How to Photograph the Aurora Borealis – Eight Essential Steps – Alaska Photography Tours, Private Guiding & Classes

by Carl Johnson, Owner Alaska Photo Treks

When I first moved to Alaska, my idea of chasing the northern lights was to go out on any clear night in the winter and wait for the northern lights to dance. I quickly found out how incredibly wrong I was. The more I spent time chasing, the more I came to understand how to do it successfully. Here is what I have learned over the years that leads to a successful aurora hunt.

1. Know the Conditions

Unless you live above the Arctic Circle, you just cannot go out on any clear, dark night and see the aurora. There are specific conditions that affect aurora viewing, narrowed down to three specific factors: sun activity, phase of the moon, and cloud cover.

Solar Activity. Most people look simply to the Kp forecast to determine when to go out. In more northern climates, like Alaska, the Kp means nothing. “Kp” is short for the Planetary K-Index. It is a three-hour average of ground based magnetometers around the world. The scale, measured from 0-9, indicates how far south the aurora might be visible. But a high Kp index does not mean the aurora will be visible. The single most influential factor in aurora visibility and activity is the sun’s magnetic charge carried in the solar winds, known as the Interplanetary Magnetic Field. We look for two particular factors of the IMF – the magnetic polarity (measured in units called Bz) and the strength of the magnetic field (measured in B total or Bt). Since the Earth’s magnetic field is a constant positive, we need an IMF Bz in the negative numbers to produce more active, visible aurora displays. The lower the number, the better. More active results start around a -7 Bz. For the Bt, we prefer numbers higher than six. A strong, positive Bz (like a +20), will shut down the aurora.

Moon Phase. The moon will affect aurora viewing. The brighter the moon, the more it acts like light pollution. From data we have collected over the years, we have split up the moon phase into three areas. Moon illumination below 40% will not affect viewing a quiet aurora display. From 40-75%, it might affect viewing a quiet aurora, but not completely prevent it. Any moon illumination over 75% will completely block viewing a quiet aurora display. But active displays are still visible, even under 100% moon illumination. For good landscape photography, a moon illumination of around 40% is ideal, to allow your camera to capture details in the landscape.

Cloud Cover. Lastly, cloud cover will affect aurora viewing. Clear skies or mostly clear skies (10-30% cloud coverage) will not affect aurora viewing. In fact, sometimes clouds add interesting elements to aurora photos. But the cloudier it gets, the more aurora viewing may be affected. Certain types of clouds, like high altitude clouds, may still allow for aurora viewing. Generally speaking, if you can see the stars, you can see the aurora. A complicating factor is the moon. As it gets brighter, it also lights up those clouds like a soft box for a portrait studio strobe.

2. Be Ready for the Road

Unless you know how to drive in winter conditions, you really should let someone else do that part. (Book a tour!) If you do, it still pays to be prepared. Always travel with a roadside emergency kit, water, and food. I take food, hot water, instant drinks (like coffee and hot chocolate) and a -20F rated sleeping bag. I also load a pair of snowshoes and poles in case the snow is too deep and I really want to get out in the snow.

Be dressed for cold conditions. When I am driving, I am wearing fewer layers and basic shoes. But when gearing up for being outside, I go to specific gear to be ready for extended periods away from the warmth of my car. From head to toe, you will not see me wearing cotton. It has to be either synthetic or wool or fur, for the simple reason that cotton, when wet, takes longer to dry and does not retain heat as well. My head is covered with wool or fur. I wear a down parka, with two layers on underneath. For pants, I will wear insulated pants. For my hands, I use the Heat 3 Smart Gloves by the Heat Company. On my feet, a pair of wool socks and a set of Cabela’s Trans-Alaska boots.

3. Check Real Time Data

There are forecasts, and there is the NOW, the current conditions. Both are necessary to plan and be ready for the right night to chase the aurora. Many people will rely on the 27-day outlook, but it is merely predictive modeling based on the previous month’s solar activity. The best forecast to utilize is the three-day forecast, as it is based on observed, detected conditions in the sun. If you have not done so already, you can subscribe from the NOAA Space Weather Prediction Center for free for a three-day forecast that shows up in your email inbox and is updated three times daily. Go to the footer on the home page, right side and click on “SUBSCRIBE.” Under “Forecasts and Summaries,” select the NOAA 3-Day Forecast. You can also sign up on the same page for email alerts when the aurora is reaching certain Kp levels.

