How to Shoot “Deep-Sky with Your DSLR”


KSPage-Feb7We’ve embarked upon a new project to produce a comprehensive tutorial on deep-sky imaging with DSLR cameras.

This past week we launched a new KickStarter campaign to fund the production of a new multi-hour video course on how to capture deep-sky objects using entry-level telescope gear and DSLR cameras.

The emphasis in the course will be on techniques for taking and processing publication-quality images as simply and easily as possible.

A Frosty Telescope Shooting Andromeda

The final video course will consist of several programs, including a video of one of our annual “Deep-Sky with Your DSLR” workshops presented locally here in Alberta. We’ve often had requests for a video version of those workshops, for those who cannot attend in person.

This is it! Here’s a short preview of some of the content.

 

We include the Workshop video, but we supplement it with much more: with video segments shot in the field by day and by night, showing how to setup and use gear, and shot in the studio showing how to process images.

Deep-Sky Photo Session in the Backyard

While much of the content has been shot and edited, there’s more to do yet. Thus our KickStarter campaign to complete the funding and production. Backers of the project through KickStarter will get the final videos at a substantial discount off the final retail price.

All the details are on the project’s KickStarter page. Click through for the listing of course content, and options for funding levels. An FAQ page answers many of the common questions.

A week into the campaign and we’re just over 50% funded, but we have a way to go yet!

M31 with Orion 80mm Apo and Celestron AVX Mount (Multiple Exposu

We hope you’ll consider backing our project, which we think will be unique on the market.

Clear skies!

— Alan, February 7, 2019 / © 2019 / AmazingSky.com 

 

 

 

Chasing the Eclipse of the Cold Moon


Eclipsed Moon and Umbral Shadow

It took a chase but it was worth it to catch the January 20, 2019 total eclipse of the Moon in the winter sky.

While the internet and popular press fawned over the bogus moniker of “Super Blood Wolf” Moon, to me this was the “Cold Moon” eclipse. And I suspect that was true for many other observers and eclipse chasers last Sunday.

Total solar eclipses almost always involve a chase, usually to far flung places around the world to stand in the narrow shadow path. But total lunar eclipses (TLEs) come to you, with more than half the planet able to view the Moon pass through the Earth’s shadow and turn red for several minutes to over an hour.

The glitch is clouds. For several of the last TLEs I have had to chase, to find clear skies in my local area, creating pre-eclipse stress … and post-eclipse relief!

astrospheric map
A screen shot from Astrospheric

That was the case for the January 20, 2019 total lunar, as the weather predictions above, based on Environment Canada data, were showing east-central Alberta along the Saskatchewan border as the only clear hole within range and accessible.

The above is a screen shot from the wonderful app Astrospheric, a recommended and great aid to astronomers. In 2014, 2015, and 2018 the Environment Canada predictions led me to clear skies, allowing me to see an eclipse that others in my area missed.

So trusting the predictions, the day before the eclipse I drove the 5 hours and 500 km north and east to Lloydminster, a town where the provincial border runs right down the main street, Highway 17.

Theodolite_2019.01.20_11.35.06
A screen shot from Theodolite

The morning of the evening eclipse, I drove up and down that highway looking for a suitable site to setup. Scenery was not in abundance! It’s farm land and oil wells. I settled for a site shown above, an access road to a set of wells and tanks where I would likely not be disturbed, that had no lights, and had a clear view of the sky.

The image above is from the iOS app Theodolite, another fine app for planning and scouting sites, as it overlays where the camera was looking.

Scenery was not a priority as I was mostly after a telephoto view of the eclipsed Moon near the Beehive star cluster. Wide views would be a bonus if I could get them, for use in further ebook projects, as is the plan for the image below.

Looking at the Lunar Eclipse with Binoculars
This is a single untracked exposure of 25 seconds at f/2.8 and ISO 1600 with the Nikon D750 and Sigma 20mm Art lens, but with a shorter exposure of 1 second blended in for the Moon itself so it retains its color and appearance to the naked eye. Your eye can see the eclipsed Moon and Milky Way well but the camera cannot in a single exposure. The scene, taken just after the start of totality, just fit into the field of the 20mm lens. A little later in the night it did not. 

The site, which was east of the border in Saskatchewan, served me well, and the skies behaved just as I had hoped, with not a cloud nor haze to interfere with the view. It was a long and cold 5-hour night on the Prairies, with the temperature around -15° C.

It could have been worse, with -25° not uncommon at this time of year. And fortunately, the wind was negligible, with none of the problems with frost that can happen on still nights.

Nevertheless, I kept my photo ambitions in check, as in the cold much can go wrong and running two cameras was enough!

Eclipsed Moon Beside the Beehive
The Moon in mid-total eclipse, on January 20, 2019, with it shining beside the Beehive star cluster, Messier 44, in Cancer. This view tries to emulate the visual scene through binoculars, though the camera picks up more stars and makes the Moon more vivid than it appears to the eye. However, creating a view that looks even close to what the eye can see in this case takes a blend of exposures: a 1-minute exposure at ISO 800 and f/2.8 for the stars, which inevitably overexposes the Moon. So I’ve blended in three shorter exposures for the Moon, taken immediately after the long “star” exposure. These were 8, 4 and 2 seconds at ISO 400 and f/4, and all with the Canon 200mm telephoto on a Fornax Lightrack II tracking mount to follow the stars. 

Above was the main image I was after, capturing the red Moon shining next to the Beehive star cluster, a sight we will not see again for another 18-year-long eclipse “saros,” in January 2037.

But I shot images every 10 minutes, to capture the progression of the Moon through the shadow of the Earth, for assembly into a composite. I’d pick the suitable images later and stack them to produce a view of the Moon and umbral shadow outline set amid the stars.

Eclipsed Moon and Umbral Shadow
The Moon in total eclipse, on January 20, 2019, in a multiple exposure composite showing the Moon moving from right to left (west to east) through the Earth’s umbral shadow. The middle image is from just after mid-totality at about 10:21 pm MST, while the partial eclipse shadow ingress image set is from 9:15 pm and the partial eclipse shadow egress image set is from 11:15 pm. I added in two images at either end taken at the very start and end of the umbral eclipse to add a more complete sequence of the lunar motion. The central image of totality includes a 1-minute exposure at ISO 800 and f/2.8 for the stars, which inevitably overexposes the Moon. So I’ve blended in three shorter exposures for the Moon, taken immediately after the long “star” exposure. These were 8, 4 and 2 seconds at ISO 400 and f/4, and all with the Canon 200mm telephoto. The two partial eclipse phases are stacks of 7 exposures each, from very short for the bright portion of the lunar disk, to long for the shadowed portion. They are blended with luminosity masks created with ADP Pro v3 panel for Photoshop, but modified with feathering to blend the images smoothly. 

Above is the final result, showing the outline of the circular umbral shadow of the Earth defined by the shadow edge on the partially eclipsed Moons. The umbra is about three times the size of the Moon. And at this eclipse the Moon moved across the northern half of the shadow.

So mission accomplished!

Success Selfie with Lunar Eclipse (Jan 20, 2019)
This is an untracked single exposure of 15 seconds at ISO 3200 and f/2.8 with the Sigma 20mm Art lens and Nikon D750. However, I blended in a shorter 1-second exposure for the red eclipsed Moon itself to prevent its disk from overexposing as it would in any exposure long enough to record the Milky Way. 

I usually try to take a “trophy” shot of the successful eclipse chaser having bagged his game. This is it, from mid-eclipse during totality, with the red Moon shining in the winter sky beside the Beehive.

With this eclipse I can now say I have seen every total lunar eclipse visible from my area of the world since May 2003. I’m not counting those TLEs that were visible from only the eastern hemisphere — I’m not so avid as to chase those. And there were a couple of TLEs in that time that were visible from North America, but not from Alberta. So I’m not counting those.

And a couple of TLEs that were visible from here I did not see from here in Alberta — I saw April 15, 2014 from Australia and April 4, 2015 from Utah.

With that tally I’ve seen all the locally visible TLEs over a full saros cycle, 18 years. The last local TLE I missed was January 20, 2000, exactly 19 years — a Metonic cycle — ago. It must have been cloudy!

may 21, 2021 eclipse

The next total eclipse of the Moon is May 26, 2021, visible from Alberta as the Moon sets at dawn. I’d like to be in Australia for that one (depicted above in a screen shot from StarryNight™), to see the eclipsed Moon beside the galactic centre as both rise in the east, a sight to remember. Being late austral autumn, that will be a “cool Moon.”

Happy eclipse chasing!

— Alan, January 22, 2019 / © 2019 Alan Dyer / AmazingSky.com 

 

Photographing the Total Eclipse of the Moon


Lunar Eclipse CompositeOn the evening of January 20 for North America, the Full Moon passes through the umbral shadow of the Earth, creating a total eclipse of the Moon. 

