Testing Noise Reduction Programs for Astrophotography


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! 


TL;DR SUMMARY

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[See below for comments on the newer DxO PureRaw3, which suffers from the same issues.]

The three test images in Adobe Camera Raw showing the Basic settings applied.

METHODOLOGY

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. 


THE CONTENDERS

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.

[See below for an April 2023 update with a comparison of Adobe’s new AI Denoise with DxO DeepPrimeXD and Topaz PhotoAI.]

The new smart AI programs should improve upon this. But do they?

PLEASE NOTE: 

  • 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 NoNoise 2023’s control interface.

ON1 NoNoise AI 2023

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.

Version tested: 17.0.1

Topaz DeNoise AI’s four-pane view to select the best AI model.

Topaz DeNoise AI 

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.

Version tested: 3.7.0

Topaz Photo AI’s control interface for its three main functions: noise, sharpening and upscaling.

Topaz Photo AI

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. [See below for a test of PhotoAI v1.3.1, current as of April 2023.]

Version tested: 1.0.9

Luminar Neo’s Edit interface with choices of many filters and effects, including Noiseless AI.

Luminar Neo Noiseless AI

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. 

Version tested: 1.5.0

DxO PureRAW’s simple interface with few choices for Noise Reduction settings.

DxO PureRAW2

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. [See below for a test of DeepPrimeXD, now offered with PureRaw3.]

Version tested: 2.2

Noise Terminator’s controls allow adjusting strength and detail.

RC-Astro NoiseXTerminator

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 


NIGHTSCAPE TEST

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. 

The test results on a sample nightscape.
  • 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, though as of April 2023 its performance on landscapes has improved but is not ideal. 


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. 

The test results on a sample wide-field deep-sky image.
  • 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.
ON1 NoNoise “High Detail” option ruins star fields, as shown at right. Use “Original” instead.
  • 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 PureRAW2 did 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. 

The test results on a sample deep-sky close-up.
  • 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. 
Comparing DeNoise’s and Photo AI’s different model settings.

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. 

[UPDATE MARCH 2023: DxO has indeed brought out PureRaw3 as a paid upgrade that, as expected, offers the DeepPrimeXD. In testing the new version I found that, while it did not seem to alter an image’s exposure as PureRaw2 did, DeepPrime and DeepPrimeXD still unacceptably ruin starry skies, by either adding a fine-scale mosaic effect (DeepPrime) or weird wormy artifacts (DeepPrimeXD). Try it for yourself to see if you find the same.]

Comparing DxO’s various Prime model settings. DeepPrimeXD is only in PhotoLab 6.
  • 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.

APRIL 2023 UPDATE — TESTING ADOBE’S NEW AI Denoise

In April 2023 Adobe updated Lightroom Classic to v12.3 and the Camera Raw plug-in for Bridge and Photoshop to 15.3. The major new feature was a long-awaited AI noise reduction from Adobe called Denoise. It works only on raw files and generates a new raw DNG file to which all the raw develop settings, including AI masks, can be applied. But the DNG file is some four times larger than the original raw file from the camera.

Here’s a comparison of Camera Raw using the old noise reduction and the new AI option, with DxO’s DeepPrimeXD and Topaz’s PhotoAI, on an aurora image from April 23, 2023:

I used Topaz Photo AI as that’s the program Topaz is now putting all their development effort into, neglecting their other plug-ins such as DeNoise AI. I used DxO PhotoLab 6 with its DeepPrimeXD option to export a DNG with only noise reduction applied, for results identical to what is now offered with DxO’s separate PureRaw3 plug-in.

At 100% above, there’s very little obvious difference. They show up when pixel peeping.

400% blow-ups of the sky – Tap or click to download a full-res JPG

Above are 400% blow-ups of a section of the sky.

Compared to using Adobe’s old noise reduction sliders, their new AI Denoise did a far superior job at smoothing noise, and providing sharpening – almost too much, making even the smallest stars pop out more, perhaps a good thing. But there’s no control of that sharpening.

DxO’s DeepPrimeXD provides a similar, or perhaps more excessive level of AI sharpening. While it smooths noise, it introduces all manner of wormy AI artifacts. It is unacceptable.

Topaz PhotoAI’s noise reduction and sharpening, here both applied with their AutoPilot settings, smoothed noise, but created a patchy appearance. It also softened the stars, despite having sharpening turned on. It was the worst of the set.

400% blow-ups of a section of the ground y – Tap or click to download a full-res JPG

In a similar set of blow-ups of the ground, the old Adobe noise reduction did just that — it smoothed only some noise. The new AI Denoise not only smooths noise, it also applies AI-based sharpening, to the point of almost inventing detail. Here it looks believable, but in other tests I have seen it add content, such as structures in the aurora, that looked fake and out of place. Or just plain wrong!

DxO’s DeepPrimeXD’s main feature over the older DeepPrime is the “eXtra Detail” it finds. Here it produces a result similar to Adobe Denoise, though in some areas of this and other images, I find it is over-sharpening. As with Adobe, there is no option for backing off the sharpening. Other than using DeepPrime or Prime noise reduction.

Topaz PhotoAI didn’t do much to add sharpening. If anything, it made the image softer. While PhotoAI has improved with its weekly updates, it still falls far short of the competition, at least for astrophotos and nightscapes.

The bottom line — Adobe’s new AI Denoise can do a superb job on astrophotos, and will be particularly useful for high-ISO nightscapes, perhaps better than any of the competition. But watch what it does! It can invent details or create results that look artificial. Being able to adjust the sharpening would be helpful. Perhaps that will come in an update.


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: 

Nik Dfine2’s control interface.
  • Dfine2, included with the Nik Collection of plug-ins sold by DxO (shown above), and
  • Reduce Noise v9 sold by Neat Image (shown below). 
Neat Image’s Reduce Noise control interface – the simple panel.

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. 

Comparing results with Neat Image and Nik Dfine2 on the nightscape test image.

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. 

Comparing results with Neat Image and Nik Dfine2 on the wide-field test image.

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. 

Comparing results with Neat Image and Nik Dfine2 on the deep-sky test image.

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?

As noted above, with v15.3 of Camera Raw and v12.3 of Lightroom Classic, Adobe finally introduced their contender into the AI noise reduction contest. And it is a very good entry at that.

But it works only on raw files early in the workflow, and it generates a new raw DNG file, one four times the size of the original. The suggestion is that this technology will expand so that the AI noise reduction can be applied later in the workflow to other file formats.

Indeed, in the last couple of years Adobe has introduced several amazing and powerful “Neural Filters” into Photoshop, which work wonders with one click.

Neural network Noise Reduction is coming to Photoshop. One day!

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, as a version of the AI noise reduction now offered in Lightroom and Camera Raw.

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. 

— Alan, November 15, 2022 / Revised April 27, 2023 / AmazingSky.com  

Testing the Canon R5 for Astrophotography


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! 

All images are © 2022 by Alan Dyer/AmazingSky.com. Use without permission is prohibited.


The Canon R5 uses a full-frame sensor offering 45 megapixels, producing images with 8192 x 5464 pixels, and making 8K video possible.

TL;DR Summary

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. 

This is a stack of 12 x 5-minute exposures with a Sharpstar 94EDPH refractor at f/4.5 and the Canon R5 at ISO 800, taken as a test of the R5 for deep-sky imaging. No filters were employed. Close-ups of sub-frames from this shoot with the R5, and also with the R6 and Ra, are used throughout the review.

R5 Pros

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

R5 Cons

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
  • High cost! 

The flip-out screen of the R5 (and all recent Canon cameras) requires an L-bracket with a notch in the side (a Small Rig unit is shown here) to accommodate the tilting screen.  

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

This compares the back-of-camera views of the R5 vs. the R6, with both set to their highest ISO in Movie mode for the brightest preview image.

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

As with other Canon mirrorless cameras, the R5 offers a Focus Assist overlay (top) to aid manual focusing. It works on bright stars. It also has a 6x and 15x magnifications for even more precise 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. 

Turning on Focus Guide provides the arrowed overlays shown above.

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. 

This compares the noise on a dark nightscape at the typical ISOs used for such scenes. A level of noise reduction shown has been applied in Camera Raw. 

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. 

This compares the R5 to the R6 and Ra cameras at the high ISOs of 3200 and 6400 often used for Milky Way nightscapes. 

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. 

This compares the R5 to the R6 and Ra cameras at the more moderate ISOs of 800 and 1600 used for brighter nightscapes. 

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

This compares the R5 at the typical ISO settings used for deep-sky imaging, with no noise reduction applied to the raw files for this set. The inset shows the portion of the frame contained in the blow-ups.

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.  

This compares the R5 to the R6 and Ra cameras at ISO 6400, higher than typically used for deep-sky imaging. No noise reduction was applied to the raw files.

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.

This compares the R5 to the R6 and Ra cameras at the lower ISOs of 800 and 1600 best for deep-sky imaging, for better dynamic range. No noise reduction was applied to the raw files. 

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. 


ISO INVARIANCY

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. 

This shows the same scene with the R5 progressively underexposed by shooting at a lower ISO then boosted in exposure in Adobe Camera Raw.

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. 


THERMAL NOISE

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. 

Thermal noise is more insidious and harder to eliminate in processing without harming the image. However, Monika Deviat offers a clever method here at her website

This shows a long-exposure nightscape scene both without and with Long Exposure Noise Reduction turned on. LENR eliminated most, though not all, of the hot pixels in the shadows. 

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.

This compares a long exposure of nothing (with the lens cap on), both without LENR (left) and with LENR (right), to show the extent of just the thermal noise.

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.

Long Exposure Noise Reduction is useful when the gap in time between exposures it produces is not critical.

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. 


STAR QUALITY 

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. 

This is a single developed raw frame from the stack of four minute exposures used to create the final image shown at the top. It shows sharp and nicely coloured stars, with no odd green stars. 

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. 


RED SENSITIVITY 

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.  

This compares identically processed four-minute exposures at ISO 800 with the R5 vs. the red-sensitive Ra. 

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!)

This compares identically processed four-minute exposures at ISO 800 with the R5 vs. the red-sensitive Ra. 

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

This compares blow-ups of images of the Moon taken through a 5-inch f/6 refractor (780mm focal length) with the R6 and R5. 

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

This compares extreme blow-ups of images of the North America Nebula used for the other tests, shot with a 94mm f/4.5 refractor with the three cameras.

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. 

This is dim green Comet PanSTARRS C/2017 K2, at top, passing above the star clusters IC 4756 at lower left and NGC 6633 at lower right on May 25-26, 2022. This is a stack of ten 5-minute exposures with a William Optics RedCat 51 at f/4.9 and the Canon R5 at ISO 800. 

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?

This compares an original R6 image with the same image rescaled 200% in ON1 Resize AI and Topaz Gigapixel AI, and with those three compared to an original R5 image. 

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. 


VIDEO Resolution 

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. 

The R5 offers the options of 8K and 4K movies each in either the wider DCI Digital Cinema standard (8K-D and 4K-D) or more common Ultra-High Definition standard (8K-U and 4K-U), as well as conventional 1080 HD.
This shows the Moon shot with the same 460mm-focal length telescope, with full-width frame grabs from movies shot in 8K, 4K, and 4K Movie Crop modes.

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. 

This compares close-ups of frame grabs of the Moon movies shown in full-frame above, as well as a frame from an R6 movie, to compare resolutions.

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.

This compares the R5 at 8K with it in the best quality 4K Fine HQ vs. the R5 and R6 in their 4K Movie Crop modes.

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.


Canon CLOG3

This shows the difference (using frame grabs from 4K movies) between shooting in Canon C-Log3 and shooting with normal “in-camera” colour grading. The exposures were the same. 

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.


LOw-Light VIDEO 

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. 

This compares frame grabs of aurora movies shot the same night with the R5 at 8K and 4K with the Canon R6 at 4K, all at ISO 51,200.

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.

Like the R6, the R5 comes with a new version of Canon’s standard LP-E6 battery, the LP-E6NH. 

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.


OVERHEATING

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. 

The R5’s Canon-standard flip screen

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’s top-mounted backlit LCD screen

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 front-mounted N3-style remote port

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.

The R5’s back panel buttons and controls

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.

The R5’s twin cards, a CFexpress Type B and an SD UHS-II 

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.

Allocating memory card use

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. 


FIRMWARE FEATURES

Setting the Interval Timer

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.

Setting the Bulb Timer

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. 

Custom button functions

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. 

Assigning Audio Memos to the Rate button

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. 

The infamous Release Shutter Without Lens command

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! 

OTHER FEATURES

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

Multi-segment panoramas with the R5, like this aurora scene, yield superb resolution but can become massive in size, pressing the ability of software and hardware to process them. 

CONCLUSION

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! 

— Alan, June 23, 2022 / © 2022 Alan Dyer / AmazingSky.com  


Shooting with Canon’s EOS Ra Camera


IC 1805 in Cassiopeia (Traveler and EOS Ra)

I had the chance to test out an early sample of Canon’s new EOS Ra camera designed for deep-sky photography. 

Once every 7 years astrophotographers have reason to celebrate when Canon introduces one of their “a” cameras, astronomical variants optimized for deep-sky objects, notably red nebulas.

In 2005 Canon introduced the ground-breaking 8-megapixel 20Da, the first DLSR to feature Live View for focusing. Seven years later, in 2012, Canon released the 18-megapixel 60Da, a camera I still use and love.

Both cameras were cropped-frame DSLRs.

Now in 2019, seven years after the 60Da, we have the newly-released EOS Ra, the astrophoto version of the 30-megapixel EOS R released in late 2018. The EOS R is a full-frame mirrorless camera with a sensor similar to what’s in Canon’s 5D MkIV DSLR.

Here, I present a selection of sample images taken with the new EOS Ra.

Details on its performance is at my “first-look” review at Sky and Telescope magazine’s website.

IC 1805 in Cassiopeia (Traveler and EOS Ra)
The large emission nebula IC 1805 in Cassiopeia, aka the Heart Nebula. The round nebula at top right is NGC 896. The large loose star cluster at centre is Mel 15; the star cluster at left is NGC 1027. The small cluster below NGC 896 is Tombaugh 4. This is a stack of 8 x 6-minute exposures with the Canon EOS Ra mirrorless camera at ISO 1600 through the Astro-Physics Traveler apo refractor at f/6 with the Hotech field flattener. Stacked, aligned and processed in Photoshop.

Both versions of the EOS R have identical functions and menus.

The big difference is that the EOS Ra, as did Canon’s earlier “a” models, has a factory-installed filter in front of the sensor that transmits more of the deep red “hydrogen-alpha” wavelength emitted by glowing nebulas.

