brightly coloured.
This is not the same as the shot and read noise that adds graininess to high-ISO images and that noise reduction software can smooth out. This is a common misunderstanding, even among professional photographers who should know better!
Long Exposure Noise Reduction (LENR) eliminates this thermal noise by taking a “dark frame” and subtracting it in-camera to yield a raw file free of hot pixels.
And yes, LENR does apply to raw files, another fact even many professional photographers don’t realize. It is High ISO Noise Reduction that applies only to JPGs, along with Color Space and Picture Styles.
The LENR option on the R6 did eliminate most hot pixels, though sometimes still left, or added, a few. LENR is needed more on warm nights, and with longer exposures at higher ISOs. So the extent of thermal noise in any camera can vary a lot from shoot to shoot.
When LENR is active, the R6’s rear screen lights up with “Busy,” which is annoyingly bright. To hide this display, the only option is to close the screen.
As with the EOS Ra, and all mirrorless cameras, the R6 has no “dark frame buffer” that allows several exposures to be taken in quick succession even with LENR on. Canon’s full-frame DSLRs have this little-known buffer that allows 3, 4, or 5 “light frames” to be taken in a row before the LENR dark frame kicks in a locks up the camera on Busy.
With all Canon R cameras, and most other DSLRs, turning on LENR forces the camera to take a dark frame after every light frame, doubling the time it takes to finish every exposure. That’s a price many photographers aren’t willing to pay, but on warm nights it can be necessary, and a best practice, for the reward of cleaner images.
TIP: If you find hot pixels are becoming more obvious over time, try this trick: turn on the Clean Manually routine for 30 seconds to a minute. In some cameras this can remap the hot pixels so the camera can better eliminate them.
Using LENR with the R6 did not introduce any oddities such as oddly-coloured, green or wiped-out stars. Even without LENR I saw no evidence of green stars, a flaw that plagues some Sony cameras at all times, or Nikons when using LENR.
Canons have always been known for their good star colours, and the R6 is no exception. According to DPReview the R6 has a low-pass anti-alias filter in front of its sensor. Cameras which lack such a sensor filter do produce sharper images, but stars that occupy only one or two pixels might not de-Bayer properly into the correct colours. That’s not an issue with the R6.
I also saw no “star-eating,” a flaw Nikons and Sonys have been accused of over the years, due to aggressive in-camera noise reduction even on raw files. Canons have always escaped charges of star-eating.
DSLRs are prone to vignetting along the top and bottom of the frame from shadowing by the upraised mirror and mirror box. Not having a mirror, and a sensor not deeply recessed in the body, largely eliminates this edge vignetting in mirrorless cameras.
That is certainly true of the R6. Images boosted a lot in contrast, as we do with deep-sky photos, show not the slightest trace of vignetting along the top or bottom edges There were no odd clips or metal bits intruding into the light path, unlike in the Sony a7III I tested in 2018.
The full frame of the R6 can be used without need for cropping or ad hoc edge brightening in post. Except …
EDGE ARTIFACTS/AMP GLOWS
The R6 did exhibit one serious and annoying flaw in long-exposure high-ISO images – a magenta glow along the edges, especially the right edge and lower right corner.
Whether this is the true cause or not, it looks like “amplifier glow,” an effect caused by heat from circuitry illuminating the sensor with infra-red light. It shows itself when images are boosted in contrast and brightness in processing. It’s the sort of flaw revealed only when testing for the demands of astrophotography. It was present in images I took through a telescope, so it is not IR leakage from an auto-focus lens.
I saw this type of amp glow with the Sony a7III, a flaw eventually eliminated in a firmware update that, I presume, turned off unneeded electronics in long exposures.
Amp glow is something I have not seen in Canon cameras for many years. In a premium camera like the R6 it should not be there. Period. Canon needs to fix this with a firmware update.
UPDATE AUGUST 1, 2022: As of v1.6 of the R6 firmware, released in July 2022, the amp glow issue remains and has not been fixed. It may never be at this point.
It is the R6’s only serious image flaw, but it’s surprising to see it at all. Turning on LENR eliminates the amp glow, as it should, but using LENR is not always practical, such as in time-lapses and star trails.
