Canon vs. Nikon for Astrophotography


Canon and Nikon Cameras

I’ve been an avowed Canon DSLR user for a decade. I may be ready to switch!

This is a decidedly non-pretty-picture blog!

Here, in a technical blog, I present my tests of two leading contenders for the best DSLR camera for nightscape and astronomical photography: the Canon 6D vs. the Nikon D750. Which is better?

To answer, I subjected both to side-by-side outdoor tests, using exposures you’ll actually use in the field for typical nightscapes and for deep-sky images.

Both cameras are stock, off-the-shelf models. They have not had their filters modified for astronomy use. Both are 20- to 24-megapixel, full-frame cameras, roughly competitive in price ($1,900 to $2,300).

For images shot through lenses, I used the Canon L-Series 24mm on the Canon 6D, and the Sigma 24mm Art lens on the Nikon D750.

The bottom line: Both are great cameras, with the Nikon D750 having the edge for nightscape work, and the Canon 6D the edge for deep-sky exposures.

NOTE: Click on the test images for higher-resolution versions for closer inspection. All images and text © 2015 Alan Dyer and may not be reproduced without my permission.


TEST #1 — Noise

The 24.3-megapixel Nikon D750 has 5.9-micron pixels, while the 20.2-megapixel Canon 6D has slightly larger 6.5-micron pixels which, in theory, should lead to lower noise for the Canon. How do they compare in practice?

The scene used to test for noise (here with the Nikon images) showing the development settings applied to both the Nikon and Canon sets. NO noise reduction (colour or lunminance) was applied to any of the images, but Exposure, Shadows, Contrast and Clarity were boosted, and Highlights reduced.
The scene used to test for noise (here with the Nikon images) showing the development settings applied to both the Nikon and Canon sets. NO noise reduction (colour or lunminance) was applied to any of the images, but Exposure, Shadows, Contrast and Clarity were boosted, and Highlights reduced.

I shot a moonlit nightscape scene (above) at five ISO settings, from 800 to 12800, at increasingly shorter exposures to yield identically exposed frames. I processed each frame as shown above, with boosts to shadows, clarity, and contrast typical for nightscapes. However, I applied no noise reduction (either luminance or color) in processing. Nor did I take and apply dark frames.

Noise - Canon

Noise - Nikon

The blowups of a small section of the frame (outlined in the box in the upper right of the Photoshop screen) show very similar levels of luminance noise. The Canon shows slightly more color noise, in particular more magenta pixels in the shadows at high ISOs. Its larger pixels didn’t provide the expected noise benefit.


TEST #2 — Resolution

Much has been written about the merits of Canon vs. Nikon re: the most rigorous of tests, resolving stars down at the pixel level.

I shot the images below of the Andromeda Galaxy the same night through a 92mm aperture apo refractor. They have had minimal but equal levels of processing applied. At this level of inspection the cameras look identical.

M31 (Canon 6D)

M31 (Nikon D750)

But what if we zoom in?

For many years Nikon DSLRs had a reputation for not being a suitable for stellar photography because of a built-in noise smoothing that affected even Raw files, eliminating tiny stars along with noise. Raw files weren’t raw. Owners worked around this by turning on Long Exposure Noise Reduction, then when LENR kicked in after an exposure, they would manually turn off the camera power.

This so-called “Mode 3” operation yielded a raw frame without the noise smoothing applied. Clearly, this clumsy workaround made it impossible to automate the acquisition of raw image sequences with Nikons.

Are Nikons still handicapped? In examining deep-sky images at the pixel-peeping level (below), I saw absolutely no difference in resolution or the ability to record tiny and faint stars. With its 4-megapixel advantage the Nikon should resolve finer details and smaller stars, but in practice I saw little difference.

Closeup of telescope view of Andromeda Galaxy with Canon 6D 4 minute exposure at ISO 800 No noise reduction applied in processing
Closeup of telescope view of Andromeda Galaxy with Canon 6D
4 minute exposure at ISO 800
No noise reduction applied in processing
Closeup of telescope view of Andromeda Galaxy with Nikon D750 4 minute exposure at ISO 800 No noise reduction applied in processing
Closeup of telescope view of Andromeda Galaxy with Nikon D750
4 minute exposure at ISO 800
No noise reduction applied in processing

On the other hand I saw no evidence for Nikon’s “star eater” reputation. I think it is time to lay this bugbear of Nikons to rest. The Nikon D750 proved to be just as sharp as the Canon 6D.

Note that in the closeups above, the red area marks a highlight (the galaxy core) that is overexposed and clipped. Nikon DSLRs also have a reputation for having sensors with a larger dynamic range than Canon, allowing better recording of highlights before clipping sets in.

However, in practice I saw very little difference in dynamic range between the two cameras. Both clipped at the same points and to the same degree.


TEST #3 — Mirror Box Shadowing

An issue little known outside of astrophotography is that a DSLR’s deeply-inset sensor can be shadowed by the upraised mirror and sides of the mirror box. Less light falls on the edges of the sensor.

The vignetting effect is noticeable only when we boost the contrast to the high degree demanded by deep-sky images, and when shooting through fast telescope systems.