No, this isn’t a “blood,” “super,” nor “wolf” Moon. All those terms are internet fabrications designed to bait clicks.

It is a   total   lunar  eclipse  — an event that doesn’t need sensational adjectives to hype, because they are always wonderful sights! And yes, the Full Moon does turn red.

As such, on January 20 the evening and midnight event provides many opportunities for great photos of a reddened Moon in the winter sky. 

Here’s my survey of tips and techniques for capturing the eclipsed Moon. 


First … What is a Lunar Eclipse?

As the animation below shows (courtesy NASA/Goddard Space Flight Center), an eclipse of the Moon occurs when the Full Moon (and they can happen only when the Moon is exactly full) travels through the shadow of the Earth. 

The Moon does so at least two times each year, though often not as a total eclipse, one where the entire disk of the Moon enters the central umbral shadow. Many lunar eclipses are of the imperceptible penumbral variety, or are only partial eclipses.

Total eclipses of the Moon can often be years apart. The last two were just last year, on January 31 and July 27, 2018. However, the next is not until May 26, 2021.

For a short explanation of the geometry of lunar eclipses see the NASA/Goddard video at https://svs.gsfc.nasa.gov/11516 

At any lunar eclipse we see an obvious darkening of the lunar disk only when the Moon begins to enter the umbra. That’s when the partial eclipse begins, and we see a dark bite appear on the left edge of the Moon. 

While it looks as if Earth’s shadow sweeps across the Moon, it is really the Moon moving into, then out of, our planet’s umbra that causes the eclipse. We are seeing the Moon’s revolution in its orbit around Earth. 

At this eclipse the partial phases last 67 minutes before and after totality. 

Telescope CU-Stages
This shows the length of the eclipse phases relative to the start of the partial eclipse as the Moon begins to enter the umbra at right. The Moon’s orbital motion takes it through the umbra from right to left (west to east) relative to the background stars. The visible eclipse ends 196 minutes (3 hours and 16 minutes) after it began. Click or tap on the charts to download a high-res version.

Once the Moon is completely immersed in the umbra, totality begins and lasts 62 minutes at this eclipse, a generous length. 

The Moon will appear darkest and reddest at mid-eclipse. During totality the lunar disk is illuminated only by red sunlight filtering through Earth’s atmosphere. It is the light of all the sunsets and sunrises going on around our planet. 

And yes, it is perfectly safe to look at the eclipsed Moon with whatever optics you wish. Binoculars often provide the best view. Do have a pair handy!

Total Lunar Eclipse (December 20/21, 2010)
Total eclipse of the Moon, December 20/21, 2010, taken from home with 130mm AP apo refractor at f/6 and Canon 7D at ISO 400 for 4 seconds, single exposure, shortly after totality began.

At this eclipse because the Moon passes across the north half of the umbra, the top edge of the Moon will always remain bright, as it did above in 2010, looking like a polar cap on the reddened Moon.

Near the bright edge of the umbra look for subtle green and blue tints the eye can see and that the camera can capture.


Where is the Eclipse?

As the chart below shows, all of the Americas can see the entire eclipse, with the Moon high in the evening or late-night sky. For the record, the Moon will be overhead at mid-eclipse at local midnight from Cuba!

LE2019Jan21T
All of the Americas can see this eclipse. The eclipse gets underway as the Moon sets at dawn over Europe. Diagram courtesy EclipseWise.com

For more details on times see www.EclipseWise.com and the event page at http://www.eclipsewise.com/lunar/LEprime/2001-2100/LE2019Jan21Tprime.html 

I live in Alberta, Canada, at a latitude of 50 degrees North. And so, the sky charts I provide here are for my area, where the Moon enters the umbral shadow at 8:35 p.m. MST with the Moon high in the east. By the end of totality at 10:44 p.m. MST the Moon shines high in the southeast. This sample chart is for mid-eclipse at my site.

Framing TL-Mid-Eclipse
The sky at mid-eclipse from my Alberta site. Created with the planetarium software Starry Night, from Simulation Curriculum.

I offer them as examples of the kinds of planning you can do to ensure great photos. I can’t provide charts good for all the continent because exactly where the Moon will be during totality, and the path it will take across your sky will vary with your location. 

In general, the farther east and south you live in North America the higher the Moon will appear. But from all sites in North America the Moon will always appear high and generally to the south. 

To plan your local shoot, I suggest using planetarium software such as the free Stellarium or Starry Night (the software I used to prepare the sky charts in this post), and photo planning apps such as The Photographer’s Ephemeris or PhotoPills. 

The latter two apps present the sightlines toward the Moon overlaid on a map of your location, to help you plan where to be to shoot the eclipsed Moon above a suitable foreground, if that’s your photographic goal. 


When is the Eclipse?

While where the Moon is in your sky depends on your site, the various eclipse events happen at the same time for everyone, with differences in hour due only to the time zone you are in. 

While all of North America can see the entirety of the partial and total phases of this eclipse (lasting 3 hours and 16 minutes from start to finish), the farther east you live the later the eclipse occurs, making for a long, late night for viewers on the east coast. 

Those in western North America can enjoy all of totality and be in bed at or before midnight.

Here are the times for the start and end of the partial and total phases. Because the penumbral phases produce an almost imperceptible darkening, I don’t list the times below for the start and end of the penumbral eclipse. 

Eclipse Times Table

PM times are on the evening of January 20.

AM times are after midnight on January 21.

Note that while some sources list this eclipse as occurring on January 21, that is true for Universal Time (Greenwich Time) and for sites in Europe where the eclipse occurs at dawn near moonset. 

For North America, if you go out on the evening of January 21 expecting to see the eclipse you’ll be a day late and disappointed! 


Picking a Photo Technique

Lunar eclipses lend themselves to a wide range of techniques, from a simple camera on a tripod, to a telescope on a tracking mount following the sky. 

If this is your first lunar eclipse I suggest keeping it simple! Select just one technique, to focus your attention on only one camera on a cold and late winter night. 

Lunar Eclipse Closeup with Stars
The total eclipse of the Moon of September 27, 2015, through a telescope, at mid-totality with the Moon at its darkest and deepest into the umbral shadow, in a long exposure to bring out the stars surrounding the dark red moon. This is a single exposure taken through a 92mm refractor at f/5.5 for 500mm focal length using the Canon 60Da at ISO 400 for 8 seconds. The telescope was on a SkyWatcher HEQ5 equatorial mount tracking at the lunar rate.

Then during the hour of totality take the time to enjoy the view through binoculars and with the unaided eye. No photo quite captures the glowing quality of an eclipsed Moon. But here’s how to try it.


Option 1: Simple — Camera-on-Tripod

The easiest method is to take single shots using a very wide-angle lens (assuming you also want to include the landscape below) with the camera on a fixed tripod. No fancy sky trackers are needed here. 

During totality, with the Moon now dimmed and in a dark sky, use a good DSLR or mirrorless camera in Manual (M) mode (not an automatic exposure mode) for settings of 2 to 20 seconds at f/2.8 to f/4 at ISO 400 to 1600. 

That’s a wide range, to be sure, but it will vary a lot depending on how bright the sky is at your site. Shoot at lots of different settings, as blending multiple exposures later in processing is often the best way to reproduce the scene as your eyes saw it. 

Shoot at a high ISO if you must to prevent blurring from sky motion. However, lower ISOs, if you can use them by choosing a slower shutter speed or wider lens aperture, will yield less digital noise.

Focus carefully on a bright star, as per the advice below for telephoto lenses. Don’t just set the lens focus to infinity, as that might not produce the sharpest stars.

Total Lunar Eclipse (December 20/21, 2010)
Total eclipse of the Moon, December 20/21, 2010, with 15mm lens at f/3.2 and Canon 5D MkII at ISO 1600 for a 1-minute tracked exposure. Without a tracker, use shorter exposures (less than 20 seconds) and higher ISOs or wider apertures to avoid trailing,

One scene to go for at this eclipse is similar to the above photo, with the reddened Moon above a winter landscape and shining east of Orion and the winter Milky Way. But that will require shooting from a dark site away from urban lights. But when the Moon is totally eclipsed, the sky will be dark enough for the Milky Way to appear. 

Framing Eclipse Sky
Click or tap on any of the charts to download a high-resolution copy.

The high altitude of the Moon at mid-eclipse from North America (with it 40 to 70 degrees above the horizon) will also demand a lens as wide as 10mm to 24mm, depending whether you use portrait or landscape orientation, and if your camera uses a cropped frame or full frame sensor. The latter have the advantage in this category of wide-angle nightscape. 

