Shooting the Aurora

The Northern Lights over Alaska Grizzly Lodge outside Fairbanks.

The Northern Lights over Alaska Grizzly Lodge outside Fairbanks.

This spring I had the opportunity to take a family vacation to Alaska where my youngest son is attending college. We stayed in and toured the areas around both Anchorage and Fairbanks – which was a good 8+ hour drive north, and just shouting distance from the Arctic Circle. A mishap with my Canon 5D Mark III just days before we left meant I had to “settle” for a rented 6D from BorrowLenses.com while my star quarterback was in for repairs. I did get to do quite a bit of vacation photography of course, but my deepest desire was to catch the Aurora. Before the trip, I even purchased (getting tired of renting the same focal length over and over again) a Rokinon 14mm f/2.8 prime lens (more on this later) with the hope of clear cold skies for some nightscape shots.

Fairbanks Alaska is an excellent, and somewhat underrated Aurora destination. In the winter time when the days are short Fairbanks is not as glamorous as Iceland or northern Europe, but it is vastly more affordable and accessible for North Americans. Be advised too that Fairbanks is a sleepy little town in the Winter; in fact a good portion of Alaska’s tourism trade is simply boarded up for the Winter, so you need to be self sufficient and not bring along family members that need to be constantly “entertained”. It is however for the quiet soul, a supremely beautiful and tranquil place to spend a week in the deep Winter time. There will be snow, cold, and icy roads… rent a car with four wheel drive and good tires and you’ll be set! We stayed at the very rustic and authentic Alaska Grizzly Lodge, which is just north of Fairbanks proper. On my first visit to Alaska I discovered this lodge by accident on a summer camping trip when my two sons and I emerged from the wild bedraggled and in much need of a clean bed and a shower. Anita Tomsha, the proprietor told me about how busy she was in the Winter time with Japanese tourists coming over to see the Aurora and I made a mental note that I made good on this next trip to Alaska.

What You Need

We are not in Florida anymore Toto...

We are not in Florida anymore Toto…

Warm clothes. Really, I can’t stress enough how cold it is there. You need a hat, one that covers your ears, preferably a hooded coat and gloves. Get some hand warmers, we are talking serious pain when your fingers and hand are out fiddling with your camera’s tiny buttons in the cold. Just putting them back in your pocket doesn’t work… the cloth pockets feel like your sticking your hand in a paper or cardboard envelope lined with sand paper, and it’s no relief. Those chemical hand warmers are a gift from God whether you believe in him or not! Lots of layers. My only regret was not having a face covering as my cheeks and nose were stinging in the cold within minutes of stepping outside. Hot chocolate or coffee are great, but won’t last a minute outdoors, drink up during your warm up breaks. When possible, breathe through your nose, don’t gulp air quickly with your mouth. In other words, walk don’t run class when your out in the bitter cold. DO NOT BREATH ON YOUR CAMERA! Unless you like playing jack frost… and of course toasting any chance of getting a picture through a frosted lens.

Camera accessory wise, you need a tripod, a wide fast lens, and a spare battery or two. A spacious memory card won’t hurt either. You should also bring along a large plastic bag and some desiccant. You will only be able to stay outside for a while and eventually you’ll have to go back in to warm up. If not you, your camera will simply quit working when it get’s this cold. Put the camera in the bag with the desiccant (available at most camera stores) and squeeze all the air out of it before heading inside. It’s winter and it’s dry, but your camera and other equipment will not just dew up when you bring it inside, it will frost over like a beer mug. If you don’t take some precautions, the same thing is happening to the electronics and optical surfaces inside the camera. Let your camera warm up before you try and dump the photographs to your laptop too. If your taking multiple trips, remove it from the bag only when your back outside.

Best Practices

Well, this is my formula anyway and it seemed to work pretty well. Your milage may vary. Instead of an intervalometer, I set my camera for a 10 second delayed timer. Press the button, and ten seconds later, the shutter opens. This provides enough time for the camera/tripod shake to dampen before taking the image, and it’s one less thing to keep track of in the cold and dark. I also turn on mirror lock so the actual shutter opens 10 seconds after the mirror flips up. I know some people claim this does no good on long exposures, but I can’t see this as the case. If it’s bad to shake your camera at anytime during an exposure, it’s bad to shake it at the beginning, and there is always “something” in your frame that is bright and it will not be as sharp. Once you start stretching things, those little faint blurs start to come out more as well, I always use mirror lock for nightscape photography.

Autofocus does not work on star fields, so you have to focus manually. I wore my reading glasses and used live view on the back LCD to focus the lens by hand. I pointed the camera towards a bright star that would show up in live view, and then zoomed in on it with the LCD controls to a 1x view. Tweak your focus ring until the star is as small and tight as you can make it and then your done. Don’t touch the focus ring again, and you don’t need to refocus when you move around. The actual best focus position will likely be near, but not exactly on the infinity symbol. In fact, I’ve never seen it exactly ON the infinity symbol. I wasn’t as familiar with the controls on the 6D as on my 5D and they were just different enough to require some practice and rehearsal indoors. Out in the dark, you need to know what the third button from the bottom on the left does without having to reach for a flashlight.