Here I show the vignetting of the Canon and Nikon when shooting through my 92mm refractor at f/4.5.

The circular corner vignetting visible in the images below is from the field flattener/reducer I employed on the telescope. It can be compensated for by using Lens Correction in Adobe Camera Raw, or eliminated by taking flat fields.

Demonstrating the level of vignetting and mirror-box shadowing with the Canon 6D on a TMB 92mm apo refractor with a 0,85x field flattener/reducer lens
Demonstrating the level of vignetting and mirror-box shadowing with the Canon 6D on a TMB 92mm apo refractor with a 0.85x field flattener/reducer lens
Demonstrating the level of vignetting and mirror-box shadowing with the Nikon D750 on a TMB 92mm apo refractor with a 0,85x field flattener/reducer lens
Demonstrating the level of vignetting and mirror-box shadowing with the Nikon D750 on a TMB 92mm apo refractor with a 0.85x field flattener/reducer lens

The dark edge at the bottom of the frame is from shadowing by the upraised mirror. It can be eliminated only by taking flat fields, or reduced by using masked brightness adjustments in processing.

Both cameras showed similar levels of vignetting, with the Canon perhaps having the slight edge.


TEST #4 — ISO Invariancy

So far the Nikon D750 and Canon 6D are coming up fairly equal in performance. But not here. This is where the Nikon outperforms the Canon by quite a wide margin.

Sony sensors (used in Sony cameras and also used by Nikon) have a reputation for being “ISO Invariant.”

What does that mean?

A typical Milky Way nightscape with the Nikon D750 and Sigma 24mm Art lens. With no Moon, shot at very high ISO of 6400 and wide aperture of f/1.4 to show image quality under these demanding shooting circumstances. Lens correction and basic development setttings applied.
A typical Milky Way nightscape with the Nikon D750 and Sigma 24mm Art lens.
With no Moon, shot at very high ISO of 6400 and wide aperture of f/1.4 to show image quality under these demanding shooting circumstances.
Lens correction and basic development setttings applied.
A typical Milky Way nightscape with the Canon 6D and Canon 24mm L lens (original model). With no Moon, shot at very high ISO of 6400 and wide aperture of f/1.4 to show image quality under these demanding shooting circumstances. Lens correction and basic development setttings applied.
A typical Milky Way nightscape with the Canon 6D and Canon 24mm L lens (original model).
With no Moon, shot at very high ISO of 6400 and wide aperture of f/1.4 to show image quality under these demanding shooting circumstances.
Lens correction and basic development setttings applied.

In the examples above, the correct exposure for the starlit scene was 15 seconds at f/1.4 at ISO 6400. See how the two cameras rendered the scene? Very similar, albeit with the Canon showing more noise and discoloration in the dark frame corners.

What if we shoot at the same 15 seconds at f/1.4 … but at ISO 3200, 1600, 800, and 400? These are now 1-, 2-, 3-, and 4-stops underexposed, respectively.

Then we boost the Exposure setting of the underexposed Raw files later in processing, by 1, 2, 3 or 4 f-stops. What do we see?

Nikon D750 - Comparing ISO Invariancy from ISO 6400 to 400 (Nightscape)
Nikon D750 – Comparing ISO Invariancy from ISO 6400 to 400 (Nightscape)

With the Nikon (above) we see images that look nearly identical for noise to what we got with the properly exposed ISO 6400 original. It really didn’t matter what ISO speed the image was shot at – we can turn it into any ISO we want later with little penalty.

Canon 6D - Comparing ISO Invariancy from ISO 6400 to 400 (Nightscape)
Canon 6D – Comparing ISO Invariancy from ISO 6400 to 400 (Nightscape)

With the Canon (above) we get images with grossly worse noise in the shadows and with ugly magenta discoloration. Canons cannot be underexposed. You must use as high an ISO as needed for the correct exposure.

This “ISO Invariant” advantage of Nikon over Canon is especially noticeable in nightscapes scenes lit only by starlight, as above. The Canon turns ugly purple at -3EV underexposure, and loses all detail and contrast at -4EV underexposure.

For nightscape imaging this is an important consideration. We are limited in exposure time and aperture, and so are often working at the ragged edge of exposure. Dark areas of a scene are often underexposed and prone to noise. With the Nikon D750 these areas may still look noisy, but not much more so than they would be at that ISO speed.

With the Canon 6D, underexpose the shadows and you pay the price of increased noise and discoloration when you try to recover details in the shadows.

NOTE: In case you think this difference arises only because of the lens, not the camera or sensor, I invite you to check the version of this review at my website page, where there are images taken with each camera shooting through the same optics, the telescope. They show the same difference due to the “ISO invariant” sensor in the Nikon vs. the “ISO variant” sensor in the Canon. 

For more technical information on the topic of ISO invariancy, see DPReview.com and many of their recent reviews of DSLRs, such as this page about the Canon 5Ds/r models. 

Apparently, the difference comes from where the manufacturer places the analog-to-digital circuitry: on the sensor (ISO invariant) or outboard on a separate circuit (ISO variant), and thus where in the signal path the amplification occurs when we boost ISO speed.