Normal cameras suppress much of this deep-red light as a by-product of their filters cutting out the infra-red light that digital sensors are very sensitive to, but that would not focus well.

NGC 7000 North America Nebula (105mm Apo & Canon EOS Ra)
The North America Nebula, NGC 7000, in Cygnus, taken with the new Canon EOS Ra factory-modified “astronomical” version of the Canon EOS R mirrorless camera. This is a stack of 4 x 6-minute exposures, with LENR on and at ISO 1600, through the Astro-Physics Traveler 105mm f/6 apo refractor with the Hutech field flattener.

I was sent an early sample of the EOS Ra, and earlier this autumn also had a sample of the stock EOS R.

Both were sent for testing so I could prepare a test report for Sky and Telescope magazine. The full test report will appear in an upcoming issue.

IC 1396 in Cepheus (Traveler and EOS Ra)
The large emission nebula IC 1396 in Cepheus with the orange “Garnet Star” at top, and the Elephant Trunk Nebula, van den Bergh 142, at bottom as a dark lane protruding into the emission nebula. This is a stack of 5 x 6-minute exposures with the Canon EOS Ra mirrorless camera at ISO 1600 through the Astro-Physics Traveler apo refractor at f/6 with the Hotech field flattener. Stacked, aligned and processed in Photoshop.

But my “first-look” review can be found here on the Sky and Telescope website.

Please click thru for comments on:

• How the Ra compares to previous “a” models and third-party filter-modified cameras

• How the Ra works for normal daylight photography

• Noise levels compared to other cameras

• Features unique to the EOS Ra, such as 30x Live View focusing

Messier 52 and the Bubble Nebula (Traveler and EOS Ra)
Messier 52 open cluster, at left, and the Bubble Nebula, NGC 7635 below and to the right of it, at centre, plus the small red nebula NGC 7538 at right. The open cluster at lower right is NGC 7510. All in Cassiopeia. This is a stack of 8 x 6-minute exposures at ISO 1600 with the Canon EOS Ra camera and Astro-Physics Traveler apo refractor at f/6 with the Hotech field flattener. No LENR dark frame subtraction employed as the temperature was -15° C.


UPDATE — November 25, 2019

As part of further testing I shot the Heart and Soul Nebulas in Cassiopeia through my little Borg 77mm f/4 astrograph with both the EOS Ra and my filter-modified 5D MkII (modified years ago by AstroHutech) to compare which pulled in more nebulosity. It looked like a draw.

Both images are single 8-minute exposures, taken minutes apart and developed identically in Adobe Camera Raw, but adjusted for colour balance to equally neutralize the sky background. The histograms look similar. Even so, the Ra looks a little redder overall. But keep in mind a sky or nebula can be made to appear any shade of red you like in processing.

The question is which camera shows more faint nebulosity?

The modified 5D MkII has always been my favourite camera for this type of astrophotography, picking up more nebulosity than other “a” models I’ve tested, including the Nikon D810a.

But in this case, I’d say the EOS Ra is performing as well as, if not better than the 5D MkII. How well any third-party modified camera you buy now performs will depend which, if any, filter the modifier installs in front of the sensor. So your mileage will vary.

EOS Ra and 5D MkII Comparison


For most of my other testing I shot through my much-prized Astro-Physics Traveler, a 105mm aperture f/6 apochromatic refractor on the Astro-Physics Mach1 mount.

To connect the EOS Ra (with its new RF lens mount) to my existing telescope-to-camera adapter and field flattener lens I used one of Canon’s EF-EOS R lens adapters.

EOS Ra on Scope

EOS Ra on Scope CU

The bottom line is that the EOS Ra works great!

It performs very well on H-alpha-rich nebulas and has very low noise. It will be well-suited to not only deep-sky photography but also to wide-field nightscape and time-lapse photography, perhaps as Canon’s best camera yet for those applications.

EOS Ra Front View-Face On

WHAT ABOUT THE PRICE?

The EOS Ra will sell for $2,500 US, a $700 premium over the cost of the stock EOS R. Some complain. Of course, if you don’t like it, you don’t have to buy it. This is not an upgrade being forced upon you.

As I look at it, it is all relative. When Nikon’s astronomy DSLR, the 36 Mp D810a, came out in 2015 it sold for $3,800 US, $1,300 more than the EOS Ra. It was, and remains a fine camera, if you can find one. It is discontinued.

A 36 Mp cooled and dedicated CMOS astro camera, the QHY367, with the same chip as the D810a, goes for $4,400, $1,900 more than the Ra. Yes, it will produce better images I’m sure than the EOS Ra, but deep-sky imaging is all it can do. At a cost, in dollars and ease of use.

And yes, buying a stock EOS R and having it modified by a third party costs less, and you’ll certainly get a good camera, for $300 to $400 less than an Ra. But …

• The EOS Ra has a factory adjusted white balance for ease of “normal” use — no need to buy correction filters. So there’s a $$ saving there, even if you can find clip-in correction filters for the EOS R — you can’t.

• And the Ra retains the sensor dust cleaning function. Camera modifier companies remove it or charge more to reinstall it.

• And the 30x live view magnification is very nice.

• The EOS Ra also carries a full factory warranty.

Do I wish the EOS Ra had some other key features? Sure. A mode to turn all menus red would be nice. As would an intervalometer built-in, one that works with the Bulb Timer to allow sequences of programmed multi-minute exposures. Both could be added in with a firmware update.

And providing a basic EF-EOS R lens adapter in the price would be a welcome plus, as one is essential to use the EOS Ra on a telescope.

That’s my take on it. I’ll be buying one. But then again I bought the 20Da, twice!, and the 60Da, and I hate to think what I paid for those much less capable cameras.

Canon EOS Ra and 15-35mm

BONUS TEST — The RF 15-35mm L Lens

Canon is also releasing an impressive series of top-class RF lenses for their R mirrorless cameras. The image below is an example astrophoto with the new RF 15-35mm f/2.8 L zoom lens, an ideal combination of focal lengths and speed for nightscape shooting.

Orion and Winter Stars Rising
Orion and the winter stars rising on a late October night, with Sirius just clearing the horizon at centre bottom, Capella and the Pleiades are at top. M44 cluster is at far left. Taken with the Canon 15-35mm RF lens at 15mm and f/2.8 and the EOS Ra camera at ISO 800 as part of testing. A stack of 4 x 2-minute exposures on the Star Adventurer tracker.

Below is a further set of stacked and processed images with the RF 15-35mm L lens, taken in quick succession, at 15mm, 24mm, and 35mm focal lengths, all shot wide open at f/2.8. The EOS Ra was on the Star Adventurer tracker (as below) to follow the stars.

EOS Ra on Star Adventurer

Click or tap on the images below to view a full-resolution version for closer inspection.

Autumn Milky Way (15-35mm RF at 15mm + EOS Ra).jpg
15mm — Northern autumn Milky Way with RF 15-35mm at f/2.8 and at 15mm focal length. Taken with the EOS Ra at ISO 800 for a stack of 4 x 2-minute exposures.

Autumn Milky Way (15-35mm RF at 24mm + EOS Ra).jpg
24mm — Northern autumn Milky Way with RF 15-35mm at f/2.8 and at 24mm focal length. Taken with the EOS Ra at ISO 800 for a stack of 2 x 2-minute exposures.

Autumn Milky Way (15-35mm RF at 35mm + EOS Ra).jpg
35mm — Northern autumn Milky Way with RF 15-35mm at f/2.8 and at 35mm focal length. Taken with the EOS Ra at ISO 800 for a stack of 2 x 2-minute exposures.

The RF 15-35mm lens performs extremely well at 15mm exhibiting very little off-axis aberrations at the corners.

Off-axis aberrations do increase at the longer focal lengths but are still very well controlled, and are much less than I’ve seen on my older zoom and prime lenses in this focal length range.

The RF 15-35mm is a great complement to the EOS Ra for wide-field Milky Way images.

I was impressed with the new EOS Ra. It performs superbly for astrophotography.

Again, click through to Sky and Telescope for “first look” details on the test results.

— Alan, November 6, 2019 / UPDATED Nov 25, 2019 / © 2019 AmazingSky.com 

 

Touring the Wonders of the Winter Sky


The Wonders of the Winter Sky

I present a tour of the deep-sky wonders of the winter sky.

While some might think the Milky Way is only a summer sight, the winter Milky Way is well worth a look!

In January and February we are looking outward from our location in the Milky Way, toward the Orion Spur, the minor spiral arm we live in. In it, and in the major Perseus Arm that lies beyond, lie hotbeds of star formation.

Artist's impression of the Milky Way (updated - annotated)
Courtesy European Southern Observatory

These star forming areas create a panorama of star clusters and glowing nebulas along the winter Milky Way and surrounding the constellation of Orion. The montage above shows the best of the deep-sky sights at this time or year.

(And yes, for southern hemisphere viewers I know this is your summer sky! But for us northerners, Orion is forever associated with frosty winter nights.)

The closeups below are all with a 200mm telephoto lens providing a field of view similar to that of binoculars. However, most of these nebulas are photographic targets only.


The Belt and Sword of Orion

The Belt and Sword of Orion with Barnard's Loop
This is a stack of 16 x 2- to 3-minute exposures with the filter-modified Canon 5D MkII at ISO 800 to 1250 and 200mm Canon L-Series lens at f/2.8. Taken with the Fornax Lightrack tracker as part of testing. Taken from home on January 8, 2019 during a clear couple of hours between passing haze and cloud.

This is the heart of the star formation activity, in the centre of Orion.

The bright Orion Nebula (or Messier 42 and 43) at bottom in Orion’s Sword is obvious in binoculars and glorious in a small telescope.

The Horsehead Nebula above centre and just below Orion’s Belt is famous but is a tough target to see through even a large telescope.

Barnard’s Loop at left is a wave of nebulosity being blown out of the Orion area by strong stellar winds. Any sighting of this object by eye is considered a feat of observing skill!


The Rosette Nebula and Area

Rosette and Christmas Tree Cluster with 200mm
The area of the Rosette Nebula (bottom) and Christmas Tree Cluster (top) in Monoceros with the Fornax Lightrack tracker and 200mm lens and filter modified Canon 5D MkII. This is a stack of 10 x 3 minute exposures at ISO 800.

The small cluster of hot young stars inside the Rosette Nebula is blowing a hole in the nebula giving it its Rosette name. Above is a loose star cluster called the Christmas Tree, surrounded by more faint nebulosity that includes the tiny Cone Nebula.


Gemini Clusters and Nebulas

The Clusters and Nebulas of Gemini
This is a stack of 10 x 3-minute exposures with the filter-modified Canon 5D MkII at ISO 800 and 200mm Canon L-Series lens at f/2.8. Some light haze passing through in some exposures added the natural star glows. I left those in as part of the stack to add the glows. Taken with the Fornax Lightrack tracker as part of testing. Taken from home on a rare fine and mild winter night, January 4, 2019.

This field of clusters and nebulosity is above Orion in Gemini, with Messier 35 the main open star cluster here at top. Below M35 is the tiny star cluster NGC 2158. The nebulosity at left between Mu and Eta Geminorum is IC 443, a remnant of a supernova explosion, and is aka the Jellyfish Nebula. The nebula at bottom is IC 2174, just over the border in Orion and aka the Monkeyhead Nebula.


Auriga Clusters and Nebulas

The Clusters and Nebulas of Auriga
This is a stack of 5 x 3-minute exposures with the filter-modified Canon 5D MkII at ISO 800 and 200mm Canon L-Series lens at f/2.8. Taken with the Fornax Lightrack tracker as part of testing. Diffraction spikes added with Astronomy Tools actions. Taken from home on January 4, 2019.

Above Gemini and Orion lies Auriga, with its rich field of clusters and nebulosity, with — from left to right — Messier 37, Messier 36, and Messier 38, as the main open star clusters here. Below M38 is NGC 1907. The nebulosity at right is IC 410 and IC 405, the Flaming Star Nebula.

In between them is the colourful asterism known as the Little Fish. Messier 38 is also known as the Starfish Cluster while Messier 36 is called the Pinwheel Cluster. The bright red nebula at top is Sharpless 2-235. The little nebulas at centre are NGC 1931 and IC 417.


The California Nebula

The California Nebula in Perseus
This is a stack of 5 x 3-minute exposures with the filter-modified Canon 5D MkII at ISO 800 and 200mm Canon L-Series lens at f/2.8. An additional exposure taken through the Kenko Softon A filter is layered in to add the star glows to bring out their colours. Taken with the Fornax Lightrack tracker. Taken from home on a rare fine and mild winter night, January 4, 2019.

Now we enter Perseus, more an autumn constellation but well up through most of the winter months. It contains the aptly named California Nebula, NGC 1499, at top left, with the bright star Zeta Persei. at bottom A small region of reflection nebulosity, IC 348, surrounds the star Atik, or Omicron Persei, at bottom right. The star just below NGC 1499 is Menkib, or Xi Persei, and is likely energizing the nebula.


The Pleiades, or Seven Sisters

Pleiades M45 with 200mm Lens
The Pleiades with the Fornax Lightrack tracker and 200mm lens + Canon 5D MkII in a stack of 10 x 3 minute exposures at ISO 800.

Obvious to the eye and central to the sky lore of many cultures is the Pleiades, aka the Seven Sisters, in Taurus the bull. It is also called Messier 45.

This is a newly formed cluster of hundreds of stars, passing through a dusty region of the Milky Way, which adds the fuzzy glows around the stars — an example of a reflection nebula, glowing blue as it reflects the blue light of the young stars.


The Hyades

The Hyades Star Cluster with NGC 1647 in Taurus
This is a stack of 5 x 2-minute exposures with the Canon 5D MkII at ISO 800 and 200mm Canon L-Series lens at f/2.8. An additional exposure taken through the Kenko Softon A filter is layered in to add the star glows to bring out their colours. Taken with the Fornax Lightrack tracker. Diffraction spikes added with Astronomy Tools actions for artistic effect.

Below the Pleiades in Taurus lies the larger Hyades star cluster. The V-shaped cluster stars are all moving together and lie about 150 light years away. Bright yellow Aldebaran, the eye of Taurus, is an intruder and lies at only half that distance, so is not a member of Hyades but is a more nearby star. The smaller, more distant star cluster NGC 1647 appears at left.


Seagull Nebula

Seagull Nebula and Sirius with 200mm
This is a stack of 10 x 3 minute exposures at ISO 800 (with the filter-modified Canon 5D MkII and Canon 200mm lens at f/2.8). The rings of colour around Sirius are an artifact of the sensor filter, I think!

