How to Photograph Comet NEOWISE


Comet over Hoodoos at Dinosaur Park in Twilight (July 14, 2020)A bright comet is a once-a-decade opportunity to capture some unique nightscapes. Here are my suggested tips and FAQs for getting your souvenir shot. 

My guide to capturing Comet NEOWISE assumes you’ve done little, if any, nightscape photography up to now. Even for those who have some experience shooting landscape scenes by night, the comet does pose new challenges — for one, it moves from night to night and requires good planning to get it over a scenic landmark. 

So here are my tips and techniques, in answers to the most frequently asked questions I get and that I see on social media posts.

Comet over Hoodoos at Dinosaur Park (July 14, 2020)
Comet NEOWISE (C/2020 F3) over the eroded hoodoo formations at Dinosaur Provincial Park, Alberta, July 14-15, 2020. A faint aurora is at right. The foreground is lit by starlight only; there was no light painting employed here. This is a stack of 12 exposures for the ground to smooth noise, blended with a single untracked exposure of the sky, all at 20 seconds at f/2.8 and ISO 1600, all with the 35mm Canon lens and Canon 6D MkII camera.

How Long Will the Comet be Visible?

The comet is not going to suddenly whoosh away or disappear. It is in our northern hemisphere sky and fairly well placed for shooting and watching all summer.

But … it is now getting fainter each night so the best time to shoot it is now! Or as soon as clouds allow on your next clear night. 

As of this writing on July 18 it is still bright enough to be easily visible to the unaided eye from a dark site. How long this will be the case is unknown. 

But after July 23 and its closest approach to Earth the comet will be receding from us and that alone will cause it to dim. Later this summer it will require binoculars to see, but might still be a good photogenic target, but smaller and dimmer than it was in mid-July. 

Comet Path
This chart shows the position of Comet NEOWISE at nightly intervals through the rest of the summer. However, the rest of July are the prime nights left for catching the comet at its best. Click or tap on the image to download a full-res copy.

When is the Best Time to Shoot?

The comet has moved far enough west that it is now primarily an evening object. So look as soon as it gets dark each night. 

Until later in July it is still far enough north to be “circumpolar” for northern latitudes (above 50° N) and so visible all night and into the dawn. 

But eventually the comet will be setting into the northwest even as seen from northern latitudes and only visible in the evening sky. Indeed, by the end of July the comet will have moved far enough south that observers in the southern hemisphere anxious to see the comet will get their first looks. 

Comet NEOWISE over Red Deer River
Comet NEOWISE (C/2020 F3) over the Red Deer River from Orkney Viewpoint north of Drumheller, Alberta, on the morning of July 11, 2020. The sky is brightening with dawn twilight and a small display of noctilucent clouds is on the horizon at right. This is a two-segment vertical panorama with the 35mm Canon lens at f/2.8 and Canon 6D MkII at ISO 200 for 13 seconds each. Stitched with Adobe Camera Raw.

Where Do I Look? 

In July look northwest below the Big Dipper. By August the comet is low in the west below the bright star Arcturus. By then it will be moving much less from night to night. The chart above shows the comet at nightly intervals; you can see how its nightly motion slows as it recedes from us and from the Sun. 

Selfie Observing Comet NEOWISE (July 15, 2020)
A selfie observing Comet NEOWISE (C/2020 F3) with binoculars on the dark moonless night of July 14/15, 2020 from Dinosaur Provincial Park, Alberta. A faint aurora colours the sky green and magenta. The faint blue ion tail of the comet is visible in addition to its brighter dust tail. The ground is illuminated by starlight and aurora light only. This is a blend of 6 exposures stacked for the ground (except me) to smooth noise, and one exposure for the sky and me, all 13 seconds at f/2.5 with the 35mm lens and Canon 6D MkII at ISO 6400. Topaz DeNoise AI applied.

What Exposures Do I Use?

There is no single best setting. It depends on …

— How bright the sky is from your location (urban vs a rural site).

— Whether the Moon is up — it will be after July 23 or so when the Moon returns to the western sky as a waxing crescent.

— The phase of the Moon — in late July it will be waxing to Full on August 3 when the sky will be very bright and the comet faint enough it might lost in the bright sky.

However, here are guidelines:

— ISO 400 to 1600

— Aperture f/2 to f/4

— Shutter speed of 4 to 30 seconds

Unless you are shooting in a very bright sky, your automatic exposure settings are likely not going to work.