For deep-sky photography high-ISO images are pushed to extremes of contrast, revealing any non-uniform illumination or colour. The usual practice of taking and applying calibration dark frames should also eliminate the amp glow. But I’d rather it not be there in the first place!
The R6 I bought was a stock “off-the-shelf” model. It is Canon’s now-discontinued EOS Ra model that is (or was) “filter-modified” to record a greater level of the deep red wavelength from red nebulas in the Milky Way. Compared to the Ra, the R6 did well, but could not record the depth of nebulosity the Ra can, to be expected for a stock camera.
In wide-field images of the Milky Way, the R6 picked up a respectable level of red nebulosity, especially when shooting through a broadband light pollution reduction filter, and with careful processing.
However, when going after faint nebulas through a telescope, even the use of a narrowband filter did not help bring out the target. Indeed, attempting to correct the extreme colour shift introduced by such a filter resulted in a muddy mess and accentuated edge glows with the R6, but worked well with the Ra.
While the R6 could be modified by a third party, the edge amp glow might spoil images, as a filter modification can make a sensor even more sensitive to IR light, potentially flooding the image with unwanted glows.
TIP: Buying a used Canon Ra (if you can find one) might be one choice for a filter-modified mirrorless camera, one much cheaper than a full frame cooled CMOS camera such as a ZWO ASI2400MC. Or Spencer’s Camera sells modified versions of all the R series cameras with a choice of sensor filters. But I have not used any of their modded cameras.
A concern of prospective buyers is whether the R6’s relatively low 20-megapixel sensor will be sharp enough for their purposes. R6 images are 5472 by 3648 pixels, much less than the 8000+ pixel-wide images from high-resolution cameras like the Canon R5, Nikon Z7II or Sony a1.
Unless you sell your astrophotos as very large prints, I’d say don’t worry. In comparisons with the 30-megapixel Ra I found it difficult to see a difference in resolution between the two cameras. Stars were nearly as well resolved in the R6, and only under the highest pixel-peeping magnification did stars look a bit more pixelated in the R6 than in the Ra. Faint stars were equally well recorded.
The difference between 20 and 30 megapixels is not as great as you might think for arc-second-per-pixel plate scale. I think it would take going to the R5 with its 45 megapixel sensor to provide enough of a difference in resolution over the R6 to be obvious in nightscape scenes, or when shooting small, detailed deep-sky subjects such as globular clusters.
If landscape or wildlife photography by day is your passion, with astrophotography a secondary purpose, then the more costly but highly regarded R5 might be the better choice.
TIP: Adobe now offers (in Lightroom and in Camera Raw) a Super Resolution option, that users might think (judging by the rave reviews on-line) would be the answer to adding resolution to astro images from “low-res” cameras like the R6.
Sorry! In my tests on astrophotos I’ve found Super Resolution results unsatisfactory. Yes, stars were less pixelated, but they became oddly coloured in the AI-driven up-scaling. Green stars appeared! The sky background also became mottled and uneven.
I would not count on such “smart upscaling” options to add more pixels to astro-images from the R6. Then again, I don’t think there’s a need to.
RAW vs. cRAW
Canon now offers the option of shooting either RAW or cRAW files, the latter being the same megapixel count but compressed in file size by almost a factor of two. This allows shooting twice as many images before card space runs out, perhaps useful for shooting lots of time-lapses on extended trips away from a computer.
However, the compression is not lossless. In high-ISO test images purposely underexposed, then brightened in post, I could see a slight degradation in cRAW images – the noise background looked less uniform and exhibited a blocky look, like JPG artifacts.
TIP: With two SD card slots in the R6 (the second card can be set to record either a backup of images on card one, or serve as an overflow card) and the economy of large SD cards, there’s not the need to conserve card space as there once was. I would suggest always shooting in the full RAW format. Why accept any compression and loss of image quality?
The R6 uses a new version of Canon’s standard LP-E6 battery, the LP-E6NH, that supports charging through the USB-C port and has a higher 2130mAh capacity than the 1800mAh LP-E6 batteries. However, the R6 is compatible with older batteries.
On warm nights, I found the R6 ran fine on one battery for the 3 to 4 hours needed to shoot a time-lapse sequence, with power to spare. However, as noted below, the lack of a top LCD screen means there’s no ongoing display of battery level, a deficiency for time-lapse and deep-sky work.