Framing Winter Milky Way & Moon

Alternatively, using a longer 14mm to 35mm lens allows you to frame the Moon beside Orion and the winter Milky Way, as above, but without the landscape. Again, this will require a dark rural site.

If you take this type of image with a camera on a fixed tripod, use high ISOs to keep exposures below 10 to 20 seconds to avoid star trailing. You have an hour of totality to shoot lots of exposures to make sure some will work best.

Total Lunar Eclipse, Dec 20, 2010 24mm Wide-Angle
Total eclipse of the Moon, December 20/21, 2010, with Canon 5D MKII and 24mm lens at f2.8 for stack of four 2-minute exposures at ISO 800. Taken during totality using a motorized sky tracker. The eclipsed Moon is the red object above Orion, and the stars appear bloated due to high haze and fog rolling in.

If you have a sky tracker to follow the stars, as I did above, exposures can be much longer — perhaps a minute to pick up the Milky Way really well — and ISOs can be lower to avoid noise. 


Option 1 Variation — Urban Eclipses

Unfortunately, point-and-shoot cameras and so-called “bridge” cameras, ones with non-interchangeable lenses, likely won’t have lenses wide enough to capture the whole scene, landscape and all. Plus their sensors will be noisy when used at high ISOs. Those cameras might be best used to capture moderate telephoto closeups at bright urban sites. 

With any camera, at urban sites look for scenic opportunities to capture the eclipsed Moon above a skyline or behind a notable landmark. By looking up from below you might be able to frame the Moon beside a church spire, iconic building, or a famous statue using a normal or short telephoto lens, making this a good project for those without ultra-wide lenses.

Total Lunar Eclipse, Feb. 20, 2008
Lunar eclipse, Feb 20, 2008 with a 135mm telephoto and Canon 20Da camera showing the Moon’s size with such a lens and cropped-frame camera. This is a blend of 8-second and 3-second exposures to bring out stars and retain the Moon. Both at ISO200 and f/2.8. Saturn is at lower left and Regulus at upper right.

Whatever your lens or subject, at urban sites expose as best you can for the foreground, trying to avoid any bright and bare lights in the frame that will flood the image with lens flares in long exposures. 

Capturing such a scene during the deep partial phases might produce a brighter Moon that stands out better in an urban sky than will a photo taken at mid-totality when the Moon is darkest. 


TIP: Practice, Practice, Practice!

With any camera, especially beginner point-and-shoots, ensure success on eclipse night by practicing shooting the Moon before the eclipse, during the two weeks of the waxing Moon leading up to Full Moon night and the eclipse.

The crescent Moon with Earthshine on the dark side of the Moon is a good stand-in for the eclipsed Moon. Set aside the nights of January 8 to 11 to shoot the crescent Moon. Check for exposure and focus. Can you record the faint Earthshine? It’s similar in brightness to the shadowed side of the eclipsed Full Moon.

The next week, on the nights of January 18 and 19, the waxing gibbous Moon will be closer to its position for eclipse night and almost as bright as the uneclipsed Full Moon, allowing some rehearsals for shooting it near a landmark.


Option 2: Advanced — Multiple Exposures

An advanced method is to compose the scene so the lens frames the entire path of the Moon for the 3 hours and 16 minutes from the start to the end of the partial eclipse. 

Framing TL-Start of Eclipse
This set of 3 charts shows the position of the Moon at the start, middle, and end of the eclipse, for planning lens choice and framing of the complete eclipse path. The location is Alberta, Canada.

Framing TL-Mid-Eclipse

Framing TL-End of Eclipse

As shown above, including the landscape will require at least a 20mm lens on a full frame camera, or 12mm lens on a cropped frame camera. However, these charts are for my site in western Canada. From sites to the east and south where the Moon is higher an even wider lens might be needed, making this a tough sequence to take.

With wide lenses, the Moon will appear quite small. The high altitude of the Moon and midnight timing won’t lend itself to this type of multiple image composite as well as it does for eclipses that happen near moonrise or moonset, as per the example below. 

Lunar Eclipse From Beginning to End, To True Scale
This is a multiple-exposure composite of the total lunar eclipse of Sunday, September 27, 2015, as shot from Writing-on-Stone Provincial Park, Alberta, Canada. For this still image composite of the eclipse from beginning to end, I selected just 40 frames taken at 5-minute intervals, out of 530 I shot in total, taken at 15- to 30-second intervals for the full time-lapse sequence included below.

A still-image composite with the lunar disks well separated will need shots only every 5 minutes, as I did above for the September 27, 2015 eclipse. 

Exposures for any lunar eclipse are tricky, whether you are shooting close-ups or wide-angles, because the Moon and sky change so much in brightness. 

As I did for the image below, for a still-image composite, you can expose just for the bright lunar disk and let the sky go dark.

Exposures for just the Moon will range from very short (about 1/500th second at f/8 and ISO 100) for the partials, to 1/2 to 2 seconds at f/2.8 to f/4 and ISO 400 for the totals, then shorter again (back to 1/500 at ISO 100) for the end shots when the Full Moon has returned to its normal brilliance. 

That’ll take constant monitoring and adjusting throughout the shoot, stepping the shutter speed gradually longer thorough the initial partial phase, then shorter again during the post-totality partial phase.

You’d then composite and layer (using a Lighten blend mode) the well-exposed disks (surrounded by mostly black sky) into another background image exposed longer for 10 to 30 seconds at ISO 800 to 1600 for the sky and stars, shot at mid-totality.

To maintain the correct relative locations of the lunar disks and foreground, the camera cannot move.

Lunar Eclipse Sequence from Monument Valley
The total lunar eclipse of April 4, 2015 taken from near Tear Drop Arch, in western Monument Valley, Utah. I shot the totality images during the short 4 minutes of totality. The mid-totality image is a composite of 2 exposures: 30 seconds at f/2.8 and ISO 1600 for the sky and landscape, with the sky brightening blue from dawn twilight, and 1.5 seconds at f/5.6 and ISO 400 for the disk of the Moon itself. Also, layered in are 26 short exposures for the partial phases, most being 1/125th sec at f/8 and ISO 400, with ones closer to totality being longer, of varying durations.

That technique works best if it’s just a still image you are after, such as above. This image is such a composite, of the April 4, 2015 total lunar eclipse from Monument Valley, Utah.

This type of composite takes good planning and proper exposures to pull off, but will be true to the scene, with the lunar disk and its motion shown to the correct scale and position as it was in the sky. It might be a composite, but it will be accurate.


My Rant! 

That’s in stark contrast to the flurry of ugly “faked” composites that will appear on the web by the end of the day on January 21, ones with huge telephoto Moons pasted willy-nilly onto a wide-angle sky.

Rather than look artistic, most such attempts look comically cut-and-pasted. They are amateurish. Don’t do it!  


Option 3: Advanced — Wide-Angle Time-Lapses

If it’s a time-lapse movie you want (see the video below), take exposures every 10 to 30 seconds, to ensure a final movie with smooth motion.

Unlike shooting for a still-image composite, for a time lapse each frame will have to be exposed well enough to show the Moon, sky, and landscape. 

That will require exposures long enough to show the sky and foreground during the partial phases — likely about 1 to 4 seconds at f/2.8 and ISO 400. In this case, the disk of the partially-eclipsed Moon will greatly overexpose, as it does toward the end of the above time-lapse from September 27, 2015.. 

But the Moon will darken and become better exposed during the late stages of the partial eclipse and during totality when a long exposure — perhaps now 10 to 20 seconds at f/2.8 and ISO 800 to 1600 — will record the bright red Moon amid the stars and winter Milky Way. 

Maintaining a steady cadence during the entire sequence requires using an interval long enough throughout to accommodate the expected length of the longest exposure at mid-totality, with similar camera settings to what you’ve used for other Milky Way nightscapes. If you’ve never taken those before, then don’t attempt this complex sequence. 

After totality, as the Moon and sky re-brighten, exposures will have to shorten again, and  symmetrically in reverse fashion for the final partial phases.

Such a time-lapse requires consistently and incrementally adjusting the camera over the three or more hours of the eclipse on a cold winter night. The high altitude of the Moon and its small size on the required wide angle lenses will make any final time lapse less impressive than at eclipses that occur when the Moon is rising or setting. 

But … the darkening of the sky and “turning on” of the Milky Way during totality will make for an interesting time-lapse effect. The sky and scene will be going from a bright fully moonlit night to effectively a dark moonless night, then back to moonlit. It’s a form of “holy grail” time lapse, requiring advanced processing with LRTimelapse software. 

Again, do not move the camera. Choose your lens and frame your camera to include the entire path of the Moon for as long as you plan to shoot. 

Even if the final movie looks flawed, individual frames should still produce good still images, or a composite built from a subset of the frames. 