TEST #6 — Features

One could go on endlessly about features, but here I compare the two cameras on just a few key operating features very important to astrophotographers.

Nikon Intervalometer Start

Intervalometer:

The Canon 6D has none, though newer Canons do. The Nikon D750, as do many Nikons, has a built-in intervalometer (shown above), even with a deflickering “Exposure Smoothing” option. However, exposure time is limited to the camera’s maximum of 30 seconds. Any longer requires an outboard intervalometer, as with the Canon.

If you use your camera with any motion control time-lapse unit, then it becomes the intervalometer, negating any capability built into the camera. But it’s nice to have.

Small Advantage: Nikon


Interval Length:

When taking time-lapse or star trail images with the Canon I can set an interval as short as 1 second between frames, for a minimum of gaps or jumps in the stars. With the Nikon, depending on whether it is controlled internally or externally, and on the length of exposure, the interval usually has to be no less than 3 to 4 seconds, which can lead to unsightly gaps in star trails.

Small Advantage: Canon


Nikon D750 with Radian

Tiltable LCD Screen:

The Canon 6D has none. The Nikon D750 has a very useful tilt-out screen as shown above. This is hugely convenient for all forms of astrophotography. Only cropped-frame Canons have tilt-out screens. This feature might add weight, but it’s worth it!

Big Advantage: Nikon


Dark Frame Buffer:

The Nikon has none. With Long Exposure Noise Reduction ON, the Canon 6D allows up to four exposures to be shot in quick succession before the dark frame kicks in and locks up the camera. (Put the camera into Raw+JPG.)

This is very useful for deep-sky imaging, for acquiring a set of images for stacking that have each had a dark frame subtracted in-camera, with a minimum of “down-time” at the camera.

Big Advantage: Canon


Live View Screen Brightness:

As pointed out to me by colleague Christoph Malin, with the Nikon you cannot dim the screen when in Live View mode and with Exposure Simulation ON. So it can be too bright at night. With the Canon you can dim the Live View screen — the LCD Brightness control affects the screen both during Live View as well as during playback of images.

Small Advantage: Canon


Canon with GBTimelapse

Software Compatibility:

Canon EOS cameras are well supported by advanced software, such as GBTimelapse (above) that controls only Canons, not Nikons, in complex time-lapse sequences, and Nebulosity, popular among deep-sky imagers for DSLR control.

Small Advantage: Canon


My take-away conclusions: 

• Nikon DSLRs now are just as good for astrophotography as Canons, though that wasn’t always the case – early models did suffer from more noise and image artifacts than their Canon counterparts.

• Canon DSLRs, due to their sensor design, are more prone to exhibiting noise and image artifacts when images are greatly underexposed then boosted later in processing. Just don’t underexpose them – good advice for any camera.


You can read a slightly more complete version of this report at my website at

http://www.amazingsky.com/canon-vs-nikon.html

… where you can also download higher resolution versions of the test images for closer inspection.

My website version contains test images of the ISO Invariance difference on images of the Andromeda Galaxy, as well as comparison images of the Canon 24mm L-series lens vs. the Sigma 24mm Art lens.

All images and text are © 2015 Alan Dyer.

– Alan, August 27, 2015 & Revised August 28, 2015 / © 2015 Alan Dyer / www.amazingsky.com

Time and Tide … and the Pull of the Moon


Sunset at Point Prim Lighthouse, near Digby, Nova Scotia on the Fundy side of the peninsula, with a waxing crescent Moon in the western twilight sky. The dark rocks are basaltic volcanic rocks from the late Triassic formed as part of the rifting that split Gondwonaland into the Americas and Europe and Africa. The Lighthouse is the fourth in a succession of lighthouses built at Point Prim starting in 1804. It was automated in 1984. This is a panorama created from 9 segments taken with the 16-35mm lens at 35mm and Canon 6D. Stitched in Photoshop.

Nothing demonstrates the power of the sky to affect the Earth better than the daily ebb and flow of the tides.

For a few days earlier this week I was fortunate to visit Nova Scotia, to speak at the annual Nova East Star Party.

A scene at the Nova East Star Party near Windsor, Nova Scotia, in August 2015, showing laser pointer in use under a clear starry sky.
A scene at the Nova East Star Party near Windsor, Nova Scotia, in August 2015.
I took advantage of my visit to Canada’s east coast to shoot time-lapses of one of nature’s most amazing phenomena, the daily pulse of the tides.

The coastal regions around the Bay of Fundy, particularly on the Nova Scotia shore, and around the Minas Basin, experience the highest tides in the world. The range can be as much as 16 metres. Only remote Leaf Basin on Ungava Bay in northern Québec matches the Minas Basin for tidal range.

The reason is not, as is sometimes stated, the funnel shape of the Bay of Fundy, but rather its length. It takes about 12 hours and 25 minutes for an ocean wave to traverse the length of the Bay, equal to the time between successive high tides. This creates a resonance, with the incoming and outgoing waves building upon each other and increasing the height of the twice-a-day tides.