For demanding applications, especially in winter, the R6 can be powered by an outboard USB power bank that has “Power Delivery” capability. That’s a handy feature. There’s no need to install a dummy battery leading out to a specialized power source.
TIP: Putting the camera into Airplane mode (to turn off WiFi and Bluetooth), turning off the viewfinder, and either switching off or closing the rear screen all helps conserve power. The R6 does not have GPS built in. Tagging images with location data requires connecting to your phone.
A major selling point for me was the R6’s low-light video capability. It replaces my Sony A7III, which had been my “go to” camera for real-time 4K movies of auroras.
As best I can tell (from the dimmer auroras I’ve shot to date), the R6 performs equally as well as the Sony. It is able to record good quality (i.e. acceptably noise-free) 4K movies at ISO 25,600 to ISO 51,200. While it can shoot at up to ISO 204,800, the excessive noise makes the top ISO an emergency-use only setting.
The R6 can shoot at a dragged shutter speed as slow as 1/8-second – good, though not as slow as the Sony’s 1/4-second slowest shutter speed in movie mode. That 1/8-second shutter speed and a fast f/1.4 to f/2 lens are the keys to shooting movies of the night sky. Only when auroras get shadow-casting bright can we shoot at the normal 1/30-second shutter speed and at lower ISOs.
As with Nikons (but not Sonys), the Canon R6 saves its movie settings separately from its still settings. When switching to Movie mode you don’t have to re-adjust the ISO, for example, to set it higher than it might have been for stills, very handy for taking both stills and movies of an active aurora, where quick switching is often required.
Unlike the R and Rp, the R6 captures 4K movies from the full width of the sensor, preserving the field of view of wide-angle lenses. This is excellent for aurora shooting.
However, the R6 offers the option of a “Movie Crop” mode. Rather than taking the 4K movie downsampled from the entire sensor, this crop mode records from a central 1:1 sampled area of the sensor. That mode can be useful for high-magnification lunar and planetary imaging, for ensuring no loss of resolution. It worked well, producing videos with less pixelated fine details in test movies of the Moon.
Though of course I have yet to test it on one, the R6 should be excellent for movies of total solar eclipses. It can shoot 4K up to 60 frames per second in both full frame and cropped frame. It cannot shoot 6K (buy the R3!) or 8K (buy the R5!).
Shooting in the R6’s Canon cLog3 profile records internally in 10-bit, preserving more dynamic range in movies, up to 12 stops. During eclipses, that will be a benefit for recording totality, with the vast range of brightness in the Sun’s corona. It should also aid in shooting auroras which can vary over a huge range in brightness.
TIP: Processing cLog movies, which look flat out of camera, requires applying a cLog3 Look Up Table, or LUT, to the movie clips in editing, a step called “colour grading.” This is available from Canon, from third-party vendors or, as it was with my copy of Final Cut Pro, might be already installed in your video editing software. When shooting, turn on View Assist so the preview looks close to what the final graded movie will look like.
EXPOSURE TRACKING IN TIME-LAPSES
In one test, I shot a time-lapse from twilight to darkness with the R6 in Aperture Priority auto-exposure mode, of a fading display of noctilucent clouds. I just let the camera lengthen the shutter speed on its own. It tracked the darkening sky very well, right down to the camera’s maximum exposure time of 30 seconds, using a fish-eye lens at f/2.8. This demonstrated that the light meter in the R6 was sensitive enough to work well in dim light.
Other cameras I have used cannot do this. The meter fails at some point and the exposure stalls at 5 or 6 seconds long, resulting in most frames after that being underexposed. By contrast, the R6 showed excellent performance, negating the need for special bulb ramping intervalometers for some “holy grail” scenes. Here’s the resulting movie.
In addition, the R6’s exposure meter tracked the darkening sky superbly, with nary a flicker or variation. Again, few cameras can do this. Nikons have an Exposure Smoothing option in their Interval Timers which works well.
The R6 has no such option but doesn’t seem to need it. The exposure did fail at the very end, when the shutter reached its maximum of 30 seconds. If I had the camera on Auto ISO, it might have started to ramp up the ISO to compensate, a test I have yet to try. Even so, this is impressive time-lapse performance in auto-exposure.