Option 4: Simple — Telephoto Close-Ups

The first thought of many photographers is to shoot the eclipse with as long a telephoto lens as possible. That can work, but …

The harsh reality is that the Moon is surprisingly small (only 1/2-degree across) and needs a lot of focal length to do it justice, if you want a lunar close-up.

Telescope FOV-400 & 800mm

You’ll need a 300mm to 800mm lens. Unfortunately, the Moon and sky are moving and any exposures over 1/4 to 2 seconds (required during totality) will blur the Moon badly if its disk is large on the frame and all you are using is a fixed tripod.

If you don’t have a tracking mount, one solution is to keep the Moon’s disk small (using no more than a fast f/2 or f/2.8 135mm to 200mm lens) and exposures short by using a high ISO speed of 1600 to 3200. Frame the Moon beside the Beehive star cluster as I show below.

Take a range of exposures. But … be sure to focus!


TIP: Focus! And Focus Again!

Take care to focus precisely on a bright star using Live View. That’s true of any lens but especially telephotos and telescopes. 

Focus not just at the start of the night, but also more than once again later at night. Falling temperatures on a winter night will cause long lenses and telescopes to shift focus. What was sharp at the start of the eclipse won’t be by mid totality. 

The catch is that if you are shooting for a time-lapse or composite you likely won’t be able to re-point the optics to re-focus on a star in mid-eclipse. In that case, be sure to set up the gear well before you want to start shooing to let it cool to ambient air temperature. Now focus on a star, then frame the scene. Then hope the lens doesn’t shift off focus. You might be able to focus on the bright limb of the Moon but it’s risky.

Fuzzy images, not bad exposures, are the ruin of most attempts to capture a lunar eclipse, especially with a telephoto lens. And the Moon itself, especially during totality, is not a good target to focus on. Use a bright star. The winter sky has lots!


Option 5: Advanced — Tracked Telescopic Close-Ups 

If you have a mount that can be polar aligned to track the sky, then many more options are open to you. 

Sigma on SAM on Stars

You can use a telescope mount or one of the compact and portable trackers, such as the Sky-Watcher Star Adventurer (I show the Mini model above) or iOptron Sky Tracker units. While these latter units work great, you are best to keep the payload weight down and your lens size well under 300mm. 

Framing Telephoto CU

That’s just fine for this eclipse, as you really don’t need a frame-filling Moon. The reason is that the Moon will appear about 6 degrees west of the bright star cluster called the Beehive, or Messier 44, in Cancer.

As shown above, a 135mm to 200mm lens will frame this unique pairing well. For me, that will be the signature photo of this eclipse. The pairing can happen only at lunar eclipses that occur in late January, and there won’t be any more of those until 2037! 

That’s the characteristic that makes this eclipse rare and unique, not that it’s a “super-duper, bloody, wolf Moon!” But it doesn’t make for a catchy headline.

Total Lunar Eclipse, Dec 20, 2010 Total HDR
A High Dynamic Range composite of 7 exposures of the Dec 20/21, 2010 total lunar eclipse, from 1/2 second to 30 seconds, to show the more normally exposed eclipsed Moon with the star cluster M35, at left, in Gemini, to show the scene as it appeared in binoculars. Each tracked photo taken with a 77mm Borg apo refractor at f/4.2 (300mm focal length) and Canon 5D MkII at ISO 1600.

Exposures to show the star cluster properly might have to be long enough (30 to 120 seconds) that the Moon overexposes, even at mid-totality. If so, take different exposures for the Moon and stars, then composite them later, as I did above for the December 20, 2010 eclipse near the Messier 35 star cluster in Gemini. 

If really you want to shoot with even more focal length for framing just the Moon, a monster telephoto lens will work, but a small telescope such as an 80mm aperture f/6 to f/7 refractor will provide enough focal length and image size at much lower cost and lighter weight, and be easier to attach to a telescope mount. 

But even with a 500mm to 800mm focal length telescope the Moon fills only a small portion of the frame, though cropped frame cameras have the advantage here. Use one if it’s a big Moon you’re after! 

No matter the camera, the lens or telescope should be mounted on a solid equatorial telescope mount that you must polar align earlier in the night to track the sky. 

Alternatively, a motorized Go To telescope on an alt-azimuth mount will work, but only for single shots. The rotation of the field with alt-az mounts will make a mess of any attempts to shoot multiple-exposure composites or time-lapses, described below. 

Whatever the mount, for the sharpest lunar disks during totality, use the Lunar tracking rate for the motor. 

Total Lunar Eclipse Exposure Series
This series shows the need to constantly shift exposure by lengthening the shutter speed as the eclipse progresses. Do the same to shorten the exposure after totality. The exposures shown here are typical. 

Assuming an f-ratio of f/6 to f/8, exposures will vary from as short as 1/250th second at ISO 100 to 200 for the barely eclipsed Moon, to 4 to 20 seconds at ISO 400 to 1600 for the Moon at mid-totality. 

It’s difficult to provide a precise exposure recommendation for totality because the brightness of the Moon within the umbra can vary by several stops from eclipse to eclipse, depending on how much red sunlight manages to make it through Earth’s atmospheric filter to light the Moon.


TIP: Shoot for HDR

Total Lunar Eclipse, Dec 20, 2010 Partial HDR
Total eclipse of the Moon, December 20/21, 2010, with 5-inch refractor at f/6 (780mm focal length) and Canon 7D (cropped frame camera) at ISO 400. This is an HDR blend of 9 images from 1/125 second to 2 seconds, composited in Photoshop. Note  the blue tint along the shadow edge.

As I did above, during the deep partial phases an option is to shoot both long, multi-second exposures for the red umbra and short, split-second exposures for the bright part of the Moon not yet in the umbra.

Take 5 to 7 shots in rapid succession, covering the range needed, perhaps at 1-stop increments. Merge those later with High Dynamic Range (HDR) techniques and software, or with luminosity masks. 

Even if you’re not sure how to do HDR processing now, shoot all the required exposures anyway so you’ll have them when your processing skills improve. 


Option 6: Advanced — Close-Up Composites and Time-Lapses

With a tracking telescope on an equatorial mount you could fire shots every 10 to 30 seconds, and then assemble them into a time-lapse movie, as below. 

But as with wide-angle time-lapses, that will demand constant attention to gradually and smoothly shift exposures, ideally by 1/3rd-stop increments every few shots during the partial and total phases. Make lots of small adjustments, rather than fewer large ones.

If you track at the lunar rate, as I did above, the Moon should stay more or less centred while it drifts though the stars, assuming your mount is accurately polar aligned, an absolutely essential prerequisite here.  

Lunar Eclipse Composite
Composite image digitally created in Photoshop of images taken during October 27, 2004 total lunar eclipse, from Alberta Canada. Images taken through 5-inch apo refractor at f/6 with Canon Digital Rebel 300D camera at ISO 200.

Conversely, track at the sidereal rate and the stars will stay more or less fixed while the Moon drifts through the frame from right to left (west to east) as I show above in a composite of the October 27, 2004 eclipse.

But such a sequence takes even more careful planning to position the Moon correctly at the start of the sequence so it remains “in frame” for the duration of the eclipse, and ends up where you want at the end.

In the chart below, north toward Polaris is at the top of the frame. Position the Moon at the start of the eclipse so it ends up just above the centre of the frame at mid-eclipse. Tricky! 

Telescope CU-Stages
Repeated from earlier, this chart shows the path of the Moon through the north half of the umbra, a path that will be the same for any site, as will be the timing. North is up here.

As I show above, for this type of “Moon-thru-shadow” sequence a focal length of about 400mm is ideal on a full frame camera, or 300mm on a cropped frame camera.

From such a time-lapse set you could also use several frames selected from key stages of the eclipse, as I did in 2004, to make up a multiple-image composite showing the Moon moving through the Earth’s shadow. 

Again, planetarium software such as Starry Night I used above, which can be set to display the field of view of the camera and lens of your choice, is essential to plan the shoot. Don’t attempt it without the right software to plan the framing. 

I would consider the telescopic time-lapse method the most challenging of techniques. Considering the hour of the night and the likely cold temperatures, your best plan might be to keep it simple. 

It’s what I plan to do.

I’ll be happy to get a tracked telephoto close-up of the Moon and Beehive cluster as my prime goal, with a wide-angle scene of the eclipsed Moon beside Orion and the Milky Way as a bonus. A few telescope close-ups will be even more of a bonus.

Astrospheric
The Astrospheric website, with astronomy-oriented weather predictions. It’s also available as a great mobile app.

However, just finding clear skies might be the biggest challenge!

Try the Astrospheric app for astronomy-oriented weather predictions. The Environment Canada data it uses has led me to clear skies for several recent eclipses that other observers in my area missed. 