The amount of water moving back and forth is mind-boggling: some 9 to 16 billion tonnes of water flows daily into and out of the Minas Basin alone, enough to tilt the land.

For the time-lapse videos I shot at two locations:

  • Evangeline Beach on Minas Basin, with vast tidal flats that are engulfed twice a day.
  • And Halls Harbour on the Fundy shore, a great spot for watching boats go from grounded to afloat in just an hour or so.


I timed my arrival at both sites to be there near lowest tide and shoot for about 3 hours as the tide came in, then stop shooting at about high tide.

Luckily, high tide on both days was about 3 p.m. making for convenient shoots on a summer afternoon. Being just after New Moon, the tides were near their highest.

Earth experiences two tides a day, at an interval of about 12 hours and 25 minutes, with the extra 25 minutes coming from the motion of the Moon around the Earth during that half-day interval. It takes another 25 minutes for us to line up with the Moon again.

But why two tides a day? If the Moon pulls at our water why isn’t there just one high tide, when the Moon is highest in our sky?

The Moon doesn’t pull on just the water. It pulls on everything.

And it isn’t the Moon’s gravity per se that raises the tides, it is the difference in the strength of that gravitational pull across an object.

The side of the Earth closest to the Moon feels the strongest pull, raising the tides on the side facing the Moon. But the Earth itself is also pulled toward the Moon, but to a lesser extent because the centre of our planet lies farther from the Moon.

In effect, the Moon pulls the Earth away from the water on the far side of the Earth, the side away from the Moon. This raises a bulge of water on the other side of our planet, the side that feels the least gravitational pull from the Moon because it is farthest from the Moon.

So as Earth rotates we pass through two tidal bulges, one facing the Moon and one facing away from the Moon.

Newton's Apple Tree

It wasn’t until Isaac Newton came along in the mid-17th century that we had an explanation for and an ability to predict the tides accurately. Even Galileo got it wrong. It was Newton’s mathematical explanation of how gravity fell off with increasing distance that led to an accurate theory of the tides. See Wikipedia for much more detail.

The tree above is a direct descendent of the famous “Newton’s Apple” tree that inspired his theory of universal gravitation. It is an apple tree on the picturesque grounds of Acadia University in Wolfville, Nova Scotia, and was grown from a cutting from the famous apple tree at Woolsthorpe Manor where Newton grew up and took refuge during the outbreak of plague in the cities.

Newton's Apple #1

It was during this retreat that, story has it – a story told by Newton himself – that an apple falling on his head inspired him to wonder if the same force that was causing the apple to fall was also keeping the Moon in perpetual orbit around the Earth.

Annapolis Tidal Generating Station

Today, we can turn the pull of the Moon into power, as here at Annapolis Royal where Nova Scotia Power operates the only tidal power station in North America, driven by water pouring into and out of the Annapolis River. The pull of the Moon here generates 20 megawatts of electricity.

New submerged turbines are now being tested in the Minas Basin, using a variety of technologies. A previous underwater turbine at the same site was ripped to pieces by the force of the water. Harnessing the tides is not so easy.

Tide watchers take note: The Full “supermoon” of September 27 (when there is also a total eclipse of the Moon) will be especially close. Favourable geometry will raise the highest tides in 18 years in the two days that follow the Full Moon.

The Moon truly has the power to move the waters and the Earth.

Many thanks to my host Dr. Roy Bishop for the tidal tour and elucidation. Click here to download an article of his about the tides. 

– Alan, August 21, 2015 / © 2015 Alan Dyer / www.amazingsky.com

A Plethora of Perseids


A composite depicting the Perseid meteor shower on the night of Wednesday, August 12, 2015 as shot from southern Alberta, Canada.  The image takes in a wide swath of the north and eastern sky, including the radiant of the shower in Perseus at left of centre, near the Double Cluster visible as a clump of stars. All the Perseids can be traced back to this point. Also in the image: the summer Milky Way and, at left, a dim aurora in green and magenta that was barely visible to the eye but was picked up by the camera. The Andromeda Galaxy is at centre. The Pleiades is just on the horizon. Apart from some haze from forest fire smoke, it was a near perfect night: warm, dry, just a little wind to keep the bugs at bay, and no Moon. A perfect night for a meteor watch.  This is a layered stack of 35 images recording three dozen meteors (most Perseids but also a couple of sporadics not aimed back to the radiant in Perseus, such as the bright one at far left).  The 35 images were selected from 200 shot from 11 pm to 2:30 am that night, with most frames not picking up any meteors. This composite is from the 35 taken over the 3.5 hours that did record a meteor. Each exposure is 1 minute at f/2.8 with the 15mm full-frame fish-eye, on the Canon 5D MkII at ISO 3200 (a couple of the early shots in the sequence were at ISO 1600 for 2 minutes).  The camera was tracking the sky on the Sky-Watcher Star Adventurer tracker, so all images of the stars are aligned and registered out of the camera, with the meteors in their proper position relative to the stars and radiant. I masked out a couple of satellite and aircraft trails that were distracting, and took away from the point of illustrating the radiant of the meteor shower.  The horizon, however, is from one image, taken early in the sequence. Some of the blue in the sky comes from one of the early shots taken in deep twilight but that contained a nice meteor. And I liked the blue it added.  All stacking and processing with Adobe Ca

It was a good year for Perseid meteors, as they shot across the sky in abundance on dark-of-the-Moon nights.