Low in my northern winter sky is the brightest star in the sky of any season, Sirius. Just above and to the east of Sirius lies the Seagull Nebula (at top left), also called IC 2177, on the Canis Major-Monoceros border. Like many of these nebulas. the Seagull is too faint to easily see even with a telescope, but shows up well in photographs.


Lambda Orionis Nebula

Lambda Orionis Nebula with 200mm
With the Fornax Lightrack tracker and 200mm lens and filter-modified Canon 5D MkII. A stack of 10 x 3 minute exposures at ISO 800 with the filter-modified Canon 5D MkII and Canon 200mm lens at f/2.8.

This is the head of Orion, with the red supergiant star Betelgeuse at bottom left and the blue giant star Bellatrix right at bottom right. The brightest star at top is Meissa or Lambda Orionis, and is surrounded by a large and very faint area of hydrogen nebulosity. The open cluster around Meissa is catalogued as Collinder 69.

While the winter Milky Way might not look as bright and spectacular as the summer Milky Way of Sagittarius and Scorpius, it does contains a wealth of wonders that are treats for the eye and telescope … and for the camera.

PS.: The techniques for taking and processing images like these form the content of our new Deep Sky with Your DSLR video course now being promoted on KickStarter until the end of February, and available for purchase once it is published later this spring.

See my previous blog post for details.  Thanks and clear skies!

— Alan, February 17, 2019 / © 2019 Alan Dyer / AmazingSky.com 

 

The Amazing Sky of Carina and Centaurus


 

Carina-Centaurus Nebulas Mosaic - Version 1

Deep in the southern Milky Way lies one of the most spectacular regions of sky.

Located about as far south in the Milky Way as it gets you find this wonderful region in Carina and Centaurus.

The Carina Nebula (NGC 3372) at upper right is one of the finest nebulas in the sky for binoculars or any telescope.

At lower left is the Running Chicken Nebula (IC 2948) (aka the Lambda Centauri Nebula). By contrast, this nebula is mostly a photographic target, and is a challenge to see with a small telescope. But can you see the Chicken here?

Carina-Centaurus Nebulas Mosaic (with Labels)

The small red and magenta nebulas at centre are called NGC 3603 and NGC 3576.

The blue Southern Pleiades star cluster (IC 2602) is at bottom right.

The Pearl Cluster (NGC 3766) is above the Running Chicken at left. The cluster IC 2714 is to the right of the Chicken amid dark nebulas.

The Gem Cluster (NGC 3324) is above and right of the Carina Nebula but small and unresolved here.

The Football Cluster (NGC 3532) is top centre, though partly lost amid the rich starfield.

All told, this is one of the best areas in the sky for deep-sky wonders. But you must travel south to see it, to at least 20° North latitude.

This is a mosaic of three segments, taken with the camera in portrait orientation, stitched with Photoshop to make a square framing of the area. Each segment was a stack of 4 x 2-minute exposures at f/2.8 with the 200mm Canon L-series lens and filter-modified Canon 5D MkII at ISO 2500.

I shot this mosaic earlier in April from my observing site at Coonabarabran, Australia.

— Alan, May 4, 2017 / © 2017 Alan Dyer / amazingsky.com 

 

Toward the Centre of the Galaxy


Toward the Centre of the Galaxy

From southern latitudes the most amazing region of the sky shines overhead late on austral autumn nights. 

There is no more spectacular part of the Milky Way than the regions around its galactic centre. Or at least in the direction of the galaxy’s core.

We can’t see the actual centre of the Galaxy, at least not with the cameras and telescopes at the disposal of amateur photographers such as myself.

It takes large observatory telescopes equipped with infrared cameras to see the stars orbiting the actual centre of the Milky Way. Doing so over many years reveals stars whipping around an invisible object with an estimated 4 million solar masses packed into the volume no larger than the solar system. It’s a black hole.

By comparison, looking in that direction with our eyes and everyday cameras, we see a mass of stars in glowing clouds intersected by lanes of dark interstellar dust.

The top image shows a wide view of the Milky Way toward the galactic centre, taking in most of Sagittarius and Scorpius and their incredible array of nebulas, star clusters and rivers of dark dust, all located in the dense spiral arms between us and the galactic core.

Starclouds and Stardust – Mosaic of the Galactic Centre
This is a mosaic of 6 segments, each segment being a stack of 4 x 3-minute exposures at f/2.8 with the 135mm Canon L-Series

Zooming into that scene reveals a panoramic close-up of the Milky Way around the galactic centre, from the Eagle Nebula in Serpens, at left, to the Cat’s Paw Nebula in Scorpius, at right.

This is the richest hunting ground for stargazers looking for deep-sky wonders. It’s all here, with field after field of telescopic and binocular sights in an area of sky just a few binocular fields wide.

The actual galactic core area is just right of the centre of the frame, above the bright Sagittarius StarCloud.

Centre of the Galaxy Area
This is a stack of 5 x 5 minute exposures with the Borg 77mm f/4 astrograph and filter-modified Canon 5D MkII at ISO 1600, taken from Tibuc Cottage near Coonabarabran, NSW, Australia.

Zooming in again shows just that region of sky in an even closer view. The contrast between the bright star fields at left and the dark intervening dust at right is striking even in binoculars – perhaps especially in binoculars.

The visual impression is of looking into dark canyons of space plunging off bright plateaus of stars.

In fact, it is just the opposite. The dark areas are created by dust much closer to us, hiding more distant stars. It is where the stars are most abundant, in the dust-free starclouds, that we see farthest into the galaxy.

In the image above the galactic centre is at right, just above the small diffuse red nebula. In that direction, some 28,000 light years away, lurks the Milky Way’s monster black hole.

Milky Way Overhead Through Trees
This is a stack of 5 x 6-minute tracked exposures with the 15mm fish-eye lens at f/4 and Canon 5D MKII at ISO 1600. The trees appear to be swirling around the South Celestial Pole at lower right above the Cottage.

To conclude my tour of the galactic centre, I back out all the way to see the entire sky and the Milky Way stretching from horizon to horizon, with the galactic centre nearly overhead in this view from 3 a.m. earlier this week.

Only from a latitude of about 30° South can you get this impressive view, what I consider one of the top “bucket-list” sights the sky has to offer.

– Alan, April 17, 2016 / © 2016 Alan Dyer / www.amazingsky.com

 

The Wonder-Filled Winter Sky


Mosaic of the Wonder-filled Winter Milky Way

The sky of December contains an amazing array of bright stars and deep-sky delights.

At this time of year we peer out toward the edge of our Galaxy, in the direction opposite to what we see in July and August. Even though we are looking away from the centre of our Galaxy, the Milky Way at this time of year contains a stunning collection of sights – for the naked eye, binoculars or a telescope.

I can’t list them all here, but most are in the lead image above! The image is a mosaic of the northern winter Milky Way, including the brilliant stars and constellations in and around Orion the Hunter.

The Milky Way extends from Perseus in the north at top, to Canis Major in the south at bottom. Throughout the scene are dark lanes and dust clouds, such as the Taurus Dark Clouds at upper right.

The Milky Way is dotted with numerous red “hydrogen-alpha” regions of emission nebulosity, such as the bright Rosette Nebula at lower left and the California Nebula at upper right. The curving arc of Barnard’s Loop surrounds the east side of Orion. Orion is below centre, with Sirius, the night sky’s brightest star, at lower left.

The constellation of Taurus is at upper right and Gemini at upper left. Auriga is at top and Perseus at upper right.

There’s an unusually bright area in Taurus just right of centre in the mosaic which I thought might be an image processing artifact. No. It’s the Gegenschein – a glow of sunlight reflected off comet dust directly opposite the Sun.

Two highlights of this sky that are great regions for binoculars are the Hyades cluster in Taurus ….

The Hyades Cluster with Aldebaran
The Hyades open star cluster in Taurus with the bright star Aldebaran, not a part of the cluster iteslf. The smaller and more distant cluster NGC 1647 is at left. This is a telephoto lens image taking in a field similar to binoculars, and is a stack of 5 x 2.5-minute exposures with the 135mm lens at f/2 and Canon 5D MkII camera at ISO 800, plus two other exposures taken through the Kenko Softon filter to add the star glows. Taken from Quailway Cottage on Dec 7, 2015 using the iOptron Sky-Tracker.

…and the Belt and Sword of Orion.

The Hyades – the face of Taurus – is one of the nearest and therefore largest open star clusters.

Orion the Hunter, who battles Taurus in the sky, contains the famous Orion Nebula, here overexposed in order to bring out the much fainter nebulosity in the region.

The magenta and blue arcs in the image below are photographic targets, but the bright Orion Nebula in Orion’s Sword is easy in binoculars, shining below the trio of his Belt Stars.

Orion Belt and Sword Mosaic
A mosaic of the Sword and Belt region of Orion the Hunter, showing the diverse array of colourful nebulas in the area, including: curving Barnard’s Loop, the Horsehead Nebula below the left star of the Belt, Alnitak, and the Orion Nebula itself as the bright region in the Sword. Also in the field are numerous faint blue reflection nebulas. The reflection nebula M78 is at top embedded in a dark nebula, and the pinkish NGC 2024 or Flame Nebula is above Alnitak. The bright orange-red star at far right is W Orionis, a type M4 long-period variable star. This is a 4-panel mosaic with each panel made of 5 x 2.5-minute exposures with the 135mm Canon L-series telephoto wide open at f/2 and the filter-modified Canon 5D MkII at ISO 1250. The night was somewhat hazy which added natural glows on the stars. No filter was employed here. The camera was on the iOptron Sky-Tracker for tracking but no guiding. Shot from outside Quailway Cottage near Portal, Arizona, Dec 7, 2015. All stacking and stitching performed in Photoshop CC 2015. Stacking done with median combine stack mode to eliminate geosat trails through the fields.

For us in the northern hemisphere, Orion and company are winter sights. But for those down under, in the southern hemisphere, this is the summer sky. So pardon the northern chauvinism in the title!

Either way, on a dark, moonless night, get out and explore the sky around Orion.

TECHNICAL:

I shot the segments for the main mosaic at top on a very clear night on December 5, 2015 from the Quailway Cottage at Portal, Arizona. This is a mosaic of 8 segments, in two columns of 4 rows, with generous overlap. Each segment was made of 4 x 2.5-minute exposures stacked with mean combine stack mode to reduce noise, plus 2 x 2.5-minute exposures taken through the Kenko Softon filter layered in with Lighten belnd mode to add the star glows. Each segment was shot at f/2.8 with the original 35mm Canon L-series lens and the filter-modified (by Hutech) Canon 5D MkII at ISO 1600, riding on the iOptron Sky-Tracker. All stacking and stitching in Photoshop CC 2015. The soft diffusion filter helps bring out the star colors in this area of sky rich in brilliant giant stars.

— Alan, December 11, 2015 / © 2015 Alan Dyer / www.amazingsky.com

Shooting the Heart Nebula


Testing the Nikon D810a

Last night I shot into the autumn Milky Way at the Heart Nebula.

I’m currently just finishing off a month of testing the new Nikon D810a camera, a special high-end DSLR aimed specifically at astrophotographers.

I’ll post a more thorough set of test shots and comparisons in a future blog, but for now here are some shots from the last couple of nights.

Above is the setup I used to shoot the image below, shot in the act of taking the image below!

The Nikon is at the focus of my much-loved TMB 92mm refractor, riding on the Astro-Physics Mach One mount. The mount is being “auto-guided” by the wonderful “just-press-one-button” SG-4 auto-guider from Santa Barbara Instruments. The scope is working at a fast f/4.4 with the help of a field flattener/reducer from Borg/AstroHutech.

I shot a set of 15 five-minute exposures at ISO 1600 and stacked, aligned and averaged them (using mean stack mode) in Photoshop. I explain the process in my workshops, but there’s also a Ten Steps page at my website with my deep-sky workflow outlined.

IC 1805 Heart Nebula (92mm D810a)
The Heart Nebula, IC 1805, in Cassiopeia, with nebula NGC 896 at upper right and star cluster NGC 1027 at left of centre. This is a stack of 15 x 5-minute exposures with the Nikon D810a as part of testing, at ISO 1600, and with the TMB 92mm apo refractor at f/4.4 with the Borg 0.85x field flattener. Taken from home Nov 29, 2015.

The main advantage of Nikon’s special “a” version of the D810 is its extended red sensitivity for a capturing just such objects in the Milky Way, nebulas which shine primarily in the deep red “H-alpha” wavelength emitted by hydrogen.

It works very well! And the D810a’s 36 megapixels really do resolve better detail, something you appreciate in wide-angle shots like this one, below, of the autumn Milky Way.

It’s taken with the equally superb 14-24mm f/2.8 Nikkor zoom lens. Normally, you would never use a zoom lens for such a demanding subject as stars, but the 14-24mm is stunning, matching or beating the performance of many “prime” lenses.

The Autumn Milky Way (Perseus to Cygnus)
The Milky Way from Perseus, at left, to Cygnus, at right, with Cassiopeia (the “W”) and Cepheus at centre. Dotted along the Milky Way are various red H-alpha regions of glowing hydrogen. The Andromeda Galaxy, M31, is at botton. The Double Cluster star cluster is left of centre. Deneb is the bright star at far right, while Mirfak, the brightest star in Perseus, is at far left. The Funnel Nebula, aka LeGentil 3, is the darkest dark nebula left of Deneb. This is a stack of 4 x 1-minute exposures at f/2.8 with the Nikkor 14-24mm lens wide open, and at 24mm, and with the Nikon D810a red-sensitive DSLR, at ISO 1600. Shot from home, with the camera on the iOptron Sky-Tracker.

The D810a’s extended red end helps reveal the nebulas along the Milky Way. The Heart Nebula, captured in the close-up at top, is just left of centre here, left of the “W” forming Cassiopeia.

The Nikon D810a is a superb camera, with low noise, high-resolution, and features of value to astrophotographers. Kudos to Nikon for serving our market!

– Alan, November 30, 2015 / © 2015 Alan Dyer / www.amazingsky.com

 

Scenes at the Texas Star Party


The galactic centre region of the Milky Way in Sagittarius and Scorpius, over the upper field of the Texas Star Party, near Fort Davis, Texas, May 13, 2015. About 600 people gather here each spring for a star party under very dark skies near the MacDonald Observatory. Sagittarius is left of centre and Scorpius is right of centre with the planet Saturn the bright object at the top edge right of centre. The dark lanes of the Dark Horse and Pipe Nebula areas lead from the Milky Way to the stars of Scorpius, including Antares. The semi-circular Corona Australis is just clearing the hilltop at left of centre. This is a composite of 5 x 3 minute exposures with the camera tracking the sky for more detail in the Milky Way without trailing. Each tracked exposure was at ISO 1600. The ground comes from 3 x 1.5-minute exposures at ISO 3200 taken immediately after the tracked exposures but with the drive turned off on the tracker. All are with the 24mm lens at f/2.8 and filter-modified Canon 5D MkII camera. The ground and sky layers were stacked and layered in Photoshop. The tracker was the Sky-Watcher Star Adventurer. High haze added the natural glows around the stars — no filter was employed here.