But on the night you are out, you want to be checking the real time data. There is a network of satellites orbiting the Earth, and they detect the incoming solar wind stream. Once that stream hits the satellites, it takes about an hour for the charged particles of the solar winds to strike the atmosphere. When in the field, we rely on the Amazing Aurora mobile app (see below). That provides up to a one-hour notice of incoming solar wind data (Interplanetary Magnetic filed Bz and Bt, solar wind density and speed, and hemispheric power (HPI) – learn what each means).

4. Know where to Go

Generally, speaking, you will want to head away from light pollution. Aurora chasing is an odds game, and you want to increase your odds by limiting what interferes with viewing it. While it is possible to see the northern lights in the heart of a city (see below), that will only be during a bright, active aurora display. Heading to a darker area allows you to see the aurora even when it is quiet. Related to that, be observant of how your own light affects your photography. While white lights from a headlamp or headlights are obviously bright, you will be surprised how much the dim red light of a headlamp will affect the scene.

Additionally, you need to select a location where the horizon is low. You do not want to try to start viewing the aurora where there are tall mountains right next to you. You need an unobstructed view to the north-northeast, and a low horizon helps you to see the aurora borealis much better. When the aurora first starts in the night sky, it is most often a low arc on the horizon. If that low arc is behind a wall of mountains, you will not see it. Knowing where the best location is to start will involve some scouting at your location, or planning ahead using tools like Google Earth.

5. Protect Your Gear

A long night of cold conditions will affect several aspects of your photography gear, so be prepared for that. There are three main factors to consider.

Lens condensation. One of the main challenges is moisture build-up on the face of the lens. This will produce hazy, diffuse photos when frost starts to build on the lens elements. You can mitigate this in several ways. First, be careful of how you exhale – you don’t want to add moisture to your lens. In many locations, there will be plenty of moisture in the air already. Second, periodically check the face of your lens for frost build up, and have a lens rag ready to clean it off. Third, cover your camera and lens with a cloth when you are not using it to protect it. And last, never bring your camera and lens into a warm environment after it has been out in the cold for a while. This will create instant condensation on and inside your lens as well as your camera. You an avoid this by placing your camera (with lens attached) fully inside your camera bag and sealing it up before you bring it inside to a warm environment.

Battery life. Camera batteries do not like the cold. Over time, cold temperatures will drain them, and the colder the temp, the faster the drain. Always take at least two spare batteries with you into the field (for the Sony a7s series camera, bring more), and keep them in a place where they will stay warm. I like to keep them in an inside pocket against my body heat. As battery power gets low in your camera, swap out the cold, drained batter with a warm, fully-charged one. Then put the cold battery in a place where it can warm up a bit – you will see it recover its charge a bit.

Tripod. Tripod joints and ballheads tend to get stiff as they are exposed to cold for a long time. To protect tripod joints in cold temperatures, ensure they are well-lubricated with a product designed specifically for ballheads. Additionally, tripod legs get cold, even carbon-fiber legs. No matter how good your gloves are, that cold can seep through over time. There are a variety of tripod leg covers available from black to multiple hues of camouflage, or you can get the right size of pipe insulation foam from a nearby Lowes, cut the foam to the right length, slit it to go over your legs, and seal them up with duct tape. It just depends on the look you are going for.

6. Taking the Photos

With modern smart phones, it is possible to take decent photos of the aurora borealis. Most manufacturers have a “night mode” that allows you to take longer exposures. The typical default exposure time is three seconds. You will want to research how to override that and extend the night mode exposure time for your model of phone. Consider adding apps that allow you to manually expose with more controls. Current options include Camera+ app (iPhone), the Filmic Pro or Camera FV-5 Lite app (Samsung), or Firstlight or Filmic Pro app (Google).

Fort those with digital cameras like a DSLR or mirrorless camera, you will want a combination of lenses from 14-70mm, preferably with an aperture as wide as f/2.8. You will want to start with these settings:

Manual exposure mode. Switch to the “M” on the exposure dial and set all three components of the “Exposure Triangle” yourself. Auto exposure does not work in the dark. And unless the moon is bright, neither does Aperture Priority.