Last week, August 11 and 12 proved to be superb for weather in southern Alberta, with clear skies and warm temperatures perfect for a night of watching and shooting meteors.

On both nights I had identical camera rigs running, all from my rural backyard. These images are from the peak night, Wednesday, August 12.

The main image at top is with a 15mm ultra wide lens, on a camera that was tracking the sky as it turned. Like many meteor photos these days it is a layered stack of many images, in this case 35, to put as many meteors as possible onto one frame.

While the result does illustrate the effect of meteors streaking away from the radiant point, here in Perseus, it does lend a false impression of what the shower was like. It took me 3.5 hours of shooting to capture all of those meteors.

Note the aurora as well.

The Perseid meteor shower on peak night of Wednesday, August 12, 2015, showing meteors radiating from the “radiant point” in northern Perseus, then rising in the northeast sky. One bright sporadic, non-Perseid meteor is at left, and a small sporadic is near the horizon at right. The meteor at far left, top, may be a satellite streak.  The Andromeda Galaxy is at upper right. A dim aurora is at left in the northeast. The setting is a ripening canola field at home.  This is a stack of 16 images, one for the “base layer” ground and sky, containing a bright meteor, and 15 other images taken as part of the same sequence, each containing a meteor, layered with Photoshop using Lighten blend mode. I rotated each of the additional “meteor layers” around Polaris at upper left, so the sky aligned closely, putting the meteors in close to their correct position relative to the stars, to accurately illustrate the radiant effect. This was necessary as this sequence was shot with a fixed, non-tracking camera (the Canon 6D) using a 14mm Rokinon lens at f/2.8. Each exposure was 1 minute at ISO 3200. The 16 meteor frames came from a set of 212 frames taken over 3.5 hours. I layered in only the frames with meteors.  Frames were taken from 11 pm to 2:30 am MDT.

With this camera I used a wide 14mm lens, but with the camera on a fixed tripod. I again blended frames, 16 of them, to show the meteors radiating from Perseus.

Because the camera was not tracking the sky, later in Photoshop I rotated each frame relative to a lower “base-level” image, rotating them around Polaris at top as the sky does, in order to line up the stars and have the meteors appear in their correct position relative to the background stars and radiant point.

Note the errant bright “sporadic” meteor not part of the shower.

The Perseid meteors shooting through Cygnus and the Summer Triangle area of the summer Milky Way, on the night of Wednesday, August 12, 2015. Deneb is the star at top left, Vega at top right, and Altair at bottom. The Perseids shoot across the frame from top left to bottom right. Other streaks are sporadic meteors or short satellite trails. I masked out other long satellite trails that were distracting to the image’s focus on depicting Perseids. This is a stack of 24 images, each with a meteor or two, taken over a 3.5-hour period that night, with each exposure being 1 minute at f/2, with the 24mm Sigma lens and Nikon D750 at ISO 1600. The 24 image with meteors were selected from a total of 214 shot for this sequence, with most frames not recording any meteor, and perhaps only satellites or aircraft.

Camera number 3 was aimed straight up for 3.5 hours, toward Cygnus and the Summer Triangle, in hopes of nabbing that brilliant fireball streaking down the Milky Way. I got a nice “rain of meteors” effect but the bright bolide meteor eluded me.

This was certainly the best year for the Perseids in some time, with it coinciding with New Moon.

Later this year, the Geminids will also put on a good show at nearly New Moon, on the nights of December 13 and 14. So if you liked, or missed, the Perseids, take note of the dates in December.

However, for many of us, a Geminid watch is a very, cold and snowy affair!

— Alan, August 18, 2015 / © 2015 Alan Dyer / www.amazingsky.com 

How to See & Shoot the Perseids


A trio of Perseid meteors shoot at left in the pre-dawn sky over Lake Minnewanka in Banff National Park. The overexposed waning crescent Moon shines between Venus (below) and Jupiter (above), with Jupiter near the Hyades and below the Pleiades in Taurus. Taken the morning of Sunday, August 12, 2012 with the Canon 5D MkII and 24mm Canon L-series lens. This is a composite of three exposures, one for each meteor, each for 40 seconds at ISO 2000 and f/5. Landscape is from one image, two other meteors from two other frames layered in and registered in the correct position in the base layer.

It’s Perseid meteor shower time. Here are tips for seeing and shooting the meteors.

What are the Perseids?

They are an annual meteor shower, perhaps the most widely observed of the year, that peak every year about August 12. They are caused by Earth passing through a dust stream left by Comet Swift-Tuttle, last seen near Earth in 1992.

Each “shooting star” is really a bit of comet dust burning up in our atmosphere as it ploughs into us at 200,000 kilometres an hour. They don’t stand a chance of surviving – and none do.

All Perseid particles burn up. None reach Earth.