It’ll be worth the effort to chase!

The next total eclipse of the Moon anywhere on Earth doesn’t occur until May 26, 2021 in an event visible at dawn from Western North America. The next total lunar eclipse visible from all of North America comes a lunar year later, on May 15, 2022. 

Total Lunar Eclipse from Alan Dyer on Vimeo.

I leave you with a music video of the lunar eclipse of September 27, 2015 that incorporates still and time-lapse sequences shot using all of the above methods. 

Good luck and clear skies on eclipse night!

— Alan, January 1, 2019 / © 2019 Alan Dyer / amazingsky.com 

 

Happy Holidays to All!


Happy Holidays with a Rising Solstice Full Moon

Here’s a celestial greeting card to wish everyone Happy Holidays and clear skies for 2019!

It was a very clear night on December 22, with the Moon bright and yellow as it rose over the distant horizon of my backyard prairie landscape.

This was the Full Moon that fell on the day after the solstice (winter for the northern hemisphere).

Rising of the Solstice Full Moon
This is a close up with the 105mm refractor, the Astro-Physics Traveler, at f/5.8 for a focal length of 609mm, and with the Canon 6D MkII at ISO 200, with the camera on auto exposure and taken as part of a 950-frame time-lapse sequence. Click to zoom up to full screen.

Note that the Moon’s disk is rimmed with green at the top and red at the bottom, an effect due to atmospheric refraction. But it adds Christmas colours to the lunar orb, like an ornament in the sky.

Below is the time-lapse of the moonrise, shot through a telescope with a focal length of 600mm, so equivalent to a very long telephoto lens. The movie is in 4K. Enjoy! And …

… All the best for 2019!

And don’t forget, you can get my free 2019 Amazing Sky Calendar at my website at http://www.amazingsky.com/aboutalan.html

Scroll down for the free PDF you can print out locally as you like.

2019 Amazing Sky Calendar Cover

Cheers and Happy Holidays!

— Alan, December 22, 2018 / AmazingSky.com 

 

 

Follow Comet Wirtanen


Comet Wirtanen / 46P on December 6, 2018

A well-known comet is making its closest approach to Earth in many years and promises a good show. 

Comet Wirtanen is now climbing up the late autumn and winter sky for northern hemisphere viewers, and is already a fine binocular comet. By mid-December it might be bright enough to be visible to the naked eye, but only from a dark rural site.

Discovered in 1948 by Carl Wirtanen at the Lick Observatory, his namesake comet orbits the Sun every 5.4 years. So unlike other recent bright comets that have visited us for the first time, Comet Wirtanen (aka 46P) is well known. It is one of many “Jupiter-family” comets whose orbits have been shaped by the gravity of Jupiter and orbit the Sun about every 6 years.

So since it was discovered, Comet 46P (the 46th comet in the catalog of periodic comets) has been well observed. It isn’t better known because at most returns it never gets bright, and that’s because it never gets closer to the Sun than a little more than the distance from the Earth to the Sun. (Its perihelion distance is 1.06 AU, with 1 AU, or Astronomical Unit, being the average distance from Earth to the Sun.)

However, despite this, we’re expecting – indeed already enjoying – a good show at this return.

Due to the quirk of orbital clockwork, on this return the comet reaches its closest point to the Sun just before it is also closest to Earth.

That puts the comet “just” 11,680,000 kilometres from us at its closest approach to Earth on December 16, four days after perihelion, the point when the comet is closest to the Sun.

Comet Wirtanen from Space
The relative position of the Sun, Earth and Comet Wirtanen on December 16, 2018.

Comet Wirtanen will be relatively bright simply by virtue of its proximity.

But it is also an active comet, emitting a lot of gas and dust into a large “coma,” and that’s what we see, not the 1-kilometre-wide icy nucleus itself which is too small and shrouded by the coma. (As a footnote, Comet Wirtanen was to have been the comet that the European Rosetta probe was to visit, but launch delays forced ESA to switch cometary targets.)

Comet Wirtanen is glowing at magnitude 5 to 6, technically making it visible to the naked eye. However, because it is large and diffuse, in practice you need binoculars to see it – now.

But as it approaches Earth and the Sun, Wirtanen will brighten, perhaps to magnitude 3 (the brightest stars are magnitude 0 to 1), making it easier to see with the unaided eye from a dark site.

The one catch is that as it heads toward its brightest in mid-December the waxing Moon also begins to enter the sky and wash out the comet with moonlight.


The first two weeks of December will be prime time for Wirtanen


Comet Wirtanen Path
The path of Comet Wirtanen across the sky in December 2018. The yellow dots mark the position of the comet at nightly intervals for late evening (10 p.m.) for North America. While comet will be in the sky most of the night, it will be highest in late evening about 10 p.m. local time when the sky will look as depicted, with the comet high in the south to southeast. Click or tap to download a full-sized version.

The first two weeks of December will be prime time for Wirtanen, with a particularly good opportunity coming on the evenings of December 15 and 16 when it shines below the Pleiades star cluster. The gibbous Moon will set about 1 to 2 a.m. with the comet still high enough for a dark sky view and photos.

Those will be great nights to shoot the comet and the cluster with a telephoto lens, provided the camera is on a tracker for untrailed exposures of 1 to 4 minutes. A 135mm to 300mm lens will frame the pair well.

Winter Green Comet with Orion
Comet Wirtanen as a green glow at upper right here in Eridanus. and well to the west of Orion, rising here at left, on the evening of December 6, 2018. I shot this with a wide-angle 35mm lens in a blend of tracked and untracked 1-minute exposures.

After that, through late December, the bright Moon will interfere with  the view. For example, a close approach of the comet near the star Capella on December 23 happens with the nearly Full Moon not far away.

Comet Wirtanen / 46P on December 6, 2018
Comet Wirtanen in a close-up through a telescope on December 6, 2018 in a stack of short and long exposures.

I took the above close-up photo of Comet Wirtanen on December 6. It is a long-exposure telescopic view, but the comet is easy to see with binoculars. It appears visually and photographically as a diffuse fuzzball, with the camera recording a vivid cyan colour from glowing cyanogen and diatomic carbon molecules. You won’t see that colour with your eyes, even in a telescope.

Comet Wirtanen Path Dec 8 to 16
The path of Comet Wirtanen Dec 8 to 16 superimposed on an actual sky image with the comet taken December 8. The circle indicates the field of view of typical binoculars. On Dec 15 and 16 the comet will be in the same binocular field as the Pleiades star cluster. The positions are for about 10 pm Mountain Standard Time for each of those dates.

Even at the comet’s best in mid-December any tail might be hard to see and even photograph (it appears faintly above) as it will be both faint and pointed directly away from us because, as comet tails do, it will also be pointed away from the Sun.

Look for a large glow which will be grey to the eye but green to the camera.

While you can just take pictures for yourself, astronomers are asking amateur astrophotographers to participate in a worldwide observing campaign to monitor Comet Wirtanen. More details are available here at wirtanen.astro.umd.edu and at http://aop.astro.umd.edu/

Clear skies and happy comet hunting!

— Alan, November 30, 2018 (Revised December 6) / © 2018 Alan Dyer / AmazingSky.com 

Testing ON1 Photo RAW for Astrophotography


ON1 Testing Title

Can the new version of ON1 Photo RAW match Photoshop for astrophotography? 

The short TL;DR answer: No.

But … as always, it depends. So do read on.


Released in mid-November 2018, the latest version of ON1 Photo RAW greatly improves a non-destructive workflow. Combining Browsing, Cataloging, Raw Developing, with newly improved Layers capabilities, ON1 is out to compete with Adobe’s Creative Cloud photo suite – Lightroom, Camera Raw, Bridge, and Photoshop – for those looking for a non-subscription alternative.

Many reviewers love the new ON1 – for “normal” photography.

But can it replace Adobe for night sky photos? I put ON1 Photo RAW 2019 through its paces for the demanding tasks of processing nightscapes, time-lapses, and deep-sky astrophotos.


The Conclusions

In my eBook “How to Photograph and Process Nightscapes and Time-Lapses” (linked to at right) I present dozens of processing tutorials, including several on how to use ON1 Photo RAW, but the 2018 edition. I was critical of many aspects of the old version, primarily of its destructive workflow when going from its Develop and Effects modules to the limited Layers module of the 2018 edition.

I’m glad to see many of the shortfalls have been addressed, with the 2019 edition offering a much better workflow allowing layering of raw images while maintaining access to all the original raw settings and adjustments. You no longer have to flatten and commit to image settings to layer them for composites. When working with Layers you are no longer locked out of key functions such as cropping.

I won’t detail all the changes to ON1 2019 but they are significant and welcome.

The question I had was: Are they enough for high-quality astrophotos in a non-destructive workflow, Adobe Photoshop’s forté.