As with almost all nightscape photography you will need to set your camera on Manual (M) and dial in those settings for ISO, Aperture and Shutter Speed manually. Just how is something you need to consult your camera’s instruction manual for, as some point-and-shoot snapshot cameras are simply not designed to be used manually.

Panorama of Comet NEOWISE Over Prince of Wales Hotel (July 14, 2
A once-in-a-lifetime scene — A panorama of the dawn sky at 4 am on July 14, 2020 from Waterton Lakes National Park, Alberta, Canada with Comet NEOWISE (C/2020 F3) over the iconic Prince of Wales Hotel. Noctilucent clouds glow below the comet in the dawn twilight. Venus is rising right of centre paired with Aldebaran and the Hyades star cluster, while the Pleiades cluster shine above. The waning quarter Moon shines above the Vimy Peak at far right. The Big Dipper is partly visible above the mountain at far left. Capella and the stars of Auriga are at centre. This is an 8-segment panorama with the 35mm Canon lens at f/2.5 for 15 seconds each at ISO 100 with the Canon 6D MkII and stitched with Adobe Camera Raw.

Exposure Considerations 

As a rule you want to …

— Keep the ISO as low as possible for the lowest noise. The higher the ISO the worse the noise. But … do raise the ISO high enough to get a well-exposed image. Better to shoot at ISO 3200 and expose well, than at ISO 800 and end up with a dark, underexposed image.

— Shoot at a wide aperture, such as f/2 or f/2.8. The wider the aperture (smaller the f-number) the shorter the exposure can be and/or lower the ISO can be. But … lens aberrations might spoil the sharpness of the image. 

— Keep exposures short enough that the stars won’t trail too much during the exposure due to Earth’s rotation. The “500 Rule” of thumb says exposures should be no longer than 500 / Focal length of your lens. 

So for a 50mm lens exposures should be no longer than 500/50 = 10s seconds. You’ll still see some trailing but not enough to spoil the image. And going a bit longer in exposure time can make it possible to use a slower and less noisy ISO speed or simply having a better exposed shot. 

Histogram
The histogram as shown in Adobe Camera Raw. Cameras also display the image’s histogram in the Live View preview and in playback of recorded images. Keep the histogram from slamming to the left.

— Avoid underexposing. If you can, call up the “histogram”— the graph of exposure values — on the resulting image in playback on your camera. The histogram should look fairly well distributed from left to right and not all bunched up at the left. 

Comet NEOWISE Over Dinosaur Park (July 15, 2020)
This is Comet NEOWISE (C/2020 F3) over the badlands and formations of Dinosaur Provincial Park, Alberta, on the night of July 14-15, 202. This is a blend of 6 exposures for the ground stacked to smooth noise, with a single exposure for the sky, with the 35mm Canon lens and Canon 6D MkII. The ground exposures are 1- and 2-minutes at ISO 1600 and f/2.8, while the single untracked sky exposure was 20 seconds at ISO 3200 and f/2.5.

My Nightscapes and Time-Lapses ebook shown above provides extensive instruction on the best camera settings for exposure and noise reduction.

Location Considerations

When and where you are will also affect your exposure combination. 

If you are at a site with lots of lights such as overlooking a city skyline, exposures will need to be shorter than at a dark site. 

And nights with a bright Moon will require shorter exposures than moonless nights.

Take test shots and see what looks good! Inspect the histogram. This isn’t like shooting with film when we had no idea if we got the shot until it was too late! 


What Lens Do I Use?

Comet over Canola Field (July 15, 2020)
With a 35mm lens. Comet NEOWISE (C/2020 F3) over a ripening canola field near home in southern Alberta, on the night of July 15-16, 2020. This is a blend of a stack of six 2-minute exposures at ISO 3200 and f/5.6 to smooth noise, provide depth of field, and bring out the colours of the canola, blended with a single short 15-second exposure of the sky at f/2.8 and ISO 1600, all with the 35mm lens and Canon 6D MkII camera.
Comet over Canola Field Close-Up (July 15, 2020)
With a 50mm lens. Comet NEOWISE (C/2020 F3) over a ripening canola field near home in southern Alberta, on the night of July 15-16, 2020. This is a blend of a stack of three 2-minute exposures at ISO 1600 and f/5 to smooth noise, provide depth of field, and bring out the colours of the canola, blended with a single short 15-second exposure of the sky at f/2.8 and ISO 3200, all with the 50mm Sigma lens and Canon 6D MkII camera.

Any lens can produce a fine shot. Choose the lens to frame the scene well. 

Using a longer lens (105mm to 200mm) does make the comet larger, but … might make it more difficult to also frame it above a landscape. A good choice is likely a 24mm to 85mm lens.