Sky Glow is harder to control in my opinion.

Sky Glow is harder to control in my opinion.

I shot manual of course, at ISO 3200 for 10 seconds. No high ISO noise reduction, but I did let the camera do a “long exposure noise reduction”, which simply shoots and subtracts a dark frame after each image. This get’s rid of hot pixels and some thermal noise, even though it was quite cold, the chip does get warm when in use. You will need to experiment with your own camera to see if this get’s enough detail for you. My first set of shots were at 20 seconds and they were too long as they picked up a great deal of sky glow. I got far better results in post processing stretching up, rather than suppressing the surrounding glow. This is exactly the opposite I know of accepted wisdom for controlling noise in daytime shots and perhaps you know some tricks that I don’t for post processing, but my experience with deep sky astrophotography made me more comfortable stretching up rather than trying to suppress sky glow. A few more aurora trips and some more practice I might change my mind… but I was happy with my end product which is what counts. Adobe Camera Raw has excellent noise reduction filters too. Note in the image shown here, there is a hint of green and red from an oncoming outburst. White balance is irrelevant when your shooting raw by the way.

Raw out of the camera with  a shorter exposure.

Raw out of the camera with a shorter exposure.

I shot with my new Rokinon lens wide open at f/2.8. I was actually quite dissatisfied with this lens at any aperture. There was a great deal of asymmetry, sharp stars in the middle, round out of focus stars to the right, and elongated streaks of stars to the left and upper left. At the scale presented here, this is okay, but for the discerning photographer this will just not do. I’ve heard from friends that these lenses are hit or miss for the money, and I’m exchanging the one I had for another to give them one more try. You can see in this raw image that 10 seconds was more than enough time to get some bright features showing up. The aurora are moving too, although not as quickly as you see in some animations, but certainly fast enough that they are always a bit blurred. The shorter you can expose and still get good signal, the better! Shooting wide open with the best lens will give you some distorted stars, but the overall effect is quite acceptable for the wide field presentation, and the wider aperture allows for shorter sharper exposures of a not terribly bright moving subject. Speaking of moving subjects, since your shooting short exposures at very short focal lengths, the movement of the stars has little effect on the star field. A camera sky tracker would be counterproductive, as recall the aurora are a moving target and you want your exposures to be as short as you can get away with.

Video did not work at all, there’s just not enough light. In hindsight, an intervalometer might have been a good idea as my only regret is that I didn’t do any time lapse sequences. Ah, well next time!

A final tweaked rendition.

A final tweaked rendition.

Once you have your raw files, it’s pretty much sweeten to taste. I applied a lens correction to fix some barrel distortion these lenses are known for, and to repair some of the vignetting. I also cropped it down a bit and then you enter the phase of tweaking shadows and highlights and color balance to get what you like. One of the most surprising aspects of the aurora shots was the presence of a considerable amount of magenta or reddish hues. I suppressed it a little to get the cold feel I wanted, but left enough in to be faithful to what was visible.

Luck of the Irish?

Anita told me, “you can’t just show up any old time and shoot aurora when it get’s dark” (paraphrased). Many people go on aurora trips and are disappointed when there is no outbreak. You simply can’t predict months in advance exactly when a solar flare will erupt, and strike the earth, but at least in the dark winter months of the north, your chances are better than in summer time when there may only be an hour or less of darkness. On my first night, I shot some test exposures and gave up and came inside to keep warm when nothing but a faint glow showed up on the camera. However, an hour later a fellow photographer (the lodge was full of happy aspiring aurora photographers) came in and he was getting a bright green streak! Alert – alert – all hands on deck – this is not a drill! Aurora outburst can come along at any time, and they can last only a few minutes or a few hours. In my case, we lucked out and had two nights with about two hours of good activity to watch and photograph… and really, at least once you owe it to yourself to stop shooting and just stand there and watch them dance. I can see why our ancestors thought it was the work of the gods as I stood there in awe with an Enya sound track playing in my head.

Where are the Aurora now?

Where are the Aurora now?

There’s a web site too that is great for keeping an eye on the aurora and on a given evening you can predict to within an hour or so when they are going to hit. I returned home from Alaska the day before the great aurora outbreak on Saint Patricks Day 2015. I received a few teasing texts from friends about coming home too soon and missing the “big one”. I don’t feel cheated though. I’ve made many an imaging trip with far more equipment only to end up with nothing due to weather. This time the weather was in my favor and I had two good nights of Aurora, my first time ever not to mention. I was happy when I left with my catch, I’m certainly not going to be unhappy now because chances were just as good or better than I’d return with nothing but star trails and glacier pictures. Well, actually I was pretty happy with the glacier stuff too, but that’s not what this blog is about 🙂

Richard

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