You will need a flashlight or head lamp because out in the cold away from civilization at night, it can be very difficult to see. You will likely need to change your camera’s setting depending on lighting conditions and you will not be able to easily find the buttons in the darkness. Be aware that you will likely be in a group of other photographers and the light from your head lamp or flashlight can ruin their photos and vice versa. A red lens cover will dim your lamp and help prevent this, but always be cognizant of where you’re pointing your lamp.
ISO (sensor sensitivity). Generally speaking, you want to raise your ISO as high as your camera will allow while still producing clean and usable photos. This will depend on the camera you’re using. Generally, the larger the sensor, the higher you will be able to set your ISO, but results will vary depending on the ambient lighting conditions and your camera. That being said, with an APS-C size sensor, you should be able to push the ISO up to 1600 or 3200. With a full frame sensor you may be able to raise your ISO up to 6400 or higher and still produce usably low noise photos.
Shutter Speed. You’ll be tempted to brighten your photos by using a slow shutter speed; we don’t recommend it. Try raising your ISO and quicken your shutter speed. The Northern lights dance in the sky in waves that resemble magnetic field lines. To capture their crisp edges and prevent the Lights from looking like green blobs, you’ll want as fast a Shutter speed as you can get without cranking your ISO so high your photos are noisy messes. For example, shutter speed of 3 seconds with make the Northern Lights look much more crisp and appealing than a slower shutter speed of 15 seconds.
Aperture (F-stop). Each lens is manufactured with physical F-stop limits. Generally speaking, a lens with a lower F-stop number–which is considered a faster lens, will perform better when photographing the Northern Lights. Why? Because the faster lens allows you more freedom with ISO and shutter speed. A faster lens allows more light to enter the camera, which means you won’t have to crank that noisy ISO sensitivity as high to use a faster shutter speed. Choose a lens with an F-stop of at least F4. Ideally, you want a lens that is as fast as F2 or F1.4, but a faster lens is usually more expensive.
Focal Length (how wide or zoomy your lens is). Unless you’re an amateur enthusiast or a professional photographer, you probably don’t have a camera case full of lenses for different situations. So the question is, do you have the right lens for Northern Lights photography? The answer is yes, it’s likely wide enough but no, it’s likely not fast enough. Nearly all “kit” lenses that come with cameras are 18-55mm. If you have an APS-C size sensor, that 18-55mm is a 29-88mm full frame equivalent on your camera. A useful range, but you’re trying to compose photos of landscapes with a considerable amount of sky. Wider is better. 29mm may be wide enough but your kit lens may only be as fast as F3.5, and while that can perhaps get the job done, your shutter speed will likely have to be slower to compensate. The result is your lens will produce blob like Northern Lights without those beautifully crisp edges. Again, your budget will dictate what you can afford.
An out of focus Northern Lights picture will be a real disappointment when you view your photos on your computer. Usually focussing isn’t an issue. In normal, everyday lighting conditions, you just point your camera and the autofocus does the rest. Unfortunately, cameras don’t do well focusing in darkness and that is exactly where you will be photographing Northern Lights. You will need to set your camera (or lens’) focus to manual. Even manual focusing can be tricky when its dark and you can’t see anything through your viewfinder, so there are three things you can try.
Hyperfocal distance. This is the distance at which the lens focuses where everything more distant is acceptably sharp (or in focus). This can be tricky and I would suggest researching and practicing with your equipment before you’re on your expensive excursion.
Light painting objects in the foreground. Your photos of the Northern Lights will be better with foreground objects because they create depth and show size and add to your composition. If you can’t see a tree clearly enough to focus it manually, try shining your flashlight on it (painting it with light). You can light it up, focus, and turn your light back off while waiting for the Northern Lights.
Point-focusing on stars or faraway lights. This is the easiest of the three. Find yourself a bright star or distant city light and focus on that. Get the light as point-like as you can. Once you have the lens focused, leave the lens setting alone. You can even bring tape with you to affix your lens focus ring exactly where you want it.
Use a tripod and a timed shutter release.
When taking long exposure photos of any kind, handshake can cause your pictures to be blurred. To prevent handshake use a tripod. The tripod will steady the camera while the shutter is open. With your camera’s timed shutter release, the camera will release the shutter 2 to 10 seconds after you push the shutter release button (depending on your cameras settings). In that time, any vibrations or movement caused by your hand touching the camera should subside.
Bring extra batteries.
Battery life is considerably shortened by freezing temperatures. Your battery indicator will go from full to empty in minutes as your camera body approaches zero degrees or colder. You can bring your battery back to life by warming it in your pocket next to your body, but you’ll need a few spare batteries in the mean time.
The Northern Lights are most active between 10:00 PM and 2:00 AM. You may be out on your Northern Lights excursion for hours without seeing anything. When the sky finally becomes active, it may only last ten minutes.
Your excursion company may provide you with overgarments to keep you warm, but the most important piece of your ensemble will undoubtedly be your boots. Wear warm boots! In fact, wear boots warmer than you think you’ll need. You may find yourself standing on frozen ground for hours. Once your boots, and then your feet get cold, you will be miserable.
The Northern Lights can invoke a spiritual experience and a sense of scientific wonderment. Take a moment to remove your eye from your camera’s viewfinder and look up.