Perseid meteor caught night of August 12-13 2009 from Cypress Hills Prov Park in Saskatchewan at the annual Saskatchewan Summer Star Party. One frame of 250 shot as part of a time-lapse movie. Taken with Canon 5D MkII and 24mm lens at f/2.5 for 30s at ISO1600.
Perseid meteor caught night of August 12-13 2009 from Cypress Hills Prov Park in Saskatchewan at the annual Saskatchewan Summer Star Party. One frame of 250 shot as part of a time-lapse movie. Taken with Canon 5D MkII and 24mm lens at f/2.5 for 30s at ISO1600.

When are the Perseids?

The peak night of the Perseids this year is the night of Wednesday, August 12 into the early morning hours of August 13, with the peak hour occurring about midnight Mountain Daylight Time or 2 a.m. on the 13th for Eastern Daylight Time.

For North America, this is ideal timing for a good show this year. However, a good number of meteors will be visible the night before and night after peak night.

Even better, the Moon is near New and so won’t interfere with the viewing by lighting up the sky.

In all, except for the mid-week timing, conditions this year in 2015 couldn’t be better!

Perseid meteor caught night of August 12-13 2009 from Cypress Hills Prov Park in Saskatchewan at the annual Saskatchewan Summer Star Party. One frame of 260 shot as part of a time-lapse movie. Taken with Canon 20Da and 15mm lens at f/2.8 for 45s at ISO1600.
Perseid meteor caught night of August 12-13 2009 from Cypress Hills Prov Park in Saskatchewan at the annual Saskatchewan Summer Star Party. One frame of 260 shot as part of a time-lapse movie. Taken with Canon 20Da and 15mm lens at f/2.8 for 45s at ISO1600.

What do they look like?

Any meteor looks like a brief streak of light shooting across the sky. The brightest will outshine the brightest stars and are sure to evoke a “wow!” reaction.

However, the spectacular Perseids are the least frequent. From a dark site, expect to see about 40 to 80 meteors in an hour of patient and observant watching, but of those, only a handful – perhaps only 1 or 2 – will be “wow!” meteors.

A pair of Perseid meteors shoot at left in the late night sky at the Upper Bankhead parking lot in Banff National Park. The  waning crescent Moon is just rising above the trees. A faint Perseid is at right, while a satellite trail goes from left to right as well.  Taken the night of Saturday, August 11 into the wee hours of Sunday, August 12, 2012 with the Canon 7D and 10-22mm Canon lens. This is a stack of two exposures, one for each meteor, each for 60 seconds at ISO 1250 and f/4. The stars are trailed slightly due to the two-minute exposure time in total.
A pair of Perseid meteors shoot at left in the late night sky at the Upper Bankhead parking lot in Banff National Park. The waning crescent Moon is just rising above the trees. 
Taken the night of Saturday, August 11 into the wee hours of Sunday, August 12, 2012 with the Canon 7D and 10-22mm Canon lens. This is a stack of two exposures, one for each meteor, each for 60 seconds at ISO 1250 and f/4. 

Where do I look?

All the meteors will appear to radiate from a point in the constellation of Perseus in the northeastern sky in the early hours of the night, climbing to high overhead by dawn.

So you can face that direction if you wish, but Perseids can appear anywhere in the sky, with the longest meteor trails often opposite the radiant point, over in the southwest.

Shows unusual Perseid meteor varying in brightness? Or is this a satellite that mimics Perseid for position (it comes right out of the radiant point).  Taken at SSSP, August 14, 2010, using Canon 5D MkII and 15mm lens.
Shows unusual Perseid meteor varying in brightness? Or is this a satellite that mimics Perseid for position (it comes right out of the radiant point). Taken at Saskatchewan Star Party, August 14, 2010, using Canon 5D MkII and 15mm lens.

How do I look?

Simple – just lie back on a comfy lawn chair or patch of grass and look up!

But … you need to be at a dark location away from city lights to see the most meteors. You’ll see very little in a city or light-polluted suburbs.

Head to a site as far from city lights as you can, to wherever you’ll be safe and comfortable.

How do I take pictures?

To stand any chance of capturing these brief meteors you’ll need a good low-noise camera (a DSLR or Compact System Camera) with a fast (f/2.8 or faster) wide-angle lens (10mm to 24mm).

Sorry, keep your point-and-shoot camera and phone camera tucked away in your pocket – they won’t work.

Set up you camera on a tripod, open the lens to f/2.8 (wide open perhaps) and the ISO to 800 to 3200) and take a test exposure of 20 to 40 seconds. You want a well-exposed image but not over-exposed so the sky is washed out.

Set your exposure time accordingly – most cameras allow a maximum exposure of 30 seconds. Exposures longer than 30 seconds require a separate intervalometer to set the exposure, with the camera set on Bulb (B).

Take lots of pictures!

To up your chances of catching a meteor, you need to set the camera to shoot lots of frames in rapid succession.

Use an intervalometer to take shots one after the other with as little time between as possible – because that’s when a meteor will appear!