A fast lens is best, to keep exposure times below the 500 Rule threshold and ISO speeds lower. Slow f/5.6 kit zooms can be used but do pose challenges for getting well exposed and untrailed shots. 

Shooting with shorter focal lengths can help keep the aperture wider and faster. Long focal lengths aren’t needed, especially for images of the comet over a landscape. Avoid the temptation to use that monster 400mm or 600mm telephoto wildlife lens. Unless it is on a tracker (see below) it will produce a trailed mess. It is best to shoot with no more than a 135mm telephoto, the faster the better, IF you want a close-up.

Planetarium programs that I recommend below offer “field of view” indicators so you can preview how much of the horizon and sky your camera and lens combination will show. 

StarryNightFOV
StarryNight™ and other programs offer “Field of View” indicator frames that can show how the scene will frame with (in this example) lenses from 24mm to 135mm.

Can I Use My [insert camera here] Camera?

Yes. Whatever you have, try it. 

However, the best cameras for any nightscape photography are DSLRs and Mirrorless cameras, either full-frame or cropped frame. They have the lowest noise and are easiest to set manually. 

In my experience in teaching workshops I find that the insidious menus of automatic “point-and-shoot” pocket cameras make it very difficult to find the manual settings. And some have such noisy sensors they do not allow longer exposures and/or higher ISO speeds. But try their Night or Fireworks scene modes. 

It doesn’t hurt to try, but if you don’t get the shot, don’t fuss. Just enjoy the view with your eyes and binoculars. 

But … if you have an iPhone11 or recent Android phone (I have neither!) their “Night scene” modes are superb and use clever in-camera image stacking and processing routines to yield surprisingly good images. Give them a try — keep the camera steady and shoot. 

Comet NEOWISE with NLCs Above Prairie Lake (July 10-11, 2020)
This is Comet NEOWISE (C/2020 F3) over Deadhorse Lake near Hussar in southern Alberta, taken just after midnight on July 10-11, 2020 during its evening appearance. The comet shines just above low noctilucent clouds. This is a blend of nine exposures for the ground stacked to smooth noise and the water, with a single exposure for the sky, all 4 seconds with the 135mm Canon lens at f/2 and Canon 6D MkII at ISO 1600.

What No One Asks: How Do I Focus?

Everyone fusses about “the best” exposure. 

What no one thinks of is how they will focus at night. What ruins images is often not bad exposure (a lot of exposure sins can be fixed in processing) but poor focus (which cannot be fixed later).

On bright scenes it is possible your camera’s Autofocus system will “see” enough in the scene to work and focus the lens. Great.

On dark scenes it will not. You must manually focus. Do that using your camera’s “Live View” function (all DSLRs and Mirrorless cameras have it — but check your user manual as on DSLRs it might need to be activated in the menus if you have never used it). 

Canon 6D Live View Wide
The Live View screen of a Canon DSLR. Look in your manual for tips on how to boost the Live screen image brightness with the Exposure Simulation option.
Canon 6D Live View Zoom5x
Magnify the image 5x, 10x or more with the Zoom box centred on a star to focus the star to a pinpoint.

Aim at a bright star or distant light and magnify the image 5x or 10x (with the + button) to inspect the star or light. Put the lens on MF (not AF) and focus the lens manually to make the star as pinpoint as possible. Do not touch the lens afterwards. 

Practice on a cloudy night on distant lights.

All shooting must be done with a camera on a good tripod. As such, turn OFF any image stabilization (IS), whether it be on the lens or in the camera. IS can ruin shots taken on a tripod. 


What Few Ask: How Do I Plan a Shoot? 

Good photos rarely happen by accident. They require planning. That’s part of the challenge and satisfaction of getting the once-in-a-lifetime shot. 

To get the shot of the comet over some striking scene below, you have to figure out:

— First, where the comet will be in the sky, 

— Then, where you need to be to look toward that location. 

— And of course, you need to be where the sky will be clear!

Stellarium Web
The free web version of Stellarium shows the comet, as do the paid mobile apps.
  1. Planning Where the Comet Will Be 

Popular planning software such as PhotoPills and The Photographer’s Ephemeris can help immensely, but won’t have the comet itself included in their displays, just the position of the Sun, Moon and Milky Way.

For previewing the comet’s position in the sky, I use the planetarium programs Starry Night (desktop) or SkySafari (mobile app). Both include comet positions. 

The program Stellarium (stellarium.org) is free for desktop while the mobile Stellarium Plus apps (iOS and Android) have a small fee. There is also a free web-based version at https://stellarium-web.org  Be sure to allow it to access your location. 