While ON1 Photo RAW 2019 is much better, I concluded it still isn’t a full replacement of Adobe’s Creative Cloud suite, as least not for astrophotography.

NOTE: All images can be downloaded as high-res versions for closer inspection. 


ON1 2019 is Better, But for Astrophotography …

  1. Functions in Layers are still limited. For example, there is no stacking and averaging for noise smoothing. Affinity Photo has those.
  2. Filters, though abundant for artistic special effect “looks,” are limited in basic but essential functions. There is no Median filter, for one.
  3. Despite a proliferation of contrast controls, for deep-sky images (nebulas and galaxies) I was still not able to achieve the quality of images I’ve been used to with Photoshop.
  4. The lack of support for third-party plug-ins means ON1 cannot work with essential time-lapse programs such as Timelapse Workflow or LRTimelapse.
ON1 Final Composite
A finished nightscape composite, with stacked exposures for the ground and stacked and tracked exposures for the sky, layered and blended in ON1.

Recommendations

Nightscapes: ON1 Photo RAW 2019 works acceptably well for nightscape still images:

  1. Its improved layering and excellent masking functions are great for blending separate ground and sky images, or for applying masked adjustments to selected areas.

Time-Lapses: ON1 works is just adequate for basic time-lapse processing:

  1. Yes, you can develop one image and apply its settings to hundreds of images in a set, then export them for assembly into a movie. But there is no way to vary those settings over time, as you can by mating Lightroom to LRTimelapse.
  2. As with the 2018 edition, you still cannot copy and paste masked local adjustments from image to image, limiting their use.
  3. Exporting those images is slow.

Deep-Sky: ON1 is not a program I can recommend for deep-sky image processing:

  1. Stars inevitably end up with unsightly sharpening haloes.
  2. De-Bayering artifacts add blocky textures to the sky background.
  3. And all the contrast controls still don’t provide the “snap” and quality I’m used to with Photoshop when working with low-contrast subjects.

Library / Browse Functions

ON1 Browse Module
ON1 cannot catalog or display movie files or Photoshop’s PSB files (but then again with PSBs neither can Lightroom!).

ON1 is sold first and foremost as a replacement for Adobe Lightroom, and to that extent it can work well. Unlike Lightroom, ON1 allows browsing and working on images without having to import them formally into a catalog.

However, you can create a catalog if you wish, one that can be viewed even if the original images are not “on-line.” The mystery seems to be where ON1 puts its catalog file on your hard drive. I was not able to find it, to manually back it up. Other programs, such as Lightroom and Capture One, locate their catalogs out in the open in the Pictures folder.

For those really wanting a divorce from Adobe, ON1 now offers an intelligent AI-based function for importing Lightroom catalogs and transferring all your Lightroom settings you’ve applied to raw files to ON1’s equivalent controls.

However, while ON1 can read Photoshop PSD files, it will flatten them, so you would lose access to all the original image layers.

ON1’s Browse module is good, with many of the same functions as Lightroom, such as “smart collections.” Affinity Photo – perhaps ON1’s closest competitor as a Photoshop replacement – still lacks anything like it.

But I found ON1’s Browse module buggy, often taking a long while to allow access into a folder, presumably while it is rendering image previews.

There are no plug-ins or extensions for exporting directly to or synching to social media and photo sharing sites.


Nightscape Processing – Developing Raw Images

ON1 Before and After Processing
On the left, a raw image as it came out of the camera. On the right, after developing (with Develop and Effects module settings applied) in ON1.

For this test I used the same nightscape image I threw at Adobe competitors a year ago, in a test of a dozen or more raw developers. It is a 2-minute tracked exposure with a Sigma 20mm Art lens at f/2 and Nikon D750 at ISO 1600.

ON1 did a fairly good job. Some of its special effect filters, such a Dynamic Contrast, Glow, and Sunshine, can help bring out the Milky Way, though do add an artistic “look” to an image which you might or might not like.

Below, I compare Adobe Camera Raw (ACR) to ON1. It was tough to get ON1’s image looking the same as ACR’s result, but then again, perhaps that’s not the point. Does it just look good? Yes, it does.

ON1 & ACR Raw Image Comparison
On the left, a single raw image developed with Adobe Camera Raw. On the right, the same image with ON1 and its basic Develop and more advanced Effects settings.

Compared to Adobe Camera Raw, which has a good array of basic settings, ON1 has most of those and more, in the form of many special Effects, with many combined as one-click Presets, as shown below.

ON1 Presets
ON1 offers a huge array of Presets that apply combinations of its filters with one click from the Browse module.

A few presets and individual filters – the aforementioned Dynamic Contrast and Glow – are valuable. However, most of ON1’s filters and presets will not be useful for astrophotography, unless you are after highly artistic and unnatural effects.

Noise Reduction and Lens Correction

ON1 Noise Reduction
On the left, an image in ON1 without any Noise Reduction. On the right, with noise reduction and sharpening (under Details) applied with the settings shown.

Critical to all astrophotography is excellent noise reduction. ON1 does a fine job here, with good smoothing of noise without harming details.

Lens Correction works OK. It detected the 20mm Sigma art lens and automatically applied distortion correction, but not any vignetting (light “fall-off”) correction, perhaps the most important correction in nightscape work. You have to dial this in manually by eye, a major deficiency.

By comparison, ACR applies both distortion and vignetting correction automatically. It also includes settings for many manual lenses that you can select and apply in a click. For example, ACR (and Lightroom) includes settings for popular Rokinon and Venus Optics manual lenses; ON1 does not.

Hot Pixel Removal

Hot Pixel Removal Comparison
On the left, ACR with noise reduction applied (it offers no user-selectable Hot Pixel Removal tool). In the middle, ON1 with Remove Hot Pixels turned on; on the right, with it turned off – showing more hot pixels than ACR does.

I shot the example image on a warm summer night and without using in-camera Long Exposure Noise Reduction (to keep the gap between exposures short when shooting sets of tracked and untracked exposures for later compositing).

However, the penalty for not using LENR to expedite the image taking is a ground filled with hot pixels. While Adobe Camera Raw does have some level of hot pixel removal working “under the hood,” many specks remained.

ON1 showed more hot pixels, until you clicked Remove Hot Pixels, found under Details. As shown at centre above, it did a decent job getting rid of the worst offenders.

But as I’ll show later, the penalty is that stars now look distorted and sometimes double, or you get the outright removal of stars. ON1 doesn’t do a good job distinguishing between true sharp-edged hot pixels and the softer images of stars. Indeed, it tends to over sharpen stars.

A competitor, Capture One 11, does a better job, with an adjustable Single Pixel removal slider, so you can at least select the level of star loss you are willing to tolerate to get rid of hot pixels.

Star Image Quality

ON1 & ACR Star Image Comparison
On the left, a 700% blow-up of the stars in Adobe Camera Raw. On the right, the same image processed in ON1 and exported out as a PSD.

Yes, we are pixel peeping here, but that’s what we do in astrophotography. A lot!

Stars in ON1 don’t look as good as in Camera Raw. Inevitably, as you add contrast enhancements, stars in ON1 start to exhibit dark and unsightly “sharpening haloes” not present in ACR, despite me applying similar levels of sharpening and contrast boosts to each version of the image.

Camera Raw has been accused of producing images that are not as sharp as with other programs such as Capture One and ON1.

There’s a reason. Other programs over-sharpen, and it shows here.

We can get away with it here in wide-field images, but not later with deep-sky close-ups. I don’t like it. And it is unavoidable. The haloes are there, albeit at a low level, even with no sharpening or contrast enhancements applied, and no matter what image profile is selected (I used ON1 Standard throughout).

De-Bayering Artifacts

ON1-Debayer
ON1, with contrast boosts applied but with no sharpening or noise reduction, shows star haloes, while the sky shows a blocky pattern at the pixel level in high ISO shots.
ACR-Debayer
Adobe Camera Raw, with similar settings but also no sharpening or noise reduction, shows a smooth and uniform sky background.

You might have to download and closely inspect these images to see the effect, but ON1’s de-Bayering routine exhibits a cross-hatched blocky pattern at the pixel-peeping level. ACR does not.

I see this same effect with some other raw developers. For example, the free Raw Therapee shows it with many of its choices for de-Bayering algorithms, but not all. Of the more than a dozen raw developers I tested a year ago, ACR and DxO PhotoLab had (and still have) the most artifact-free de-Bayering and smoothest noise reduction

Again, we can get away with some pixel-level artifacts here, but not later, in deep-sky processing.


Nightscape Processing — Layering and Compositing

ON1 Perfect Brush
ON1’s adjustable “Perfect Brush” option for precise masking around edges and objects isn’t quite as effective as Photoshop’s Quick Selection Tool.