The stars at night shine big and bright, deep in the heart of Texas.

Last week several hundred stargazers gathered under the dark skies of West Texas to revel in the wonders of the night sky. I was able to attend the annual Texas Star Party, a legendary event and a mecca for amateur astronomers held at the Prude Ranch near Fort Davis, Texas.

Some nights were plagued by clouds and thunderstorms. but here are some scenes from a clear night, with several hundred avid observers under the stars and Milky Way. Many stargazers used giant Dobsonian reflector telescopes to explore the faintest of deep-sky objects in and beyond the Milky Way.

A 360° panorama of the upper field of the Texas Star Party at the Prde Ranch near Fort Davis, TX, May 13, 2015, taken once the sky got astronomically dark. The panorama shows the field of telescopes and observers enjoying a night of deep-sky viewing and imaging. Venus is the bright object at right of centre and Jupiter is above it. The Zodiacal Light stretches up from the horizon and continues left across the sky in the Zodiacal Band to brighten in the east (left of centre) as the Gegeneschein. I shot this with a 14mm lens, oriented vertically, with each segment 60 seconds at f/2.8 and with the Canon 5D MkII at ISO 3200. The panorama is made of 8 segements at 45° spacings. The segments were stitched with PTGui software.
A 360° panorama of the upper field of the Texas Star Party at the Prde Ranch near Fort Davis, TX, May 13, 2015, taken once the sky got astronomically dark. The panorama shows the field of telescopes and observers enjoying a night of deep-sky viewing and imaging. Venus is the bright object at right of centre and Jupiter is above it. The Zodiacal Light stretches up from the horizon and continues left across the sky in the Zodiacal Band to brighten in the east (left of centre) as the Gegeneschein.
I shot this with a 14mm lens, oriented vertically, with each segment 60 seconds at f/2.8 and with the Canon 5D MkII at ISO 3200. The panorama is made of 8 segements at 45° spacings. The segments were stitched with PTGui software.

Observers at the Texas Star Party explore the wonders of the deep sky under the rising Milky Way, in May 2015. Sagittarius and Scorpius are in the background, with the centre of the Galaxy rising in the southeast. This is a single 30-second exposure at f/2 with the 24mm lens and Canon 5D MkII at ISO 4000.
Observers at the Texas Star Party explore the wonders of the deep sky under the rising Milky Way, in May 2015. Sagittarius and Scorpius are in the background, with the centre of the Galaxy rising in the southeast. This is a single 30-second exposure at f/2 with the 24mm lens and Canon 5D MkII at ISO 4000.

Expert deep-sky observers Larry Mitchell and Barbara Wilson gaze skyward with Larry’s giant 36-inch Dobsonian telescope at the Texas Star Party, May 2015. This is a single 60-second exposure with the 14mm lens at f/2.8 and Canon 5D MkII at ISO 3200.
Expert deep-sky observers Larry Mitchell and Barbara Wilson gaze skyward with Larry’s giant 36-inch Dobsonian telescope at the Texas Star Party, May 2015. This is a single 60-second exposure with the 14mm lens at f/2.8 and Canon 5D MkII at ISO 3200.

A deep-sky observer at the top of a tall ladder looking through a tall and large Dobsonian telescope, at the Texas Star Party, May 2015. Scorpius is rising in the background; Saturn is in the head of Scorpius as the bright star above centre. Anatares is just below Saturn. This is a single 30-second exposure at f/2.5 with the 24mm lens and Canon 5D MkII at ISO 6400.
A deep-sky observer at the top of a tall ladder looking through a tall and large Dobsonian telescope, at the Texas Star Party, May 2015. Scorpius is rising in the background; Saturn is in the head of Scorpius as the bright star above centre. Anatares is just below Saturn. This is a single 30-second exposure at f/2.5 with the 24mm lens and Canon 5D MkII at ISO 6400.

Circumpolar star trails over the upper field of the Texas Star Party, May 13, 2015. The star party attracts hundreds of avid stargazers to the Prude Ranch near Fort Davis, Texas each year to enjoy the dark skies. The three observing fields are filled with telescopes from the basic to sophisticated rigs for astrophotography. I aimed the camera to look north over the field to capture the stars circling around Polaris in circumpolar trails over about 1 hour. Some cloud and haze obscured parts of the sky. Lights from cities to the north add the sky glow at right. The streaks at top are from the stars of the Big Dipper. This is a stack of 55 exposures, each 1 minute long, at f/2.8 with the 14mm lens and Canon 5D MkII at ISO 3200. The foreground comes from a single image in the series, masked and layered in Photoshop. The images were stacked using the Long Trails tapering effect with the Advanced Stacker Actions from Star Circle Academy.
Circumpolar star trails over the upper field of the Texas Star Party, May 13, 2015. I aimed the camera to look north over the field to capture the stars circling around Polaris in circumpolar trails over about 1 hour. Some cloud and haze obscured parts of the sky. Lights from cities to the north add the sky glow at right. The streaks at top are from the stars of the Big Dipper.
This is a stack of 55 exposures, each 1 minute long, at f/2.8 with the 14mm lens and Canon 5D MkII at ISO 3200. The foreground comes from a single image in the series, masked and layered in Photoshop. The images were stacked using the Long Trails tapering effect with the Advanced Stacker Actions from Star Circle Academy.

I extend my thanks to the organizers for the great event, and for the opportunity to speak to the group as one of the featured evening speakers. It was great fun!

– Alan, May 17, 2015 / © 2015 Alan Dyer / www.amazingsky.com

Nova Star in Sagittarius


Nova Star in Sagittarius

It’s a nova needle in a Milky Way haystack – an exploding star appears in Sagittarius. 

On March 15 a very observant amateur astronomer in Australia spotted a star in Sagittarius that wasn’t there the night before. It was a nova, Latin for “new.”

But this was not a new star forming, but an old star in the process of dying.

This star is likely an ancient white dwarf drawing material off a close companion. When the in-falling material builds up on the surface of the white dwarf it ignites in a nuclear explosion, causing the star to brighten, in this case by hundreds of times.

At its peak last week, Nova Sagittarii was just bright enough to see naked eye. It is now below 5th magnitude and barely naked eye. In my long exposure photo it appears lost amid the blaze of stars in the Sagittarius Milky Way.

Still, this was the brightest nova visible from the northern hemisphere in many years. Indeed, we haven’t had a really bright naked-eye nova since the 1970s.

Considering all those stars, you’d think some would blow up for us to enjoy!

– Alan, March 26, 2015 / © 2015 Alan Dyer / www.amazingsky.com

Lovejoy Passes the Pleiades


Comet Lovejoy and the Pleiades (Jan 18, 2015)

Tonight Comet Lovejoy paired with the Pleiades star cluster.

Sunday, January 18 was the night to catch the ever-photogenic Comet Lovejoy at its best and closest to the Seven Sisters, the Pleiades. Its long blue ion tail stretched back past the Pleiades.

I thought the tail would be passing right over the star cluster, but not so. At least not when I was shooting it at about 7:30 pm MST.

Still, the combination made a fine pairing of cosmic blue objects for the camera. The top image is with a 135mm telephoto.

Comet Lovejoy in the Winter Sky (Jan 18, 2015)

This wide-angle image, with a 24mm lens, takes in many of the northern winter constellations, from Orion at bottom, to Auriga at top, with Taurus in the middle. Notice the dark tendrils of the Taurus Dark Clouds.

At right, beside the Pleiades, is the green and blue comet, with its tail reaching back past the Pleiades.

I shot both images from the dark skies of City of Rocks State Park, New Mexico, which has proven to be one of the finest places on the planet for watching Lovejoy!

– Alan, January 18, 2015 / © 2015 Alan Dyer / www.amazingsky.com 

Free Sky Calendar for a Starry New Year


Sky Calendar Front Page

As a special New Year’s gift I have prepared a free Calendar of celestial events for 2015.

I have lots of photos and I maintain a personal calendar to remind me of the year’s astronomical events. So why not combine them into a pictorial sky calendar anyone can use!

So I’ve prepared a free 2015 Sky Calendar as a PDF you can download.

To get it, please visit my website page at http://www.amazingsky.com/about-alan.html and scroll to the bottom of the page for a link. It’s a 5 meg download.

The sky events listed are for North America. While most will be visible around the world the timing may be off for other locations. Many thanks for visiting and following my blog this past year. I wish everyone a happy and celestial 2015.

– Alan, December 29, 2014 / © 2014 Alan Dyer / www.amazingsky.com 

Comet and Cluster


Comet Lovejoy (C/2014 Q2) on Dec 27, 2014

Comet Lovejoy passes near the globular cluster M79 in this image from Saturday, December 27. 

Here is the comet that is making the news, as it comes into view in northern skies, now sporting a decent tail of gas streaming away from its cyan-coloured head.

Comet Lovejoy (C/2014 Q2) is proving to be a fine photogenic comet and an easy target for binoculars. Visually it still looks like a large fuzzy star, though I could spy a sign of a faint tail on Saturday night, at least through binoculars.

This weekend it passed the small, faint globular cluster Messier 79, seen here at upper right. It was very close to M79 Sunday night, but alas, clouds blew in, obscuring the view from here in New Mexico.

The Moon is now in the sky with the comet, leaving no dark sky time to see the comet after moonset. That will be the case for another two weeks or so. But by mid January the Moon will be gone and the comet will be much higher in the sky, moving up through Taurus.

From a dark site, it may be easily visible to the naked eye at that time, a surprising bonus for the winter, as this comet was never expected to get this bright.

Thank you, Terry Lovejoy, for finding your comets in Australia and sending them our way!

– Alan, December 28 / © 2014 Alan Dyer / www.amazingsky.com 

A Cosmic Christmas Wreath


IC 1396 & Garnet Star in Cepheus

A cosmic Christmas wreath glows in the sky, adorned by a celestial garnet.

This nebula, known as IC 1396, shines in the constellation of Cepheus the king, now high overhead on early winter evenings in the northern hemisphere. It’s a bubble of gas blown by new stars amid the interstellar wreath.

At top, shining like a Christmas light on the wreath, is an orange star. This is Mu Cephei, also known as the Garnet Star. It’s a red supergiant, roughly 1,500 times bigger than our Sun. If it replaced our Sun at the centre of our solar system it would engulf all the planets out to and including Jupiter.

Be happy Mu sits 1,000 light years away!

Happy holidays! And happy solstice. Winter arrives in the northern hemisphere at 6:03 p.m. EST on Sunday, December 21. That’s the shortest day and longest night of the year, for all those north of the equator.

– Alan, December 20, 2014 / © 2014 Alan Dyer

Supernova Remnant & Star Cluster


Supernova Remnant & Star Cluster in Gemini

A bubble of glowing gas blows away from an ancient dying star, next to a cluster of new stars in Gemini.

This image, from a week ago, captures contrasting stages in the life of a star.

At left is a crescent-shaped bubble of gas called IC 443, or the Jellyfish Nebula, billowing away from the site of an ancient supernova explosion, when a giant star ended its life in a blast thousands of years ago. Estimates put its age as between 3,000 and 30,000 years.

At upper right is the bright open star cluster, Messier 35, a gathering of hundreds of comparatively new stars at the beginning of their lives. M35 lies 2,800 light years away, close enough that its stars are nicely resolved in my photo and in any small telescope. M35 is one of the showpieces of the winter northern sky.

Just below M35 you can see a fuzzy glow. It’s another star cluster, NGC 2158. However, its great distance of 11,000 light years makes it appear as a small, partially-resolved glow, a nice contrast in clusters near and far.

IC 443 Supernova Remnant in Gemini

This image focuses on IC 443, sitting between the stars Eta (right) and Mu Geminorum. The field is filled with other faint nebulosity, all part of the cycle of star birth and death.

– Alan, December 7, 2014 / © 2014 Alan Dyer

The Seven Sisters in a Silver Braid


M45 Pleiades Star Cluster, the Seven Sisters“Many a night I saw the Pleiads, rising thro’ the mellow shade,

Glitter like a swarm of fireflies tangled in a silver braid.”

– Alfred, Lord Tennyson

These are the famous Seven Sisters, the Pleiades, caught two nights ago in New Mexico skies. This bright star cluster stands out easily to the unaided eye in the winter sky, shining in the shoulder of Taurus.

What the eye does not see is the “silver braid” – the dim dust that surrounds the Pleiades. The stars light the dust, causing it to shine blue near the stars. Farther out, the dust is much dimmer and glows with pale tints of cyan and red.

The dust clouds were once thought to be what was leftover from the formation of the stars, now estimated to have occurred about 100 million years ago. However, current theory suggests that the natal dust of the Pleiads would have long since dispersed.

Instead, the silvery braids of dust that surround the Seven Sisters are just nearby dust clouds in Taurus that the stars are passing through, and illuminating with their hot blue light.

The Pleiades, as familiar as they are – they have been mentioned in ancient texts and myths dating back thousand of years – remain a source of scientific controversy. Astronomers argue over their distance, with different methods providing different results. But the best recent measurement puts them 440 light years away.

Technical notes: This is a stack of 10 x 12 minute exposures at ISO 400 with the Canon 5D MkII camera and 92mm TMB refractor at f/4.4. I shot the images November 16 from near Silver City, New Mexico.

– Alan, November 18, 2014 / © 2014 Alan Dyer

 

Both the Heart and Soul of Cassiopeia


Heart & Soul Nebulas (IC 1805 and IC 1848) in Cassiopeia

Here are both the heart and the soul of Cassiopeia the Queen.

Two days ago I posted an image of the Soul Nebula. Now, here is the matching Heart Nebula, in a mosaic of the glorious region of the Milky Way called the Heart and Soul Nebulas located in the constellation of Cassiopeia.

They are otherwise respectively called IC 1805 and IC 1848. Amid the swirls of nebulosity are numerous clusters of stars, such as NGC 1027 just above centre. The separate patch of nebulosity at upper right is NGC 896.

I shot the frames for this 3-segment mosaic over two nights, with one segment taken from the frames that made up the previous post. Plus I shot two others to span the region of the Milky Way that is about seven degrees long, a binocular field.