Aperture set wide open. For the highest quality zoom lenses, this will be f/2.8. Prime lenses can go as wide as f1/4, which is two stops wider than f2/8. Many consumer-grade lenses only go as wide as f/4.0, which means you will have to increase either your ISO or shutter speed settings below.

ISO at 1600. This is just a starting point under typical conditions. If the moon is bright, you may start lower (at 800 or even 400). If conditions are really dark and the aurora is quiet, you may start at 3200. As the aurora gets brighter and faster, you may want to adjust this higher to 3200 or even 6400. The faster the aurora moves, the faster shutter speed you will want (see next). In that case, a higher ISO is warranted. Modern denoise software, either Topaz or the Adobe Lightroom built-in Denoise AI, make concerns over higher ISO pretty much a thing of the past.

Shutter speed at 15 seconds. Like with ISO, this is just a starting point. If the aurora is really quiet, you may want to set a longer exposure. Depending on what focal length you are shooting at (14mm versus 24mm), at some point you start to get star trail movement if you go too long. As the aurora gets brighter, you can start to shorten your exposure times. At some point, the aurora will start to move, and then move very quickly. When that happens, like with a corona display (see below), you will want the shortest exposure time you can get in order to preserve the detail in the formation. Longer shutter speeds will blur these details, like with a smooth waterfall photo.

White balance at Auto. For most camera models, this will give the most accurate color rendering for night sky photography.

Shoot in RAW format. The RAW format is the digital equivalent of a slide or negative – it preserves the most data. It will give you the most leeway in processing the digital file, and make it easier to adjust white balance if the Auto white balance did not produce the desired color.

Manual focus at Infinity. This is the greatest challenge for the night sky photographer – focus. For many consumer-grade lenses, this can be frustrating. Many such lenses either do not have an infinity symbol or the focus ring never stops at infinity – it just keeps rotating. The key is to figure out your lens, pick a starting point, and take a photo. Zoom in digitally on the image to see if the stars or any solid lines (mountain ridge, tree) are sharp. If they are not, rotate your focus ring slightly, and try again. If the sharpness improves, keep adjusting. Once you have obtained focus, lock down the focus ring with a strip of gaffers tape. When you move to a new location, check focus again. The focus ring can sometimes move during transit.

Shutter Release. You are using a tripod in order to stabilize and have sharp photos, but the act of touching the shutter button on your camera can also cause minor camera motion during the longer exposure. To avoid that, use a cable or remote trigger to release your shutter. If none is available, use your self-timer, but set it to 2 seconds. Most cameras default to ten seconds, and that can feel like forever when the aurora is taking off.

Image Stabilization. Whether on your lens or camera, make sure to turn off your image stabilization. During a long exposure, this feature will try to “stabilize” the image, and in doing so, cause camera motion and ruin your shot.

Filters. Lastly, remove any filters from the front of your lens, even a protective UV filter. This was cause an effect called Newton’s Rings, which is a set of concentric circles in the middle of your photo in the same color as the aurora. It is caused by the light of the aurora bouncing back and forth between the concave elements of the lens and the flat element of the filter.

7. Think about Composition

It is easy to get excited when the aurora is really going off. You end up chasing squirrels, moving around and shooting the aurora wherever it is and whatever it is doing. Remember that aurora borealis photography is still landscape photography. When the aurora is quiet, or not even visible yet, become familiar with your surroundings. (This may also be part of your daytime scouting trip to the location.) Think about what kind of composition you would like to have with the aurora borealis when it comes out. This is why locations you choose to visit also matter. What sort of terrain is it – rolling hills and trees or mountains? Is there open water at that time of year? These are elements that will help to make more interesting photos. And remember to always vary your composition between horizontal and vertical.

8. Give Yourself Time

Aurora chasing is a marathon, not a sprint. Make sure you are out late enough and long enough to get a chance to see and photograph the northern lights. I have seen many occasions where people have left too early and given up, only to have the aurora come out an hour later. The best time to see the aurora is around solar midnight, which is the time when the sun is directly on the other side of the planet from your position. It does not necessarily correspond with local midnight. You need to generally be out for about six hours to give yourself the best chance.

For tips on how to plan your trip, check out our blog post on How to Plan your Aurora Borealis Vacation – Six Essential Considerations.