Compositing

The 2018 version of ON1 forced you to destructively flatten images when bringing them into the Layers module.

The 2019 version of ON1 improves that. It is now possible to composite several raw files into one image and still retain all the original Develop and Effects settings for non-destructive work.

You can then use a range of masking tools to mask in or out the sky.

For the example above, I have stacked tracked and untracked exposures, and am starting to mask out the trailed stars from the untracked exposure layer.

To do this with Adobe, you would have to open the developed raw files in Photoshop (ideally using “smart objects” to retain the link back to the raw files). But with ON1 we stay within the same program, to retain access to non-destructive settings. Very nice!

To add masks, ON1 2019 does not have the equivalent of Photoshop’s excellent Quick Selection Tool for selecting the sky or ground. It does have a “Perfect Brush” option which uses the tonal value of the pixels below it, rather than detecting edges, to avoid “painting over the lines.”

While the Perfect Brush does a decent job, it still requires a lot of hand painting to create an accurate mask without holes and defects. There is no non-destructive “Select and Mask” refinement option as in Photoshop.

Yes, ON1’s Refine Brush and Chisel Mask tools can help clean up a mask edge but are destructive to the mask. That’s not acceptable to my non-destructive mindset!

Local Adjustments 

ON1 Masking Adjustments
Local Adjustments can be painted in or out with classic and easy-to-adjust and view masks and layers, rather than adjustment pins used by many raw developers such as ACR.

The masking tools are also applicable to adding “Local Adjustments” to any image layer, to brighten or darken regions of an image for example.

These work well and I find them more intuitive than the “pins” ACR uses on raw files, or DxO PhotoLab’s quirky “U-Point” interface.

ON1’s Local Adjustments work more like Photoshop’s Adjustment Layers and are similarly non-destructive. Excellent.

Luminosity Masks

ON1 Luminosity Masking
ON1 has one-click Luminosity masking, an excellent feature.

A very powerful feature of ON1 is its built-in Luminosity masking.

Yes, Camera Raw now has Range Masks, and Photoshop can be used to create luminosity masks, but making Photoshop’s luminosity masks easily adjustable requires purchasing third-party extension panels.

ON1 can create an adjustable and non-destructive luminosity mask on any image or adjustment layer with a click.

While such masks, based on the brightness of areas, aren’t so useful for low-contrast images like the Milky Way scene above, they can be very powerful for merging high-contrast images (though ON1 also has an HDR function not tested here).

Glow Effect
ON1’s handy Orton-style Glow effect, here with a Luminosity mask applied. The mask can be adjusted with the Levels and Window sliders, and applied to a range of colors as well.

ON1 has the advantage here. Its Luminosity masks are a great feature for compositing exposures or for working on regions of bright and dark in an image.

Final Composite

ON1 Final Composite
A finished nightscape composite, with stacked exposures for the ground and stacked and tracked exposures for the sky, layered and blended in ON1.

Here again is the final result, above.

It is not just one image each for the sky and ground, but is instead a stack of four images for each half of the composite, to smooth noise. This form of stacking is somewhat unique to astrophotography, and is commonly used to reduce noise in nightscapes and in deep-sky images, as shown later.

Stacking

ON1-Layer Opacities
This shows an intermediate step in creating the final composite shown above: Four sky layers are stacked, with opacities as shown, which has the effect of smoothing noise. But to continue working on the image requires making a single “New Stamped Layer” out of the group of four – in this case, the sky layers. The same can be done for the four ground layers.

Here I show how you have to stack images in ON1.

Unlike Photoshop and Affinity Photo, ON1 does not have the ability to merge images automatically into a stack and apply a mathematical averaging to the stack, usually a Mean or Median stack mode. The averaging of the image content is what reduces the random noise.

Instead, with ON1 you have perform an “old school” method of average stacking – by changing the opacity of the layers, so that Layer 2 = 50%, Layer 3 = 33%, Layer 4 = 25%, and so on. The result is identical to performing a Mean stack mode in Photoshop or Affinity.

Fine, except there is no way to perform a Median stack, which can be helpful for eliminating odd elements present in only one frame, perhaps an aircraft trail.

Copy and Paste Settings

ON1 Pasting Settings
ON1 allows easy copying and pasting of settings from one raw image to others, with the annoying exception of Local Adjustments and their masks.

Before we even get to the stacking stage, we have to develop and process all the images in a set. Unlike Lightroom or Camera Raw, ON1 can’t develop and synchronize settings to a set of images at once. You can work on only one image at a time.

So, you work on one image (one of the sky images here), then Copy and Paste its settings to the other images in the set. I show the Paste dialog box here.

This works OK, though I did find some bugs – the masks for some global Effects layers did not copy properly; they copied inverted, as black instead of white masks.

However, Luminosity masks did copy from image to image, which is surprising considering the next point.

The greater limitation is that no Local Adjustments (ones with masks to paint in a correction to a selected area) copy from one image to another … except ones with gradient masks. Why the restriction?

So as wonderful as ON1’s masking tools might be, they aren’t of any use if you want to copy their masked adjustments across several images, or, as shown next, to a large time-lapse set.

While Camera Raw’s and Lightroom’s Local Adjustment pins are more awkward to work with, they do copy across as many images as you like.


Time-Lapse Processing

ON1 Copy & Paste
ON1 does allow developing one image in a set, then copying and pasting its settings to perhaps hundreds of other images in a time-lapse set.

A few Adobe competitors, such as Affinity Photo (as of this writing) simply can’t do this.

By comparison, with the exception of Local Adjustments, ON1 does have good functions for Copying and Pasting Settings. These are essential for processing a set of hundreds of time-lapse frames.

ON1 Export
This is ON1’s Export dialog box, set up here to export the developed raw files into another “intermediate” set of 4K-sized JPGs for movie assembly.

Once all the images are processed – whether it be with ON1 or any other program – the frames have to exported out to an intermediate set of JPGs for assembly into a movie by third-party software. ON1 itself can’t assemble movies, but then again neither can Lightroom (as least not very well), though Photoshop can, through its video editing functions.

For my test set of 220 frames, each with several masked Effects layers, ON1 took 2 hours and 40 minutes to perform the export to 4K JPGs. Photoshop, through its Image Processor utility, took 1 hour and 30 minutes to export the same set, developed similarly and with several local adjustment pins.

ON1 did the job but was slow.

A greater limitation is that, unlike Lightroom, ON1 does not accept any third party plug-ins (it serves as a plug-in for other programs). That means ON1 is not compatible with what I feel are essential programs for advanced time-lapse processing: either Timelapse Workflow (from https://www.timelapseworkflow.com) or the industry-standard LRTimelapse (from https://lrtimelapse.com).

Both programs work with Lightroom to perform incremental adjustments to settings over a set of images, based on the settings of several keyframes.

Lacking the ability to work with these programs means ON1 is not a program for serious and professional time-lapse processing.


Deep-Sky Processing

ON1-Tracked Milky Way
A tracked 2-minute exposure of the Cygnus Milky Way, with a Sony a7III camera at ISO 800 and Venus Optics Laowa 15mm lens at f/2, developed in ON1.
ACR-Tracked Milky Way
The same Milky Way image developed in Adobe Camera Raw. It looks better!

Wide-Angle Milky Way

Now we come to the most demanding task: processing long exposures of the deep-sky, such as wide-angle Milky Way shots and close-ups of nebulas and galaxies taken through telescopes. All require applying generous levels of contrast enhancement.

As the above example shows, try as I might, I could not get my test image of the Milky Way to look as good with ON1 as it did with Adobe Camera Raw. Despite the many ways to increase contrast in ON1 (Contrast, Midtones, Curves, Structure, Haze, Dynamic Contrast and more!), the result still looked flat and with more prominent sky gradients than with ACR.

And remember, with ACR that’s just the start of a processing workflow. You can then take the developed raw file into Photoshop for even more precise work.

With ON1, its effects and filters all you have to work with. Yes, that simplifies the workflow, but its choices are more limited than with Photoshop, despite ON1’s huge number of Presets.

Deep-Sky Close-Ups

ON1 Processed M31
The Andromeda Galaxy, in a stack of six tracked and auto-guided 8-minute exposures with a stock Canon 6D MkII through an 80mm f/6 refractor.
Photoshop Processed M31
The same set of six exposures, stacked and processed with ACR and Photoshop, with multiple masked adjustment layers as at right. The result looks better.

Similarly, taking a popular deep-sky subject, the Andromeda Galaxy, aka M31, and processing the same original images with ON1 and ACR/Photoshop resulted in what I think is a better-looking result with Photoshop.

Of course, it’s possible to change the look of such highly processed images with the application of various Curves and masked adjustment layers. And I’m more expert with Photoshop than with ON1.