Each of the 3 segments is a stack of 12 frames, with each frame a 6-minute exposure. I used the filter-modified Canon 5D MkII and shot through the TMB 92mm apo refractor at f/4.4. All processing was in Photoshop, including the mosaic assembly.

In all, it’s the best image I’ve taken of this much-shot area of the sky. It really brings out the diversity in star colours, and sky colours, from the dusty orange-brown region at left, to the inky dark dustless region at far right.

– Alan, November 18 2014 / © 2014 Alan Dyer

 

The Soul of Cassiopeia


IC 1848, the Soul Nebula, in Cassiopeia

The Soul Nebula glows from within the constellation of Cassiopeia the Queen.

I shot this image last night, capturing an object prosaically known as IC 1848, but more popularly called the Soul Nebula.

It is often depicted framed with a companion nebula just “off camera” here to the right, called the Heart Nebula. Thus they are the Heart and Soul. Both shine on the eastern side of Cassiopeia the Queen.

Here I’m framing just the Soul, taking in some of the faint nebulosity to the left of the main nebula, including a tiny object called IC 289, a star-like planetary nebula at upper left.

I like this image for its variety of subtle colours, not only the reds and magentas in the bright nebula, but also in the dark sky around it from dim dust adding faint yellows, browns and even a touch of green.

The Soul Nebula lies 6,500 light years away in the Perseus Arm, the next spiral arm out from ours in the Milky Way. On northern autumn nights this region of the sky and Milky Way lies high overhead.

For the technically minded:

The image is a stack of 20 six-minute exposures, taken with a filter-modified Canon 5D Mark II at ISO 800. I was shooting through one of my favourite telescopes for deep-sky photography, the TMB (Thomas M. Back-designed) 92mm apo refractor, working at a fast f/4.4 using a Borg 0.85x field flattener and focal reducer.

I used one of Noel Carboni’s “Astronomy Tools” Photoshop actions to add the “diffraction spikes” on the stars. They are artificial (refractors don’t produce spikes on stars) but they add a photogenic touch to a rich starfield.

I shot this from the backyard of my New Mexico winter home.

– Alan, November 16, 2014 / © 2014 Alan Dyer

Truly Interstellar


M26 Open Cluster and NGC 6712 Globular Cluster

We gaze into the interstellar depths of the Milky Way through uncountable stars.

In this telescopic scene we look toward the Scutum Starcloud, and next spiral arm in from ours as we gaze toward the core of the Galaxy.

The field is packed with stars, seemingly crowded together in interstellar space. In fact, light years of empty space separate the stars, even in crowded regions of the Milky Way like this.

Two dense clusters of stars stand out like islands in the sea of stars. At lower right is Messier 26, an open cluster made of a few dozen stars. Our young Sun probably belonged to a similar family of stars billions of years ago. M26 lies 5,200 light years away.

At upper left is a condensed spot of light, made of hundreds of thousands of density packed stars in the globular cluster known only as NGC 6712. Though much larger and denser than M26, NGC 6712 appears as a tiny spot because of its remoteness – 23,000 light years away, a good part of the distance toward the centre of the Galaxy.

Look carefully (and it may not be visible on screen) and you might see a small green smudge to the left of NGC 6712. That’s a “planetary nebula” called IC 1295. It’s the blown off atmosphere of an aging Sun-like star. It’s what our Sun will become billions of years from now.

At top is a vivid orange-red star, S Scuti, a giant pulsating star nearing the end of its life.

A truly interstellar scene.

– Alan, November 9, 2014 / © 2014 Alan Dyer

 

 

Mars and M22


Mars and M22 Cluster

Mars shines near the globular star cluster Messier 22 in Sagittarius.

This week Mars has been passing near one of the brightest globular star clusters, M22. I caught the pair tonight, November 8, as they sank into the southwestern sky.

The two form a contrasting pair, with red Mars now 260 million kilometres away, far enough that its light takes 13 minutes to reach Earth. However, blue M22 lies so far away, toward the galactic core, that its light take 10,000 years to reach Earth.

Mars appeared closer to M22 earlier this week but tonight was the first night with a narrow window of dark sky between twilight and moonrise, allowing me to shoot the pair.

I shot the image through a telescope with a short focal length of 400mm, taking in a field of about 5 by 3 degrees, the field of high-power binoculars. The image is a stack of eight 2-minute exposures at f/4.5 with the TMB 92mm refractor and Canon 6D at ISO 800.

– Alan, November 8, 2014 / © 2014 Alan Dyer

The Head of the Celestial Scorpion


 

Scorpius Head & Antares (135mm 5DII) v2The head of Scorpius is laced with colourful nebulas, both bright and dark. 

This is an image from two nights ago, from the dark skies of southeast Arizona. It takes in the head of Scorpius, from yellow Antares at lower left as the heart of the Scorpion, to the blue stars at right that mark his head.

The remarkable feature of this region of sky is its colour. No where else in the sky do we see (or I should say, does the camera see) such a spectrum of colourful nebulas. Dark brown lanes run down from the constellation Ophiuchus at left. They meet up with a yellow patch of nebulosity caused by dust reflecting the yellow-orange light of the giant star Antares.

Hot blue stars light up other dusty patches, while the magenta nebulas are created by gas emitting light, not just reflecting light from nearby stars.

A close-up of the region, shot in Australia last month, appears in my blog post from April 17, Stars Scenes in Scorpius. The image above, shot with a 135mm telephoto lens, takes in an area of sky that typical binoculars would frame.

But the eye sees only a hint of the detail, and none of the colour, hidden in the heart of Scorpius.

– Alan, May 6, 2014 / © 2014 Alan Dyer

 

Nebulas, Clusters and Starfields, Oh My!


Centre of the Galaxy Mosaic

There’s no more spectacular region of the sky than the Milky Way toward the centre of the Galaxy.

What a perfect night it was last night. After moonset between 2 and 3:30 a.m. I shot a series of images around the centre of the Galaxy area and stitched them into a big mosaic of the Milky Way.

The scene takes in the Milky Way from the Eagle and Swan nebulas at top left, down to the Messier 6 and 7 open clusters in Scorpius at bottom. Standing out is the large pink Lagoon Nebula left of centre and the huge region of dark dusty nebulosity popularly called the Dark Horse at right of centre. It’s made of smaller dark nebulas such as the Pipe Nebula and tiny Snake Nebula.

At upper left is the bright Small Sagittarius Starcloud, aka Messier 24, flanked by the open clusters M23 and M25. There are a dozen or more Messier objects in this region of sky.

The actual centre of the Milky Way is obscured by dark dust but lies in the direction just below the centre of the frame, amid one of the bright star clouds that mark this amazing region of sky.

I shot the images for this mosaic from a site near Portal, Arizona, using a 135mm telephoto lens and filter-modified Canon 5D Mark II riding on an iOptron SkyTracker to follow the stars. The mosaic is made of 6 panels, each a stack of five 3-minute exposures. They were all stacked and stitched in Photoshop CC. The full version is 8000 by 9000 pixels and is packed with detail.

I think the result is one of the best astrophotos I’ve taken! It sure helps to have Arizona skies!

– Alan, May 5, 2014 / © 2014 Alan Dyer

 

 

Splendid Southern Star Clusters


NGC 2477 and NGC 2451 in Puppis (77mm 5DII)

The southern Milky Way is populated by the sky’s best clusters of stars.

Here are three of the southern sky’s best star clusters, in portraits I took earlier this month from Australia.

At top, my main image takes in a great contrasting pair of star clusters. Both lie in the constellation of Puppis, once part of the ship Argo Navis.

At left is the stunningly rich NGC 2477, so packed with stars it almost ranks as a globular cluster, not one of the sparser open clusters. At least that’s the impression it gives in the eyepiece. But instead of containing hundreds of thousands of stars, as do globulars, NGC 2477 “only” has 300 stellar members. They are just very tightly packed in one of the richest open star clusters in the sky. If it had been farther north NGC 2477 would certainly rate as one of the top 100 sky sights, and carry some memorable name after a fanciful resemblance to who knows what! Instead, it carries but a catalog number.

Next to it, at right, is NGC 2451, more typical of open clusters. It has a central bright star, this one naked eye, surrounded by 40 or so lesser stars of contrasting colour and brightness. The two clusters make a great side-by-side comparison in any low-power telescope.

NGC 6067 in Norma Star Cloud (77mm 5DII)

Much farther along the southern Milky Way is this rich open cluster (above), NGC 6067, in Norma, itself embedded in one of the richest star clouds of the southern Milky Way, the Norma Star Cloud. Here you are gazing for 6800 light years toward the cluster which shines suspended against the background of the even more distant inner arms of our spiral galaxy.

So NGC 6067 looks a little like an island of blue stars amid the dust-reddened background of more distant stars in the Milky Way — an island in a sea of stars.

– Alan, April 29, 2014 / © 2014 Alan Dyer

 

 

The Night Sky’s Two Brightest Stars


Sirius, Canopus & Gum Nebula (35mm 5DII)

The two brightest stars in the night sky shine in the southern sky.

Here are Sirius (at right) and Canopus (at bottom left), the brightest and second brightest stars in the night sky, together near the southern Milky Way.

My image also captures the huge loops of the Gum Nebula, thought to be the remains of a supernova that blew up a million years ago. It’s utterly invisible to the naked eye, but Sirius and Canopus stand out as brilliant stars even from light polluted sites.

Sirius can be seen from northern latitudes but Canopus is below the horizon for any location north of 37° North or so. I shot this image from Australia where these stars pass overhead.

Sirius is a hot blue-white star 8.6 light years away. Canopus appears slightly dimmer but only because it lies much farther away, at some 310 light years. In reality it is a supergiant yellow-white star that shines with a luminosity 15,000 times that of our Sun.

Canopus to Carina with LMC (35mm 5DII)

This image takes in Canopus at bottom right, next to the Large Magellanic Cloud, and with the southern Milky Way sweeping across the top, with the Carina Nebula and its attendant star clusters at top left and parts of the Gum Nebula at right.

Here are a few cocktail party facts about Canopus:

• In 480,000 years its motion around the Galaxy will bring Canopus close enough to Earth that it will become the brightest star in our night sky, outranking Sirius.

• The origin of its name is a mystery. One idea is that the star is named for the pilot of the ship that took Menelaus to Troy on the quest to re-capture Helen.

• Canopus, the star, was used in ancient times as a key navigation star for those sailing to southern seas, as it would have risen above the southern horizon from latitudes below 35° North back around 2000 BCE.

• Today, Canopus is charted as the brightest star in the constellation of Carina the Keel, part of the ancient constellation of Argo Navis, named for the ship sailed by Jason and the Argonauts.

— Alan, April 27, 2014 / © 2014 Alan Dyer

 

Stellar Graveyard in Vela


Vela Supernova Remnant (77mm 5DII)

This is what’s left of a star that exploded in ancient times.

This is the Vela Supernova Remnant, an object in the southern sky in the constellation of Vela the Sail. The wispy tendrils of magenta and cyan are all that’s left of the outer layers of giant star that exploded about 12,000 years ago.

Cluttering the field at left are amorphous patches of star-forming nebulosity that are part of the much larger Gum Nebula complex.

The supernova was only about 800 light years away so it would have been a brilliant sight in the sky to neolithic observers, far outshining any other stars. But no record exists of anyone seeing it.

The star didn’t destroy itself completely – its core collapsed to form a pulsar, an ultra-dense ball of neutrons, in this case spinning about 11 times a second. The pulsar is in this field but it’s much too faint to show up in visible light.

I shot this earlier this month from Australia where Vela sails directly overhead. The field is about 6° by 4°, the amount of sky framed by high power binoculars. The brighter parts of the Vela Remnant can be picked out in large amateur telescopes – I’ve seen bits of it in my 10-inch telescope – but this is certainly a challenging object to see, even with aided eyes.

— Alan, April 23, 2014 / © 2014 Alan Dyer

 

 

Star Scenes in Scorpius


Scorpius Overhead (50mm 5DII)

Scorpius, one of the most photogenic of constellations, contains a wealth of amazing sky sights.

My trip to the land down under is coming to an end but I’m still working through the dozens of deep-sky images I was able to take under the southern stars. The wide-field scene above takes in all of Scorpius, shot with the constellation sitting directly overhead in the pre-dawn hours of an austral autumn. You can trace the scorpion’s winding shape down from his head and claws at top, to his curving stinger tail at bottom.

M6 and M7 Star Clusters in Scorpius (77mm 5DII)

Off the stinger of the scorpion shine two naked-eye star clusters, Messier 6 and 7 (the close-up photo above). M6 is the Butterfly Cluster, seen here sitting in a dark region of the Milky Way at upper right. Its companion, M7, a.k.a. Ptolemy’s Cluster at left of the frame, is lost amid the bright star fields  that mark the direction of the galactic core.

NGC 6334 Cat's Paw Nebula (77mm 5DII)

In the curving tail of the scorpion lie two patches of nebulosity. At upper left is NGC 6357, but the triple-lobed NGC 6334 at bottom right is also known as the Cat’s Paw Nebula.

False Comet NGC 6231 Area (77mm 5DII)

Further up the tail of the scorpion sits this fabulous region of space that is a stunning sight in binoculars. NGC 6231 is the blue star cluster at bottom, which garnered the name The False Comet Cluster back in early 1986 when many people mistook its fuzzy naked eye glow for Comet Halley then passing through the area. The camera reveals the region filled with glowing hydrogen gas.

Antares & Rho Ophiuchi Area (77mm 5DII)

But the standout region of Scorpius lies at its heart. Here, the yellow-orange star Antares lights up a dusty nebula surrounding it, reflecting its yellow glow. At top, another dusty nebula surrounds the star Rho Ophiuchi, reflecting its blue light. Glowing hydrogen gas adds its characteristic magenta tints. This is one of the most colourful regions of the Milky Way.

I shot these images with 50mm normal and 300mm telephoto lenses two weeks ago during the OzSky Star Safari near Coonabarabran, NSW, Australia. For all I used a filter-modified (by Hutech) Canon 5D Mark II camera.

— Alan, April 17, 2014 / © 2014 Alan Dyer

 

The Milky Way of the Deep South


Vela to Centaurus with Crux & Carina (35mm 5DII)

The Milky Way of the southern hemisphere contains some astonishing deep-sky sights.

The lead image above shows the section of the Milky Way that extends farthest south, and so is visible only from tropical latitudes in the north and, of course, from the southern hemisphere. I shot these images this past week in Australia.