Set the programs to the night in question to see where the comet will be in relation to the stars and patterns such as the Big Dipper. Note the comet’s altitude in degrees and azimuth (how far along the horizon it will be). For example, an azimuth of 320° puts it in the northwest (270° is due west; 0° or 360° is due north, 315° is directly northwest). 

Comet NEOWISE and NLCs over Prince of Wales Hotel (July 14, 2020
Comet NEOWISE (C/2020 F3) with a small display of noctilucent clouds over Emerald Bay and the iconic Prince of Wales Hotel at Waterton Lakes National Park, Alberta, at dawn on July 14, 2020. This is a blend of a stack of four exposures for the ground and water to smooth noise, blended with a single short exposure for the sky, all 20 seconds at f/2.5 and ISO 400. All with the 35mm Canon lens and Canon 6D MkII camera.
  1. Planning Where You Need To Be

I use The Photographer’s Ephemeris mobile app (https://www.photoephemeris.com) — there is a free web version available. Many like PhotoPills (https://www.photopills.com).

With either you can dial in the time and date and see lines pointing toward where the Sun would be, but below the horizon. Scrub through time to move that line to the same azimuth angle as where the comet will be and then see if the comet is sitting in the right direction. 

TPE
The screen from The Photographer’s Ephemeris app showing the planning map for the image above, with the faint yellow line indicating the line toward the comet’s azimuth.

Move your location to place the line toward the comet over what you want to include in the scene.

TPE 3D
The simulation of the real scene above, of the comet over the Prince of Wales Hotel, using TPE 3D app. The simulation matches the real scene very well!

I like The Photographer’s Ephemeris as it links to the companion app TPE3D that can show the stars over the actual topographic landscape. It won’t show the comet, but if you know where it is in the sky you can see if if will clear mountains, for example.

Astrospheric
The Astrospheric app prediction of skies for me for the night I prepared this blog. Not great! But clear skies could be found to to east with a fresh hours drive.
  1. Planning for the Weather 

All is for nought if the sky is cloudy. 

For planning astro shoots I like the app Astrospheric (https://www.astrospheric.com). It is free for mobile and there is a web-based version. It uses Environment Canada predictions of cloud cover for North America. Use it to plan where to be for clear skies first, then figure out the best scenic site that will be under those clear skies. 

For sites outside North America, try ClearOutside (https://clearoutside.com) 


Advanced Techniques 

Be happy to get a well-composed and exposed single shot. 

But … if you wish to try some more advanced techniques for later processing, here are suggestions.

Comet NEOWISE and Aurora Panorama (July 13, 2020)
A panorama of the sky just before midnight on July 13, 2020 from Waterton Lakes National Park, Alberta, Canada with Comet NEOWISE (C/2020 F3) over the front range of the Rocky Mountains and an arc of aurora across the north. This is a 6-segment panorama with the 35mm Canon lens at f/2.2 for 25 seconds each at ISO 800 with the Canon 6D MkII and stitched with Adobe Camera Raw.

1. Panoramas

On several nights I’ve found a panorama captures the scene better, including the comet in context with the wide horizon, sweep of the twilight arch or, as we’ve had in western Canada, some Northern Lights.

Take several identical exposures, moving the camera 10 to 15 degrees between images. Editing programs such as Lightroom, Adobe Camera Raw, ON1 Photo RAW and Affinity Photo have panorama stitching routines built in. 

My Nightscapes and Time-Lapses ebook shown above provides tutorials for shooting and processing nightscape panoramas. 

Comet NEOWISE over Red Deer River Panorama (July 11, 2020)
What a magical scene this was! This is Comet NEOWISE (C/2020 F3) over the sweep of the Red Deer River and Badlands from Orkney Viewpoint north of Drumheller, Alberta, on the morning of July 11, 2020. Light from the waning gibbous Moon provides the illumination, plus twilight. This nicely shows the arch of the twilight colours. This is a 6-segment panorama with the 50mm Sigma lens at f/2.8 and Canon 6D MkII at ISO 400 for 13 seconds each. Stitched with Adobe Camera Raw. Topaz DeNoise AI and Sharpen AI applied.

2. Exposure Blending 

If you have a situation where the sky is bright but the ground is dark, or vice versa, and one exposure cannot record both well, then shoot two exposures, each best suited to recording the sky and ground individually. 

For example, on moonless nights I’ve been shooting 2- to 5-minute long exposures for the ground and with the lens stopped down to f/5.6 or f/8 for better depth of field to be sure the foreground was in focus. 