But … as with the Cygnus Milky Way image, I just couldn’t get Andromeda looking as good in ON1. It always looked a little flat.

Dynamic Contrast did help snap up the galaxy’s dark lanes, but at the cost of “crunchy” stars, as I show next. A luminosity “star mask” might help protect the stars, but I think the background sky will inevitably suffer from the de-Bayering artifacts.

Star and Background Sky Image Quality

ON1 Processed M31-Close-Up
A 400% close-up of the final Andromeda Galaxy image. It shows haloed stars and a textured and noisy sky background.
Photoshop Processed M31-Close-Up
The same area blown up 400% of the Photoshop version of the Andromeda Galaxy image. Stars and sky look smoother and more natural.

As I showed with the nightscape image, stars in ON1 end up looking too “crunchy,” with dark halos from over sharpening, and also with the blocky de-Bayering artifacts now showing up in the sky.

I feel it is not possible to avoid dark star haloes, as any application of contrast enhancements, so essential for these types of objects, brings them out, even if you back off sharpening at the raw development stage, or apply star masks.

ON1 Processed M31-With & Without
On the left, the image before any processing applied; on the right, after the level of processing needed for such deep-sky images. What starts out looking OK, turns messy.

ON1 is applying too much sharpening “under the hood.” That might “wow” casual daytime photographers into thinking ON1 is making their photos look better, but it is detrimental to deep-sky images. Star haloes are a sign of poor processing.

Noise and Hot Pixels

ON1 With & Without NR and Hot Pixels
With and without noise reduction and hot pixel removal shows stars becoming lost and misshapen with the Remove Hot Pixel option.

ON1’s noise reduction is quite good, and by itself does little harm to image details.

But turn on the Remove Hot Pixel button and stars start to be eaten. Faint stars fade out and brighter stars get distorted into double shapes or have holes in them.

Hot pixel removal is a nice option to have, but for these types of images it does too much harm to be useful. Use LENR or take dark frames, best practices in any case.

Image Alignment and Registration

ON1 Auto-Alignment
The six Andromeda images stacked then “Auto-Aligned” in ON1, with just the top (first) and bottom (last) images turned on here. with the top image switched to Difference blend mode to show any mis-alignment.
Photoshop Auto-Alignment
The same set stacked and “Auto-Aligned” in Photoshop, with the same first and last images turned on and blended with Difference. PS’s alignment is much better, indicated by the image “blacking out” as the two registered frames cancel out.

Before any processing of deep-sky images is possible, it is first necessary to stack and align them, to make up for slight shifts from image to image, usually due to the mount not being perfectly polar aligned. Such shifts can be both translational (left-right, up-down) and rotational (turning about the guide star).

New to ON1 2019 is an Auto-Align Layers function. It worked OK but not nearly as well as Photoshop’s routine. In my test images of M31, ON1 didn’t perform enough rotation.

Once stacked and aligned, and as I showed above, you then have to manually change the opacities of each layer to blend them for noise smoothing.

By comparison, Photoshop has a wonderful Statistics script (under File>Scripts) that will automatically stack, align, then mean or median average the images, and turn the result into a non-destructive smart object, all in one fell swoop. I use it all the time for deep-sky images. There’s no need for separate programs such as Deep-Sky Stacker.

In ON1, however, all that has to be done manually, step-by-step. ON1 does do the job, just not as well.


Wrap-Up

M31 from ON1
The final M31, Andromeda Galaxy image processed with ON1.

ON1 Photo RAW 2019 is a major improvement, primarily in providing a more seamless and less destructive workflow.

Think of it as Lightroom with Layers! 

But it isn’t Photoshop.

Dynamic Contrast
ON1’s useful Dynamic Contrast filter. A little goes a long way.

True to ON1’s heritage as a special effect plug-in, it has some fine Effect filters, such as Dynamic Contrast above, ones I sometimes use from within Photoshop as plug-in smart filters.

Under Sharpen, ON1 does offer a High Pass option, a popular method for sharpening deep-sky objects.

Missing Filters and Adjustments

But for astrophoto use, ON1 is missing a lot of basic but essential filters for pixel-level touch-ups. Here’s a short list:

• Missing are Median, Dust & Scratches, Radial Blur, Shake Reduction, and Smart Sharpen, just to mention a handful of filters I find useful for astrophotography, among the dozens of others Photoshop has, but ON1 does not. But then again, neither does Lightroom, another example of how ON1 is more light Lightroom with layers and not Photoshop.

ON1 Color Adjustment
ON1’s selective Color Adjustment. OK, but where’s the Black and Neutrals?

• While ON1 has many basic adjustments for color and contrast, its version of Photoshop’s Selective Color lacks Neutral or Black sliders, great for making fine changes to color balance in astrophotos.

• While there is a Curves panel, it has no equivalent to Photoshop’s “Targeted Adjustment Tool” for clicking on a region of an image to automatically add an inflection point at the right spot on the curve. This is immensely useful for deep-sky images.

• Also lacking is a basic Levels adjustment. I can live without it, but most astrophotographers would find this a deal-breaker.

• On the other hand, hard-core deep-sky photographers who do most of their processing in specialized programs such as PixInsight, using Photoshop or Lightroom only to perform final touch-ups, might find ON1 perfectly fine. Try it!

Saving and Exporting

ON1 saves its layered images as proprietary .onphoto files and does so automatically. There is no Save command, only a final Export command. As such it is possible to make changes you then decide you don’t like … but too late! The image has already been saved, writing over your earlier good version. Nor can you Save As … a file name of your choice. Annoying!

Opening a layered .onphoto file (even with ON1 itself already open) can take a minute or more for it to render and become editable.

Once you are happy with an image, you can Export the final .onphoto version as a layered .PSD file but the masks ON1 exports to the Photoshop layers may not match the ones you had back in ON1 for opacity. So the exported .PSD file doesn’t look like what you were working on. That’s a bug.

Only exporting a flattened TIFF file gets you a result that matches your ON1 file, but it is now flattened.

Bugs and Cost

I encountered a number of other bugs, ones bad enough to lock up ON1 now and then. I’ve even seen ON1’s own gurus encounter bugs with masking during their live tutorials. These will no doubt get fixed in 2019.x upgrades over the next few months.

But by late 2019 we will no doubt be offered ON1 Photo RAW 2020 for another $80 upgrade fee, over the original $100 to $120 purchase price. True, there’s no subscription, but ON1 still costs a modest annual fee, presuming you want the latest features.

Now, I have absolutely no problem with that, and ON1 2019 is a significant improvement.

However, I found that for astrophotography it still isn’t there yet as a complete replacement for Adobe.

But don’t take my word for it. Download the trial copy and test it for yourself.

— Alan, November 22, 2018 / © 2018 Alan Dyer/AmazingSky.com 

 

Aurora Reflections in Yellowknife


Auroral Arc over Tibbitt Lake

The Northern Lights are amazing from Yellowknife, in Canada’s Northwest Territories. 

A handful of locations in the world are meccas for aurora chasers. Yellowknife is one of them and, for me, surprisingly accessible with daily flights north.

In a two-hour flight from Calgary you can be at latitude 62° North and standing under the auroral oval with the lights dancing overhead every clear night.

Aurora Panorama at Tibbit Lake #2

The attraction of going in early September, as I did, is that the more persistent clouds of late autumn have not set in, and the many lakes and rivers are not yet frozen, making for superb photo opportunities.

Lakes down Highway 4, the Ingraham Trail, such as Prosperous, Prelude, and Pontoon are popular spots for the busloads of tourists who fly in every year from around the world.

On one magical night I and my local host and guide, Stephen Bedingfield, went to the end of the Trail, to where the Ice Road begins, to Tibbitt Lake, and had the site to ourselves. The aurora was jaw-dropping that night.

On other nights with less certain prospects I stayed in town, and still got a fine show on several nights, the Lights so bright they show up well even from within urban Yellowknife.

On another night we chased into clear skies down Highway 3 to the west, to a rocky plateau on the Canadian Precambrian Shield. Even amid the clouds, the aurora was impressive.

Aurora in the Clouds Panorama

But it was the night at Tibbitt that was the highlight.

Here is the finale music video from movies shot that night, September 8, 2018, with two cameras: the Sony a7III used to take “real-time” 4K videos of the aurora motion, and the Nikon D750 used to take time-lapses.

The movie is in 4K. The music, Eternal Hope, is by Steven Gutheinz and is used by permission of West One Music.

Aurora Reflections from Alan Dyer on Vimeo.

Click through to Vimeo for more technical info about the video.

Enjoy! And do share!

And make Yellowknife one of your bucket-list locations.

— Alan, October 2, 2018 / © 2018 Alan Dyer / AmazingSky.com