The R6, like the low-end Rp, lacks a top LCD screen for display of camera settings and battery level. In its place we get a traditional Mode dial, which some daytime photographers will prefer. But for astrophotography, a backlit top LCD screen provides useful information during long exposures.
Without it, the R6 provides no indication of battery level while a shoot is in progress, for example, during a time-lapse. A top screen is also useful for checking ISO and other settings by looking down at the camera, as is usually the case when it’s on a tripod or telescope.
The lack of a top screen is an inconvenience for astrophotography. We are forced to rely on looking at the brighter rear screen for all information. It is a flip-out screen, so can be angled up for convenient viewing on a telescope.
The R6 has a remote shutter port for an external intervalometer, or control via a time-lapse motion controller. That’s good!
However, the port is Canon’s low-grade 2.5mm jack. It works, and is a standard connector, but is not as sturdy as the three-pronged N3-style jack used on Canon’s 5D and 6D DSLRs, and on the R3 and R5. Considering the cost of the R6, I would have expected a better, more durable port. The On/Off switch also seems a bit flimsy and easily breakable under hard use.
These deficiencies provide the impression of Canon unnecessarily “cheaping out” on the R6. You can forgive them with the Rp, but not with a semi-professional camera like the R6.
Unlike the Canon R and Ra (which still mysteriously lack a built-in interval timer, despite firmware updates), the R6 has one in its firmware. Hurray! This can be used to set up a time-lapse sequence, but on exposures only up to the maximum of 30 seconds allowed by the camera’s shutter speed settings, true of most in-camera intervalometers.
For 30-second exposures taken in succession as quickly as possible the interval on the R6 has to be set to 34 seconds. The reason is that the 30-second exposure is actually 32 seconds, true of all cameras. With the R6, having a minimum gap in time between shots requires an Interval not of 33 seconds as with some cameras, but 34 seconds. Until you realize this, setting the intervalometer correctly can be confusing.
Like all Canon cameras, the R6 can be set to take only up to 99 frames, not 999. That seems a dumb deficiency. Almost all time-lapse sequences require at least 200 to 300 frames. What could it possibly take in the firmware to add an extra digit to the menu box? It’s there at in the Time-lapse Movie function that assembles a movie in camera, but not here where the camera shoots and saves individual frames. It’s another example where you just can’t fathom Canon’s software decisions.
TIP: If you want to shoot 100 or more frames, set the Number of Frames to 00, so it will shoot until you tell the camera to stop. But awkwardly, Canon says the way to stop an interval shoot is to turn off the camera! That’s crude, as doing so can force you to refocus if you are using a Canon RF lens. Switching the Mode dial to Bulb will stop an interval shoot, an undocumented feature.
As with most recent Canon DSLRs and DSLMs, the menu also includes a Bulb Timer. This allows setting an exposure of any length (many minutes or hours) when the camera is in Bulb mode. This is handy for single long shots at night.
However, it cannot be used in conjunction with the Interval Timer to program a series of multi-minute exposures, a pity. Instead, a separate outboard intervalometer has to be used for taking an automatic set of any exposures longer than 30 seconds, true of all Canons.
In Bulb and Bulb Timer mode, the R6’s rear screen lights up with a bright Timer readout. While the information is useful, the display is too bright at night and cannot be dimmed, nor turned red for night use, exactly when you are likely to use Bulb. The power-saving Eco mode has no effect on this display, precisely when you would want it to dim or turn off displays to prolong battery life, another odd deficiency in Canon’s firmware.
The Timer display can only be turned off by closing the flip-out screen, but now the viewfinder activates with the same display. Either way, a display is on draining power during long exposures. And the Timer readout lacks any indication of battery level, a vital piece of information during long shoots. The Canon R, R3 and R5, with their top LCD screens, do not have this annoying “feature.”
TIP: End a Bulb Timer shoot prematurely by hitting the Shutter button. That feature is documented.
IN-CAMERA IMAGE STACKING
The R6 offers a menu option present on many recent Canon cameras: Multiple Exposure. The camera can take and internally stack up to 9 images, stacking them by using either Average (best for reducing noise) or Bright mode (best for star trails). An Additive mode also works for star trails, but stacking 9 images requires reducing the exposure of each image by 3 stops, say from ISO 1600 to ISO 200, as I did in the example below.