The wide-angle image above takes in the southern Milky Way from Vela, at right, to Centaurus, at left. In the middle is the Southern Cross (left of centre), the Carina Nebula complex and surrounding clusters, and the False Cross at right of frame. The close-ups below zoom into selected regions of this area of the Milky Way. All are spectacular sights in binoculars or any telescope.

Coal Sack and Jewel Box (77mm 5DII) #2

This image frames the left side of Crux, the Southern Cross. The bright stars are Becrux (top) and Acrux (bottom). Just below Becrux is the compact and brilliant Jewel Box cluster, aka NGC 4755. Below it are the dark clouds of the Coal Sack, which in photos breaks up into discrete segments and patches.

 

Pearl Cluster and Lambda Centauri Nebula (77mm 5DII)

This region is a favourite of mine for images and for visual scanning in any telescope. The large nebula is the Lambda Centauri complex, also labelled the Running Chicken Nebula. Can you see its outline? Above it is the beautiful Pearl Cluster, aka NGC 3766.

 

Carina Nebula and Clusters (77mm 5DII)

This is the standout object in the deep south – the Carina Nebula complex. I’ve shot this many times before but this is my best take on it. At upper left is the Football Cluster, NGC 3532, while at upper right is the Gem Cluster, NGC 3293.

Seeing this area in person is worth the trip to the southern hemisphere. There are now many photographers up north who have shot marvellous images of Carina but using robotic telescopes. They have never actually seen the object for themselves. They print the images upside down or sideways, a sign of their detachment from the real sky.

You have to stand under the southern stars to really appreciate the magnificence of the Milky Way. All else is just data taking.

– Alan, April 5, 2014 / © Alan Dyer

 

Zooming into the Centre of the Galaxy


Sagittarius and Scorpius Milky Way (35mm 5DII)

A series of closer images zooms us into the Milky Way looking toward the centre of our Galaxy

Here are some images I took this past week at the OzSky Star Safari near Coonabarabran, Australia. The lead image above is a wide-angle lens image of all of Scorpius (above and to the right) and Sagittarius (below and to the left) straddling the Milky Way and its bright glowing core. The direction of the galactic centre is just left of centre of the image. We can’t see the actual centre of the Milky Way with our eyes and normal cameras because there are just too many stars and obscuring dust lanes in between us and the core.

The dust forms marvellous patterns across the glowing Milky Way — see the Dark Horse prancing at left? Long tendrils of dust reach from the feet of the Horse to the bright yellow star at top, Antares, the heart of Scorpius.

The Centre of the Milky Way (50mm 60Da)

This image with a longer lens zooms in closer to the bright Sagittarius Starcloud around the heart of the Galaxy. All along it you can see red and pink nebulas, from the Cat’s Paw at upper right to the Eagle Nebula at lower left. The larger pink object at centre is the Lagoon Nebula.

The next image zooms into the area at the centre of the above shot, just right of the Lagoon.

Sagittarius Starcloud (77mm 5DII)

This is the star-packed Sagittarius Starcloud. Everything you see is stars. Millions of stars.

I took this shot with a 300mm telephoto — a small telescope actually, the gear shown below. It’s what I was using most of this past week to shoot the Australian southern sky.

Borg 77mm Astrograph in Australia

This is some of my Oz gear, the equipment (except for the camera and autoguider on top) that stays in Australia for use every year or two. The mount is an Astro-Physics 400 and the scope is the Borg 77mm f/4 astrograph. I used it for the close-up photo.

The gear all worked great this time. I’ll have more photos to post shortly as my connection allows. Tonight, I am at the Parkes Radio Observatory where the internet connection is as good as it gets!

— Alan, April 4, 2014 / © 2014 Alan Dyer

 

 

 

Centre of the Galaxy Rising


Galactic Centre Rising from Australia #2 (15mm 60Da)

The centre of our Galaxy rises above the gum trees of Australia.

This was the scene at 3 a.m. this week at our OzSky star party, as the stars of Scorpius and Sagittarius rise into the eastern sky, a magnificent view of the bright core of the Milky Way rising into view.

The image shows the intricate lacework of dark dust that lines the Milky Way – the stardust of which we are made. The bright star at upper left is Antares, the heart of the Scorpion.

This is one of the views you travel to the southern hemisphere to see. It is an unforgettable sight, one of the best the sky has to offer.

– Alan, April 2, 2014 / © 2014 Alan Dyer

 

Our Neighbour Galaxy, the Large Magellanic Cloud


Large Magellanic Cloud (77mm Borg & 5DII)

One of our nearest galactic neighbours contains an astonishing collection of nebulas and star clusters.

This is the money shot — top of my list for targets on this trip to Australia. This is the Large Magellanic Cloud, a satellite galaxy of our Milky Way. At “just” 160,000 light years away, the LMC is in our galactic backyard. Being so close, even the small 77mm telescope I used to take this image resolves numerous nebulas, star clusters, and a mass of individual stars. The image actually looks “noisy” from being filled with so many stars.

I’ve oriented and framed the Cloud to take in most of its main structure and objects. One can spend many nights just visually exploring all that the LMC contains. It alone is worth the trip to the southern hemisphere.

At left is the massive Tarantula Nebula, a.k.a. NGC 2070. At upper right is the LMC’s second best nebula, the often overlooked NGC 1763, also known as the LMC Lagoon. In between are many other magenta and cyan tinted nebulas.

I’ve shot this object several times but this is my best shot so far I think, and my first with this optical system in several years.

I used a Borg 77mm aperture “astrograph,” a little refractor telescope optimized for imaging. It is essentially a 330mm f/4 telephoto lens, but one that is tack sharp across the entire field, far outperforming any camera telephoto lens.

This shot is a stack of six 10-minute exposures at ISO 800 with the filter-modified Canon 5D MkII camera. The autoguider worked perfectly. And yet, I shot this in clear breaks between bands of clouds moving though last night. The night was humid but when the sky was clear it was very clear.

Next target when skies permit: the Vela Supernova Remnant.

– Alan, March 25, 2014 / © 2014 Alan Dyer

 

A Dreamy Carina Nebula


Carina Nebula in Haze (77mm 5DII)

The Carina Nebula glows among the colourful southern stars.

I’ve shot this field many times over the years in visits to the southern hemisphere but never with a result quite like this. Last night the sky was hazy with high cloud but I shot anyway. The result is a “dreamy” rendition of the Carina Nebula and its surrounding clusters of stars. At upper left is the Football Cluster, NGC 3532, while at upper right is the Gem Cluster, NGC 3293.

As with my previous post, the haze brings out the star colours, filling the field with pastel shades. It is one of the finest fields in the sky, worth the trip down under.

Alas, skies have clouded up tonight with only a few bright stars and Mars shining through. And the forecast is for rain for the next few days. So I may get lots of writing done at my Aussie retreat.

As a technical note: I shot this with the little 77mm Borg Astrograph, essentially a 300mm f/4 telephoto lens that is tack sharp across a full frame camera, like the Canon 5D MkII I used here. It was riding on my Astro-Physics 400 mount and guided flawlessly with the Santa Barbara SG4 auto-guider. The image is a stack of four 8-minute exposures. All the gear, much of it stored here in Australia between my visits, is working perfectly.

– Alan, March 23, 2014 / © 2014 Alan Dyer

 

The Pleiades – The Stellar Seven Sisters


M45, the Pleiades Cluster (92mm 5DII)

The stars of the Pleiades sit amid a dusty sky in Taurus.

These are the famous Seven Sisters of Greek legend, known as the Pleiades. They are the daughters of Atlas and Pleione, who are also represented by stars in the cluster. Many cultures around the world tell stories about these stars, but in Greek tradition their appearance signalled the summer sailing season in the Mediterranean. The Pleiades first appear at sunset in the eastern evening sky in autumn and put in their last appearance in the western sky in spring.

One story has it they were placed in the sky to recognize their devotion to their father Atlas and his unending labour in holding up the heavens. They are the half-sisters of the Hyades, another nearby cluster of stars in Taurus. Other stories describe the Pleiades as the Seven Doves that carried ambrosia to the infant Zeus.

A seldom-used name now for this cluster is the Atlantides, from the plural form of Atlas, their father. Thus, these sisters gave their name to the Atlantic Ocean, a vast and uncharted sea until the 16th century. The term “atlas,” first used by Mercator for a book of maps, comes not from the Pleiades’ father but from a real-life king in Morocco who supposedly made one of the first celestial globes.

I shot this portrait of the Sisters a few nights ago, stacking a set of five 15-minute exposures with the TMB 92mm refractor and Canon 5D MkII at ISO 800. I processed the image to bring out the faint clouds of dust that pervade the area.

The Pleiades are passing through dust clouds in Taurus and lighting them up. The stars are embedded in dust, lit blue by the light of the hot stars. But even farther out you can see wisps of dust faintly illuminated by the light of the Pleiades.

The stars are thought to be about 100 million years old, quite young as stars go. They formed together in a massive nebula that has long since dissipated, and will travel together for another few hundred million years until the sister stars go their own way around the Galaxy. The stellar family that gave rise to so many legends around the world will be scattered to the stars.

– Alan, October 12, 2013 / © 2013 Alan Dyer

A Star-Filled Scene in Cassiopeia


M52 & NGC 7635 Bubble Nebula (92mm 5DII)

A star cluster and nebulas highlight a glorious starfield in Cassiopeia.

I shot this three nights ago on a very clear autumn evening. The telescope field takes in the star cluster Messier 52 at upper left, a cluster of 200 stars about 5000 light years away. It is one of the best objects of its class for viewing in small telescopes. Charles Messier found it in 1774 as part of his quest to catalog objects that might be mistaken for comets.

The brightest area of nebulosity below M52 is the Bubble Nebula, aka NGC 7635, found in 1787 by William Herschel. It’s an area of star formation marked by a central bubble of gas (just visible on the scale of my photo) being blown by the winds from a hot central star. The Bubble can be seen in amateur telescopes but is a tough target to spot.

Above the Bubble is a small bright nebula, NGC 7538.

Below the Bubble lies a larger claw-like nebula known only as Sharpless 2-157, an object that shows up only in photos.

In all, it’s a complex and beautiful field, set in the constellation of Cassiopeia the Queen.

A footnote for the technically minded: This is a stack of 5 x 15 minute exposures with a filter-modified Canon 5D MkII at ISO 800 shooting through a TMB 92mm apo refractor at f/4.8, mounted on an Astro-Physics Mach 1 mount guided by a Santa Barbara SG-4 autoguider.

– Alan, October 11, 2013 / © 2013 Alan Dyer

 

The Veil Nebula in Cygnus


NGC 6960 & 6992-5 Veil Nebula (92mm 5DII)

This is what’s left of a star that exploded thousands of years ago.

I shoot this object every year or two, so this is my 2013 take on the Veil Nebula. For last year’s see Star Death Site, a post from September 2012.

The Veil Nebula is a supernova remnant. The lacework arcs are what’s left of a massive star that blew itself to bits in historic times. This object, one of the showpieces of the summer sky for telescope users, is now high overhead at nightfall, off the east wing of Cygnus the swan.

I shot this a couple of nights ago using a 92mm-aperture refractor that provides a wide field of view to easily frame the 3-degree-wide extent of the nebula. The image is a stack of five 15-minute exposures with a filter-modified (i.e. red sensitive) Canon 5D MkII camera at ISO 800. Stacking the images helps reduce noise.

The colours in this object make it particularly photogenic, with a contrast of magenta and cyan. At right, a sharp-edged area of obscuring interstellar dust tints the sky brown and dims the stars.

– Alan, October 9, 2013 / © 2013 Alan Dyer

The Cocoon Nebula in Cygnus


Cocoon Nebula IC 5146 (92mm 5DII)

A cocoon of glowing gas sits at the tip of a dark cloud of interstellar dust.

It’s been months since I’ve shot more “traditional” astrophotos, meaning images of deep-sky objects through telescopes. But the last couple of nights have been excellent, and well-timed to the dark of the Moon.

This is the Cocoon Nebula in Cygnus, aka IC 5146. It is a cloud of gas about 4,000 light years away where new stars are forming. They are lighting up the gas to glow with incandescent pink colours.

The Cocoon sits at the end of snake-like dark nebula known as Barnard 168 which, in the eyepiece of a telescope, is usually more obvious than the subtle bright nebula. Photos like mine here, with long exposures and boosted contrast and colours, make nebulas look much brighter and more colourful than they can ever appear to the eye.

For the technically curious, I shot this with a 92mm diameter apochromatic refractor, the TMB 92, and a Borg 0.85x flattener/reducer, a combination that gives a fast f-ratio of f/4.8 with a very flat wide field. I also used my now-vintage filter-modified Canon 5D MkII at ISO 800. This is a stack of five 12-minute exposures, registered and median-combined in Photoshop to smooth out noise. All processing was with Adobe Camera Raw and Photoshop CC. The telescope was on an Astro-Physics Mach 1 mount, flawlessly autoguided with an SBIG SG-4 autoguider.

– Alan, October 6, 2013 / © 2013 Alan Dyer

 

The Princess Stars


Andromeda (50mm 5DII)

The stars of Andromeda the Princess highlight the autumn sky.

Here’s an image from last night, October 4, that frames all of the constellation of Andromeda, now high in the northern autumn sky. A trio of coloured stars arcs across the centre of the image, forming the main pattern in Andromeda. In Greek legend she was the daughter of Queen Cassiopeia and was rescued by Perseus from the devouring jaws of Cetus the Sea Monster.

Above the centre star lies the constellation’s most famous feature, the Andromeda Galaxy, shining at us from 2.5 million light years away. It is the most distant object easily visible to the unaided eye.

An equal distance below the centre star of Andromeda you can see another smaller fuzzy spot. That’s the Pinwheel or Triangulum Galaxy, a dwarf spiral 2.8 million light years away, but also a member of the Local Group of galaxies that contains our Milky Way and Andromeda as its two main members.

At left, just below centre, is a large open cluster of stars, NGC 752, easily visible to the naked eye.

For this shot, as I do for most constellation portraits, I used Photoshop to layer in a shot taken through a diffusion filter (the Kenko Softon A) on top of a stack of shots taken without the filter. This allows me to add the enhanced glows around stars to bring out their colours, and to do so in a controlled fashion by varying the opacity of the filtered view. Shooting on a night with high haze or cirrus clouds has the same end effect but that’s hardly a reliable way to take constellation images. Combining filtered and unfiltered views works great, and gives the “look” made popular years ago by Japanese astrophotographer Akira Fuji.

– Alan, October 5, 2013 / © 2013 Alan Dyer

 

Star-Making Clouds in Cygnus


Cygnus Nebulosity (135mm 5DII)

The centre of Cygnus is laced with an intricate complex of glowing gas clouds.