For a video tutorial on how to do the layering and masking in programs such as Photoshop, see my How to Shoot Moonlit Nightscapes video at https://vimeo.com/theamazingsky/moonlighttutorial. 

Comet NEOWISE over Horseshoe Canyon (July 11, 2020)
This is Comet NEOWISE (C/2020 F3) over the Horseshoe Canyon formation near Drumheller, Alberta on the night of July 10-11, 2020, taken about 2 a.m. MDT with the comet just past lower culmination with it circumpolar at this time. Warm light from the rising waning gibbous Moon provides the illumination. This is a blend of six 1- and 2-minute exposures for the ground at ISO 800 and 400 stacked to smooth noise, with a single 30-second exposure at ISO 1600 for the sky, all with the 35mm Canon lens at f/2.8 and Canon 6D MkII.

3. Exposure Stacking 

To reduce noise, it is also possible to shoot multiple exposures to stack later in processing to smooth noise. This is most useful in scenes with dark foregrounds where noise is most obvious, and where I will stack 4 to 8 images. 

Just how to do this is beyond the scope of this blog. I also give step-by-step tutorials for the process in my Nightscapes and Time-Lapses ebook shown above. It be done in Photoshop, or in specialized programs such as StarryLandscapeStacker (for MacOS) or Sequator (Windows). 

But shoot the images now, and learn later how to use them. 

Comet NEOWISE Close-Up (July 15, 2020)
A close-up of Comet NEOWISE (C/2020 F3) on the night of July 14/15, 2020 with a 135mm telephoto lens. This is a stack of nine 1-minute exposures with the 135mm Canon lens wide-open at f/2 and Canon EOS Ra camera at ISO 800. The camera was on the iOptron SkyGuider Pro tracker tracking the stars not the comet. Stacked and aligned in Photoshop.

4. Tracking the Sky 

If it is close-ups of the comet you want, then you will need to use a 135mm to 300mm telephoto lens (especially later in the summer when the comet is farther away and smaller). 

But with such lenses any exposure over a few seconds will result in lots of trailing. 

iOptron SkyGuider Pro
The iOptron SkyGuider Pro and 135mm lens used to take the close-up shot of the comet above.

The solution is a tracking device such as the Sky-Watcher Star Adventurer or iOptron SkyGuider. These need to be set up so their rotation axis aims at the North Celestial Pole near Polaris. The camera can then follow the stars for the required exposures of up to a minute or more needed to record the comet and its tails well. 

Star Adventurer Polar Axis Angle
This is the Sky-Watcher Star Adventurer. All trackers have a polar axis that needs to be aligned to the Celestial Pole, near Polaris.

Just how to use a tracker is again beyond the scope of this blog. But if you have one, it will work very well for comet shots with telephoto lenses. However, trackers are not essential for wide-angle shots, especially once the Moon begins to light the sky.

But later in the summer when the comet is fainter and smaller, a tracked and stacked set of telephoto lens images will likely be the best way to capture the comet.

Clear skies and happy comet hunting!

— Alan, July 18, 2020 /Revised July 23 / AmazingSky.com 

 

7 Replies to “How to Photograph Comet NEOWISE”

    1. No one knows when the next bright comet will appear as it will very likely be one that hasn’t been seen for thousands of years so isn’t in the catalog.

  1. This is great tutorial for me – a beginner. Any chance you could have option to download a PDF of emails such as these so we can save and reference?

  2. Alan— This is one of the most comprehensive “How Tos” on photographing Comet NEOWISE which I have run across. What I am most interested in is your technique for stacking and blending images of the comet. Is that technique covered in your Apple ebook? If I download your ebook can I use it on either one of my two Apple computers?

    I tried stacking using Starry Landscape Stacker (SLS) and received the message from SLS that my multiple images could not be stacked because I was shooting with a 200mm lens and the images were not tracked. Any way to get around that short of buying a tracker?

    Thanks.

    Hadley Johnson Davis, CA

    >

    1. The ebook doesn’t cover comets per se but in none of my shots have I tried to stack and register the stars separate from the moving comet. That takes DeepSkyStacker or PixInsight I think. I’m not sure what you are trying to do – stack 200mm untracked shots that also have a landscape foreground? That would be best done with a tracker for the sky and then turning it off for the ground shots. Shooting with that long a focal length really needs a tracker. Then the images are easy to stack and align. Photoshop will do it.

  3. Great tips! Thanks so much. I got some pics last night, but will use your tips and make them even better.

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