Barring an intervalometer, if you have standard switch remote control, set the camera on High Speed Continuous, and the shutter speed to 30 seconds, then lock the remote’s switch to ON to keep the camera firing. As soon as one exposure ends it’ll fire another.

Twin Perseids in this photo? Or are these satellites?  Taken at SSSP, August 14, 2010, using Canon 5D MkII and 15mm lens.
Twin Perseids in this photo? Or are these satellites? Taken at SSSP, August 14, 2010, using Canon 5D MkII and 15mm lens.

What else do I need to know?

• Focus the lens carefully so the stars are sharp – the Live Focus mode helps for this. Focus on a bright star or distant light.

• Aim the camera to take in a wide swath of the sky but include a well-composed foreground for the most attractive shot.

• Aim northeast to capture meteors streaking away from the radiant. But you can aim the camera to any direction that lends itself to a good composition and still capture a meteor.

• To increase your chances, shoot with two or more cameras aimed to different areas of the sky. Meteors always appear where your camera isn’t aimed!

• Be patient! Despite shooting hundreds of frames only a handful will record a meteor, as only the brightest will show up.

Can I track the sky?

If you have a motorized equatorial mount or a dedicated sky tracking device (the iOptron Sky Tracker and Sky-Watcher Star Adventurer, each about $400, are popular), you can follow the stars while taking lots of shots. This avoids the stars trailing and allows you to use longer exposures.

The video above shows a Star Adventurer tracking the sky as it turns about its polar axis which is aimed up to a point near Polaris. Click the Enlarge and HD buttons to view the video properly.

Polar align the tracker, but then perhaps aim the camera to frame the summer Milky Way overhead. Take lots of 1- to 3-minute exposures, again at f/2.8 and ISO 800 to 1600. Some exposures will pick up meteors – with luck!

Tracking then stacking

Later, in processing, because the sky has remained fixed on the frame, it’s then possible to stack the images (using a “Lighten” blend mode on each image layer) so that the final composite frame contains more meteors, for an image with lots of meteors captured over an hour or more of shooting.

While it is possible to stack shots taken on a static tripod to produce such a meteor composite, doing so requires a lot of manual cutting, pasting and aligning of meteor images by hand. The result is a bit of a fake, though I’ve done it myself – the image at top is an example, though with only a trio of meteors.

Good luck and happy meteor watching!

– Alan, August 6, 2015 / © 2015 Alan Dyer / www.amazingsky.com 

Moonlight on the Prairie


The rising almost-Full Moon, a “Blue Moon” of July 30, 2015, rising behind a rustic old farmhouse near Bow Island, Alberta. The Moon sits in the pibk Belt of Venus with the blue shadow of the Earth below. This is a single frame from a 600-frame time-lapse sequence, taken with the Canon 6D and 16-35mm lens.

I present a short time-lapse vignette of scenes shot under moonlight on the Alberta prairie.

The movie linked below features sequences shot July 29 and 30, 2015 on beautifully clear moonlit nights at locations south of Bow Island, Alberta, on the wide open prairie. The three-minute video features two photogenic pioneer sites.

Circumpolar star trails over the historic but sadly neglected St. Anthony’s Church between Bow Island and Etzikom, Alberta. The Big Dipper is at left, Polaris at top. The Roman Catholic church was built in 1911 by English, Russian German immigrants. It served a dwindling congregation until 1991 when it closed. At that time workers found a time capsule from 1915 with names of the priest and parisioners of the day. In summer of 2014 the Church suffered its latest indignity when the iron cross on its steeple tower was stolen. It was there when I stopped at this Church on a site scouting trip in May 2014. I planned to return on a moonlit night and did on July 29, 2015. A nearby house had been torn down and the cross was now gone.  This is a stack of 300 6-second exposures with the Canon 6D at ISO 1600 and 16-35mm lens at f/2.8. Bright light from a 13-day Moon lights the scene, making for very short exposures. The ground comes from one exposure to keep shadows sharp. The final stars also come from another single exppsure taken two minutes after the last trail image. I used the Advanced Stacker Actions to stack the trails.

The church is the now derelict St. Anthony’s Church, a former Roman Catholic church built in 1911 by English and Russian-German immigrants. It served a dwindling congregation until as late as 1991 when it closed. At that time workers found a time capsule from 1915 with names of the priest and parisioners of the day.

The wood church seems to have been largely neglected since.

In the summer of 2014 the Church suffered its latest indignity when the iron cross on its steeple tower was stolen. I also shot in the pioneer cemetery of the Church.

Circumpolar star trails circling above an old rustic and abandoned house near Bow Island, Alberta, with illumination from the nearly Full Moon. Cassiopeia is near centre. Polaris is at top left.  This is a stack of 140 frames from a time-lapse sequence with additional frames added for the first and last stars, and the ground coming from a mean combine stack of 8 frames to reduce noise. Each frame is 10 seconds at f/4 with the 16-35mm lens and ISO 1600 with the Canon 6D. Stacked with Advanced Stacker Actions, using the Ultrastreaks effect, from within Photoshop.

The other site is a nearby farmhouse with photogenic textures and accompanied by rustic out buildings that are barely managing to stand.