This is another shot from earlier this week, under ideal skies, in a view looking straight up into Cygnus the Swan. This is a telephoto lens shot of the amazing array of nebulas in central Cygnus, around the bright star Deneb.

At left is the North America and Pelican Nebulas. At right is the Gamma Cygni complex and the little Crescent Nebula at lower right.

Here we’re looking down our local Cygnus-Orion arm of the Milky Way into a region of star formation rich in glowing hydrogen gas and dark interstellar dust. These clouds lie about 1500 to 3000 light years away. Dotting the field are hot blue stars newly formed from the raw ingredients making stars in Cygnus.

At top, the clouds have a lacework appearance, like sections of bubbles. Perhaps these are being blown across space by the high-velocity winds streaming from the young stars.

– Alan, September 13, 2013 / © 2013 Alan Dyer

 

A Galaxy Floating in the Void


M109 in Ursa Major (130mm 60Da)

A galaxy 80 million light years away floats in the blackness of space near a star in the Big Dipper.

This is Messier 109, a bright spiral galaxy in Ursa Major, and within an eyepiece and camera field of the bright naked eye star Gamma Ursa Majoris. That’s the “bottom left” star in the bowl of the Big Dipper, so this is an easy galaxy to find with a telescope in the current spring sky.

Technically, this galaxy is classed as a barred spiral because of the way its spiral arms emerge from an elongated bar at the core of the galaxy. It is the brightest member of the Ursa Major Cluster of some 80 galaxies.

Springtime is galaxy time, no matter what hemisphere you live in. But for us in the northern half of the planet that means April and May. When we look up at this time of year into the evening sky we are looking out of the plane of our Milky Way galaxy and seeing into the depths of intergalactic space, populated by thousands of other galaxies. Most of the bright ones, like M109, are 20 to 100 million light years away. At its distance of 80 million light years, M109 lies a million times farther away from us than Gamma Ursa Majoris, a nearby blue star “just” 80 light years away and in our Galaxy.

I shot this last weekend though my 5-inch refractor with the Canon 60Da camera. Even with the telescope’s 800mm focal length it isn’t enough to really do justice to the intricate detail in galaxies like this. But the view does set the galaxy into its context, floating in the blackness of space.

– Alan, May 11, 2013 / © 2013 Alan Dyer

Conjunction of Comet and Galaxy


Comet PANSTARRS & M31 (March 31, 2013)

Tonight, April 1, we enjoyed the rare conjunction of a comet with a galaxy.

This is Comet PANSTARRS below the Andromeda Galaxy, a.k.a. M31. The two objects were less than a binocular field apart – 4 degrees – on the sky. But in real space they were separated by millions of light years. The comet was 192 million kilometres from Earth tonight and receding. But that’s a stone’s throw compared to the 2.5 million light year distance of the Andromeda Galaxy. Light was taking a mere 10 minutes to get to us from the comet, but the light from Andromeda was 2.5 million years old.

And yet, the two objects looked similar in brightness and shape to the binocular-aided eye.

I caught the two just above the horizon as they were dipping into haze and trees. The circumstances didn’t make for a technically great photo but with PANSTARRS we’ve all had to shoot despite the conditions and hope for the best.

With worsening weather prospects for the next week I suspect this will be my last look at PANSTARRS for a while.

– Alan, April 1, 2013 / © 2013 Alan Dyer

 

 

The Zodiacal Light from the Desert


Zodiacal Light in Evening Sky (New Mexico)

From a dark site the glow of Zodiacal Light rivals the Milky Way in brightness. 

This was the scene every night last week in the evening sky from our New Mexico observing site. The vertical glow of Zodiacal Light was a source of natural light pollution brightening the western sky. I’ve never see it more obvious in the west and this was the perfect season to see it. In March from the northern hemisphere the ecliptic – the plane of the solar system – is angled high into the western sky, almost vertical from the latitude of southern New Mexico.

The Zodiacal Light lies not in our atmosphere but comes from interplanetary space, and follows the ecliptic. What we were seeing was a glow of sunlight being reflected off fine dust particles orbiting the Sun in the inner solar system, likely spread by passing comets like PANSTARRS. I blogged about the Zodiacal Light last month, in photo taken from home in southern Alberta. You can also read about it at the excellent Atmospheric Optics website.

You don’t need to be in the desert to see it, but you do need dark skies. And no Moon in the sky.

At last week’s dark of the Moon period, Jupiter sat at the apex of the Zodiacal Light, just above the Pleiades star cluster. Near the top, right of centre, you can also see a short satellite trail, likely from a flaring Iridium satellite.

– Alan, March 19, 2013 / © 2013 Alan Dyer

 

 

Skies of Enchantment – Winter Milky Way Setting


Winter Milky Way over Adobe House (14mm 5DII)

In the land of enchantment, the winter Milky Way sets over our adobe house.

I’m in New Mexico, enjoying wonderfully clear skies. In the early evening the winter Milky Way runs north and south then turns to set over in the west, as it’s doing here, over the main house at the Painted Pony Resort near Rodeo, in southwest New Mexico.

Jupiter and the stars of Taurus are at upper right, and Orion is just right of centre. Above the house shine Sirius and the stars of Canis Major and Puppis. The area of red in the Milky Way just above the house is the massive Gum Nebula in Vela, an area of sky hidden from us in Canada.

For this image I combined a stack of five 5-minute tracked exposures taken with the Canon 5D MkII at ISO 800 and 14mm Samyang lens wide open at f/2.8. The ground details are from two of the exposures.

This was a fabulous night with more to come this week.

– Alan, March 11, 2013 / © 2013 Alan Dyer

A Luminous Starfield


M38 & IC 405-410-417 Complex (92mm 6D)

The Starfish and the Flaming Star combine to create a rich star field in the Charioteer.

I shot this last week, using a favourite small refractor that takes in a generous field of view for a telescope. In this case, it frames the star cluster at left called the Starfish Cluster, or better known as Messier 38. At right the large number 7-shaped patch of nebulosity is the Flaming Star Nebula, known by its catalog number as IC 405. At bottom, the nameless companion nebulas are IC 417 at left and IC 410 at bottom centre.

Of note is the colourful grouping of six stars at right called the Little Fish. It’s not a proper star cluster but an asterism, a chance alignment of stars that happens to look like something imaginative. David Ratledge presents a nice list and photo gallery of similar whimsical asterisms at his Deep-Sky.co.uk website.

The entire field is a rich hunting ground for the eyepiece or camera. You can find it these nights, in winter from the northern hemisphere, straight overhead in the evening, in the middle of Auriga the Charioteer.

For this portrait I shot and stacked eight 7-minute exposures at ISO 800 using a filter-modified Canon 6D on my TMB 92mm apo refractor at f/4.8.

Happy Valentine’s Day!

– Alan, February 14, 2013 / © 2013 Alan Dyer

 

See, That’s the Orion Nebula!


RAO Open House (February 9, 2013)

What a hardy bunch we are in Canada, braving winter weather to see Orion and company. 

A well-bundled group of sky fans partakes in an impromptu tour of Orion and his famous nebula.

I shot this scene last night, February 9, at the first of a series of monthly stargazing nights at the local university research observatory, the Rothney Astrophysical Observatory. About 120 people and volunteers gathered to take in the sights of the winter sky, as best they could as transient clouds permitted. Inside, speakers presented talks themed to the Chinese New Year, which is governed by the timing of the New Moon each year. As this was a New Moon night, people were able to stargaze under reasonably dark skies to see deep-sky sights such as the Orion Nebula.

Want to know where it is? An astronomy club member points it out rather handily with one of the best tools astronomers have for public outreach, a bright green laser pointer. Controversial and dangerous in the wrong hands, when used responsibly these laser pointers are wonderful for conducting sky tours.

As a side note, this is a 3-second exposure with a new Canon 6D camera at ISO 8000, yet the photo shows very little noise. In just 3 seconds, the Milky Way is beginning to show up! I could have gone to previously unthinkable speeds of ISO 12000+ and still had a presentable shot. This will be a superb camera for nightscapes and available light shots.

– Alan, February 10, 2013 / © 2013 Alan Dyer

 

The Beautiful Belt of Orion


Belt of Orion & B33 Horsehead Nebula (92mm 6D)

Everyone knows the Belt of Orion, but only the camera reveals the wealth of colours that surround it.

I shot this Friday night, February 8, under very clear sky conditions.

While I used a telescope, it had a short enough focal length, about 480mm, that the field took in all three stars in the Belt: from left to right, Alnitak, Alnilam, and Mintaka. All are hot blue stars embedded in colourful clouds. The most famous is the Horsehead Nebula, running down from Alnitak at left. Above the star is the salmon-coloured Flame Nebula. All manner of bits of blue and cyan nebulas dot the field, their colour coming from the blue starlight the dust reflects.

Dimmer dust clouds more removed from nearby stars glow with browns and yellows. At left, a large swath of sky is obscured by gas and dust simmering in dull red. The entire field is peppered with young blue stars.

It is certainly one of the most vibrant regions of sky, though only long exposures and image processing bring out the colours.

This is another test shot with a new Canon 6D that has had its sensor filter modified to transmit more of the deep red light of these types of nebulas. The camera works very well indeed!

– Alan, February 8, 2013 / © 2013 Alan Dyer

Snapshots of Starlife


IC 443 Jellyfish Nebula & M35 (92mm 6D)

This one image frames examples of both the beginning and end points of a star’s life.

I shot this last night, February 6, 2013, capturing a field in the constellation of Gemini the twins. At upper right is the showpiece star cluster known as Messier 35. It’s a collection of fairly young stars still hanging around together after forming from a cloud of interstellar gas tens of millions of years ago. M35 lies about 2,800 light years from Earth, on the other side of the spiral arm we live in. Just below M35 you can see another smaller and denser cluster. That’s NGC 2158, about five times farther away from us, thus its smaller apparent size. Both are objects that represent the early stages of a star’s life.

At lower left is an object known as the Jellyfish Nebula, for obvious reasons. The official name is IC 443. It’s the expanding remains of a star that blew up as a supernova anywhere from 3,000 to 30,000 years ago. What’s left of the star’s core can still be detected as a spinning neutron star. You need a radio telescope to see that object, but the blasted remains of the star’s outer layers can be seen through a large backyard telescope as a shell of gas. It is expanding into the space between stars – the interstellar medium – ploughing into other gas clouds. The shockwave from its collision with other nebulas may trigger those clouds to collapse and form clusters of new stars. And so it goes in the Galaxy.

For this portrait of stellar lifestyles, I used a 92mm apochromatic refractor and a new Canon 6D camera, one that has had its sensor filter modified to accept a greater range of deep red light emitted by hydrogen nebulas. The image is actually a stack of 12 exposures with an accumulated exposure time of 80 minutes.

– Alan, February 7, 2013 / © 2013 Alan Dyer

Constellation of the Queen


Cassiopeia (135mm 5DII)

After the 7 stars of the Big Dipper and the 3 stars of Orion’s Belt, these 5 stars are likely the most well-known in the northern sky.

These are the 5 bright stars of Cassiopeia the queen, better known simply as “the W” in the sky. Her five stars come in a range of colours, from blue giant Segin at upper left to yellow giant Shedar at lower right.

Scattered around Cassiopeia you can also spot at least one bright red nebula, the “Pacman Nebula,” plus a faint patch of purple nebulosity just above central Navi, the middle star of the W also known as Gamma Cassiopeiae. A few wisps of fainter reddish nebulosity and lanes of dark dust wind around the queen’s celestial throne. The left side of the W – the back of the throne –  is also home to several clumps of stars, nice open clusters suitable for binoculars or any telescope.

I shot this portrait of the Queen on Wednesday night, February 6, on a cool and frosty winter night in my backyard. For the set of 8 images that went into this stack I used a new tracking device, the iOptron SkyTracker. It’s a nifty little battery-powered tracker, compact but very solid. And it tracks very well. For this portrait I used a 135mm telephoto lens, and most, though not all, shots were very well tracked with pinpoint stars. A few frames showed a bit of trailing, not unusual for small portable tracking mounts. At $400 the little iOptron SkyTracker is a great accessory for anyone wanting to shoot constellations and the Milky Way with wide-angle to telephoto lenses.

– Alan, February 7, 2013 / © 2013 Alan Dyer

The Natural Naked-Eye Milky Way


Centre of the Milky Way Panorama (2011)

In this image I’ve tried to render the Milky Way in a view that simulates what you see with your unaided eyes.

The result is a celestial portrait in subtle shades of black and white.

This is a photo mosaic, but processed contrary to the usual methods – eliminating colour rather than enhancing it, and reducing contrast rather than boosting it. The result is a view that I think quite nicely matches what your eyes see, though certainly from a dark site. And in this case, you would need to be in the southern hemisphere to see this sweep of the Milky Way, from Aquila at left, to the Southern Cross at right, with the bright star clouds around the centre of the Galaxy in Sagittarius and Scorpius in the middle.

I’ve removed colours except for the muted colours of stars. And I’ve tried to render the stars with an intensity and dynamic range that the eye sees but that is often lost in long exposures.

The dark lanes of dust seen here really do look like this under dark skies. The nearby Coal Sack next to the Southern Cross does look a little darker than the rest of the sky. This view also captures another effect you can see in the real sky – the brighter sky below the Milky Way plane beneath Sagittarius and Aquila – there are more stars there, which make the background sky brighter than above the Milky Way plane (along the top of the photo) where the sky is permeated by dark obscuring dust.

This scene also frames the “dark Emu” – the shape drawn in the dark lanes that looks like a flightless emu in the sky. It’s an important “constellation” in Aboriginal mythology in Australia. The emu’s head is the Coal Sack at far right, her neck the long dark lane curving up through Centaurus and Lupus, and her tail the dark lanes at left in Ophiuchus, Scutum and Aquila.

I shot the original images for this panoramic mosaic in Chile in May 2011. You can see the full colour version in my “Milky Way Mosaic” post from 2011. The colours are wonderful. But there’s something enthralling about “capturing” the view more as your eyes – and mind – remember it.

– Alan, February 3, 2013 / © 2013 Alan Dyer

An Orion Portrait from Alberta


Orion in Porttrait Format

He’s certainly the sky’s most photogenic mythological figure. Here’s my full-length portrait of Orion the hunter, captured from Alberta.