Illumination was from a waxing gibbous Moon, just 1 to 2 days before the infamous “Blue Moon” of July 31. Its bright light turned the sky blue, and lit the landscape with the same quality as sunlight, because it is sunlight!


Enlarge the video to full screen for the full HD version.

For the technically inclined:

I shot the scenes with three cameras – a Canon 60Da, Canon 6D, and Nikon D750.

The Nikon, with a 24mm lens, was on the Dynamic Perception Stage Zero Dolly and Stage R panning unit, while the 60Da, with a 14mm lens, was on the compact Radian panning unit. The third camera, the 6D, with a 16-35mm lens, was on a fixed tripod for the star trail sequences and stills.

The music is by Adi Goldstein (AGSoundtrax.com), whose music I often use in my sequences. It just seems to work so well, and is wonderfully melodic and powerful. Thank you, Adi!

To process the several thousand frames that went into the final movie, I used Adobe Bridge and Adobe Camera Raw, supplemented by the latest Version 4.2 of LRTimelapse (lrtimelapse.com). Its new “Visual Deflicker” workflow does a beautiful job smoothing out frame-to-frame flickering in sequences shot in twilight under darkening lighting conditions. Thank you Gunther!

For the star trail sequences and the still images above I used the Advanced Stacker Actions from StarCircleAcademy.com. Unlike most other stacking programs, the Stacker Actions work from within Adobe Bridge and Photoshop directly, using the processed Raw images, with no need to create intermediate sets of JPGs. Thank you Steven!

— Alan, August 3, 2015 / © 2015 Alan Dyer / www.amazingsky.com 

Sunset over Horsethief Canyon


Sunset on August 1, 2015 at the Horsethief Canyon Viewpoint overlooking the Red Deer River, north of Drumheller, Alberta, on the Dinosaur Trail scenic drive. The name comes from the pioneer days when horses would get lost in the Badlands here and then re-emerge found, but with a new brand on them. The region is home to rich deposits of late Cretaceous dinosaur fossils. Just south of here is the world class Royal Tyrrell Museum, a centre of research into dinosaurs and prehistoric life.  This is a single-exposure frame (not HDR) from a 300-frame time-lapse sequence, with the Canon 6D and 16-35mm lens.

The Sun sets over the Red Deer River Badlands at Horsethief Canyon

This was sunset last night, Saturday, August 1, at the Horsethief Canyon Viewpoint overlooking the Red Deer River, north of Drumheller, Alberta.

The viewpoint is one stop on the Dinosaur Trail scenic drive that winds up and down the river valley, with a crossing just north of here by one of the few remaining river ferries in Alberta, the historic Bleriot Ferry.

The Canyon’s name comes from the pioneer days when horses would get lost in the Badlands here, then re-emerge found, but with a new brand on them.

The region is home to rich deposits of late-Cretaceous dinosaur fossils. Just south of here is the world-class Royal Tyrrell Museum, a centre of research into dinosaurs and prehistoric life.

This is a single-exposure frame (not HDR) from a 300-frame time-lapse sequence, with the Canon 6D and 16-35mm lens.

– Alan. August 2, 2015 / © 2015 Alan Dyer / www.amazingsky.com

The “Blue Moon” over Calgary


The Full Moon of July 31, 2015, an infamous “blue Moon”, the second Full Moon of July, rising over the skyline of Calgary, Alberta. This is one frame of a 480-frame time-lapse sequence taken with the Canon 60Da and 28-105mm lens. The location was Toronto Crescent.

The much-publicized “Blue Moon” of July rises over the skyline of Calgary.

Last night, July 31, many people looked east to see a wonderful moonrise. Did it look different than any other moonrise? No. But did it look great? You bet.

I set up my cameras at a site in northwest Calgary, picked for its sightline looking east-southeast over the downtown core of Calgary and directly toward the moonrise point.

I used the software The Photographer’s Ephemeris to plan the location and angles. It is wonderful for making sure you are in the right place at the right time for catching a photogenic moonset or moonset.

Here’s the screen shot from TPE that showed me where to be Friday evening. The blue line aims to the moonrise point.

IMG_2473

Of course, despite the planning the Moon did not look blue! Blue Moons, as they have come to be defined, never do. The term now means the second Full Moon in a calendar month. We had a Full Moon on Canada Day, July 1, and then enjoyed a second July Full Moon one lunar cycle later on July 31.

I shot the scene with two cameras, each shooting hundreds of frames for time-lapses, from which I extracted still images.

A short 1-minute music video of the result is here at Vimeo. Enlarge the screen and be sure HD is selected.


As a technical note, for the processing I used the latest version 4.2 of LRTimelapse and its new “Visual Deflicker” workflow which very nicely smooths out all the frame-to-frame flickering that can plague daytime and twilight shots taken under Auto Exposure.

While the shutter speed does constantly decrease, it does so in 1/3rd-f/stop steps, yielding stair-step jumps in brightness. LRT smooths all that out, with v4.2 doing a much better job than earlier versions.

Thanks for watching!

— Alan, August 1, 2015 / © 2015 Alan Dyer / www.amazingsky.com