I’ve shot him many times before but this was a new combination of gear: the Canon 60Da camera and the Sigma 50mm lens, nicely framing the hunter in portrait format. This version of Orion isn’t as deep as the one I took last month from Australia. But skies were darker there, and I used my filter-modified Canon 5D MkII for his Oz portrait, a camera which picks up more faint red nebulosity than does the 60Da, Canon’s own specialized DSLR camera for astronomy. The 60Da does do a very good job though, much better than would a normal DSLR.

For this shot, as I do for many constellation images, I layered in exposures taken through a soft-focus filter, the Kenko Softon, to enlarge and “fuzzify” the stars! It really helps bring out their colours, contrasting cool, orange Betelgeuse with the hot blue-white stars in the rest of Orion.

I shot this January 4 on a fine clear winter night, the classic hunting ground for Orion.

– Alan, January 11, 2013 / © 2013 Alan Dyer

Winter Stars Rising


The Winter Sky, Northern Hemisphere

Yes, it’s cold out there, but a clear evening away from city lights this week – or this winter – will reward you with the sight of a rising star-filled sky.

This is the winter sky of the northern hemisphere, rising above a snowy prairie landscape, in a shot I took Sunday night, January 6, 2013. The sky is populated by a ream of bright stars and constellations, anchored by Orion, just below centre. You can see his three Belt stars pointing down to Sirius, just peering above the horizon in the glow of a distant town. Orion’s Belt points up to Aldebaran, the V-shaped Hyades star cluster, and bright Jupiter (the brightest object in the scene, above centre), all in Taurus. Above Jupiter is the Pleiades star cluster.

The Milky Way runs down the sky from Auriga to Canis Major. This week, January 6 to 13, is a good week to see the winter Milky Way, as it’s New Moon and the sky is dark.

In this scene the camera was looking southeast about 9 p.m. Sirius has just risen. By midnight the Dog Star shines due south. I used a 15mm wide-angle lens to take in the entire sweep of the winter sky from horizon to zenith. This is a stack of four 4-minute exposures, though the landscape is from just one of the frames, to minimize the blurring caused by the camera tracking the sky. Some clouds moving in add the streaks on either side of the frame. It was a wonderful sky, while it lasted!

And I’m pleased to note that this is my 250th blog post since beginning AmazingSky.net two years ago in early 2011. I hope you have enjoyed the sky tours.

– Alan, January 6, 2013 / © 2013 Alan Dyer

Jupiter Amid the Clusters of Taurus


Jupiter in Taurus (January 4, 2013)

Look up on a clear night this season (winter for us in the northern hemisphere) and you’ll see a bright object shining in Taurus the bull. That’s Jupiter.

This year Jupiter sits in a photogenic region of the sky, directly above the stars of the Hyades star cluster and yellow Aldebaran, the brightest star in Taurus. Above and to the west (right) of Jupiter is the blue Pleiades star cluster.

Over the course of January 2013 you’ll be able to see Jupiter move a little further west each night (to the right in this photo) away from Aldebaran and toward the Pleiades. Jupiter will stop its retrograde motion on January 30. After that it treks eastward to again pass above the Hyades and Aldebaran (returning to where it is now) in early March.

Jupiter’s proximity to Aldebaran and the Hyades makes it easy to follow its retrograde loop over the next few weeks. It’s an easy phenomenon to watch, but explaining it took society hundreds of years and the ultimate in paradigm shifts in thinking, from the self-important arrogance that Earth – and we – were the centre of the universe, to the Sun-centered view of space, with Earth demoted to being just one planet orbiting our star.

I took this image Friday night, January 4, from home as my first astrophoto upon returning to Canada from Australia. It’s a combination of two sets of images: one taken “straight & unfiltered” and one taken through a soft-focus filter to add the glows around the stars and central, brilliant Jupiter. I then blended the filtered images onto the normal images in Photoshop with the Lighten blend mode.

– Alan, January 5, 2013 / © 2013 Alan Dyer

A Truly Amazing Sky — A New Year’s Gift


Timor Cottage Panorama #3

As we end 2012 and start a new year, I wish everyone a very happy 2013 and leave you with this view of a very amazing sky.

This is a 360° panorama of the Milky Way over Timor Cottage on a very clear night in mid-December in New South Wales, Australia. May all your skies be as wonderful and as inspiring as this in the coming year.

Indeed, we have some potentially remarkable sights to look forward to, with the prospects of two bright comets in 2013: Comet PANSTARRS in March and Comet ISON in November and December.

Let’s hope for more amazing skies in 2013. Keep looking up!

– Alan, December 31, 2012 / © 2012 Alan Dyer

Zooming into Canis Major – #3


NGC 2359 Thor's Helmet NebulaIn the third instalment in my trilogy of Canis Major zooms, I present this close-up of another neat nebula in the Great Hunting Dog, called Thor’s Helmet.

You can tell just by the colour that this is a different type of nebula than the typical red hydrogen gas clouds, such as the Seagull Nebula of my previous post. Yes, this is glowing gas but this nebula originates from a different source than most. Rather than being a site where stars form this is a nebula surrounding an aging star, a massive superhot star that is shedding shells of gas in an effort to lose weight – or mass as we should say.

Intense winds from the star blow the gas into bubbles, and cause it to fluoresce in shades of cyan. The central star is one of a rare stellar type called a Wolf-Rayet star, named for the pair of French astronomers who discovered this class of star in the 19th century. WR stars are likely candidates to explode as supernovas.

This particular Wolf-Rayet nebula, catalogued as NGC 2359, has a complex set of intersecting bubbles that, through the eyepiece, do take on the appearance of a Viking helmet with protruding horns, like you see in the Bugs Bunny cartoon operas! It’s a neat object to look at with as big a telescope as you can muster. And, as you can see, it’s rather photogenic as well, embedded in a rich field with faint star cluster companions.

– Alan, December 28, 2012 / © 2012 Alan Dyer

Zooming into Canis Major – #2


IC 2177 Seagull Nebula Complex

Zooming in closer yet again to the field in Canis Major I showed in my previous post, I’m now framing the large nebula known as the Seagull. Perhaps you can see him flying through the stars.

The catalog number for this object is IC 2177, but the bright round nebula at right (the head of the Seagull?) is object #1 in the catalog of Australian astronomer Colin Gum. It’s also object #2327 in the familiar NGC listing that all stargazers use.

Some of this nebulosity is just visible through a small telescope, especially with the aid of a nebula filter than accentuates the emission lines – the colours – emitted by these kinds of glowing gas clouds.

This is certainly a photogenic field, with a nice mix of pinks, blues, purples and deep reds.

I used my 4-inch (105mm aperture) f/5.8 apo refractor to shoot this target, so the field is fairly narrow, framing what a telescope would show at very low power.

(FYI – The image info listed at left, automatically picked off the image’s EXIF data by the WordPress blog software, fails to record the focal length of the optics properly, as I didn’t use a standard camera lens but a telescope the camera doesn’t know about.)

I’ve been after a good shot of this object for some years, but haven’t been successful until this past observing run in Australia, in December 2012. While I can see and shoot the Seagull Nebula from home in Alberta, it’s always very low in my home sky. From Australia the challenge was framing the field with the Seagull overhead at the zenith. Just looking through the camera aimed straight up took some ground grovelling effort. Plus avoiding having the telescope hit the tripod as it tracked the object over the hour or so worth of exposures – typically 4 to 5 that I then stack to reduce noise.

– Alan, December 28, 2012 / © 2012 Alan Dyer

 

Zooming into Canis Major – #1


M50 - M46/M47 Area Bino Field

My last post featured a wide view of Canis Major. Here, we zoom in closer to one of the most interesting regions in that constellation, filled with nebulas and clusters.

The prominent red arc is the Seagull Nebula, aka IC 2177. Above and to the right of the Seagull is a clump of stars called Messier 50, which lies over the border in the constellation of Monoceros the Unicorn.

At the lower left edge of the frame sits a pair of dissimilar star clusters, Messier 46 (the left one) and Messier 47 (the right one). M46 is a dense rich cluster of stars while M47 is brighter but looser and more scattered.

Several other non-Messier clusters punctuate the field. This is a great area of sky to explore with binoculars.

Just below centre you might see a small green-blue patch. That’s the nebula called Thor’s Helmet, or NGC 2359, a fine telescopic object.

If you get a clear night this season when the Moon is out of the way and you can head to a dark sky, Canis Major, the Hunting Dog, is a great hunting ground for deep-sky fans.

As the data at left shows, I shot this with a 135mm telephoto lens, giving a field of view similar to what binoculars would show.

– Alan, December 28, 2012 / © 2012 Alan Dyer

Canis Major and the Dog Star


Canis Major from Australia (50mm 5DII)

Shining in the southern sky these nights are the stars of Canis Major, the big hunting dog of Orion the Hunter. Among them is the famous Dog Star, Sirius, the brightest star in the night sky.

Can you see a dog outlined in stars? Sirius marks his head – or it is sometimes depicted as a jewel in his collar. His hind legs and tail are at the bottom of the frame.

I shot this earlier this month from Australia, where Sirius and Canis Major stand high overhead. From northern latitudes you can see these stars due south low in the sky about midnight. Sirius is hard to miss, often sparkling through many colours as our atmosphere distorts its light. But as the photo shows, it is really a hot blue-white star. While it is intrinsically a bright star, much of its brilliance in our sky comes from its proximity, only 9 light years away from us.

For this portrait of the celestial canine I used a 50mm “normal” lens. The atmosphere provided some natural haze this night, to add the glows around the stars accentuating their colours.

This area of sky also contains several nebulas, notably the red arc of the Seagull Nebula to the left of Sirius. Below Sirius you can also see the star cluster Messier 41, a good target for binoculars.

Toward the left edge of the frame you can see a pair of star clusters, Messier 46 and Messier 47, two other excellent binocular objects in the Milky Way, which runs down the frame to the left of Canis Major. The dog is just climbing out of the Milky Way after a swim in this river of stars.

– Alan, December 28, 2012 / © 2012 Alan Dyer

 

The Christmas Tree Cluster


NGC 2264 Christmas Tree Cluster & Cone Nebula

 

The current night sky contains another seasonal sight, a cluster of stars called the Christmas Tree Cluster. Turn the image upside down and you might see it!

The bright star lies at the base of the Christmas tree and at the bottom of a tall triangle of blue and yellow stars that outlines – or decorates – the tree. At the top of the tree sits the dark Cone Nebula. The Tree also encompasses a bright blue dusty nebula reflecting the light of nearby stars and swirls of pink glowing hydrogen. At right sits a rich cluster of stars dimmed yellow by intervening dust. At bottom (south) in this photo you can also see a small V-shaped object. That’s Hubble’s Variable Nebula, a dust cloud studied by Edwin Hubble, one that varies in intensity with fluctuations in the main star embedded at its tip.

This rich area of sky lies above (north of) the subject of my previous post, the Rosette Nebula in the constellation of Monoceros the Unicorn. Very little of this is visible to the eye. The magic of photography is how it coaxes detail out of the sky that the eye alone cannot see.

– Alan, December 27, 2012 / © 2012 Alan Dyer

 

A Cosmic Wreath in the Sky


NGC 2237 Rosette Nebula

This is the Rosette Nebula, a celestial wreath 5,000 light years in the northern winter sky.

It is one of the most photogenic of nebulas, but is barely visible to even an aided eye as a ghostly grey arc of light around the central star cluster. Winds from the group of hot stars at the centre of the Rosette are blowing a hole in the cloud, creating the wreath-like shape of the Rosette.

While I shot this earlier this month from Australia, the Rosette lies far enough north in the constellation of Monoceros that northerners can see this cosmic wreath on any dark and clear winter night. It makes a beautiful decoration in our holiday sky.

Happy holidays to all!

– Alan, December 26, 2012 / © 2012 Alan Dyer

The Colourful Clouds of Orion – #2


The Nebulas of Orion v2

Swirls of pink, red and blue nebulas surround the Belt and Sword of Orion the Hunter.

For this closeup of Orion I used a 135mm telephoto lens under dark Australian skies to grab long exposures to reveal not only the bright Orion Nebula at bottom in Orion’s Sword, but also the Horsehead Nebula (below the left star of Orion’s Belt), Barnard’s Loop (at left) and the mass of red nebulosity between the Loop and the Belt & Sword. At right is a faint blue nebula reflecting the light of the hot blue stars in the area.

This is a gorgeous area of sky for the camera, but only the brightest nebulas, the tip of the cosmic iceberg, are visible to the eye even with the aid of a telescope.

– Alan, December 19, 2012 / © 2012 Alan Dyer

 

The Colourful Clouds of Orion – #1


Orion from Australia (50mm 5DII)

The constellation Orion is a hotbed of star formation, from masses of colourful clouds.

I shot this portrait of Orion the Hunter a few nights ago in Australia where Orion stands upside down compared to our view from up north. But I’ve turned around the photo here to put him right side up with head at the top and feet at the bottom.

The three stars in a row in the middle are his famous Belt stars. Below shines the nebulas that outline his Sword, among them the Orion Nebula, the subject of an earlier post last week

The giant arc is Barnard’s Loop, a bubble blown in space by the winds from hot new stars. The bubble around Orion’s head at top is a similar interstellar bubble. Most stars here are blue-white and hot, but the distinctively orange star is the red giant Betelgeuse, a good candidate for a supernova explosion.

Orion stands high in the sky at midnight these nights, summer here in Australia, but winter at home in Canada.

– Alan, December 19, 2012 / © 2012 Alan Dyer

 

Remains of a Star: The Vela Supernova Remnant


Vela Supernova Remnant and Gum Nebulas

Amid a maze of glowing nebulas sits a tracery of magenta and cyan that was once a star.

This image takes in the Vela Supernova Remnant. You can see it as the lacework of gas in the centre of the field. Oddly enough, it sits in the middle of the vast Gum Nebula, the subject of my previous post, an object also thought to be a supernova remnant but one much older and closer. The Vela Supernova Remnant here likely comes from a supergiant star that exploded about 10,000 years ago. It, too, would have been quite a sight to the earliest of civilizations.

The field in the southern constellation of Vela also contains many other classic red and pink nebulas, but ones that are forming new stars, not the remains of dead ones. Most carry designations from astronomer Colin Gum’s catalog from the 1950s and have no numbers from the more familiar NGC or IC catalogs amateur stargazers refer to in their scanning of the skies. Yet, these Gum nebulas show up easily in photos.

I used a 135mm telephoto lens to take this image and it encompasses a field similar to what binoculars would frame. Except, it takes long exposure photos to show these nebulas. I looked last night at the Vela SNR with my 25cm reflector telescope and could just barely see the main arc of nebulosity as a grey ghost in the eyepiece. And that was under perfect dark Australian sky conditions.

– Alan, December 18, 2012 / © 2012 Alan Dyer