“Quick! The Aurora is out! What settings should my camera be set to?”. It’s the most frequent question I see online when there is a geomagnetic storm in progress or in the immediate forecast. Unfortunately, it’s a bit of a loaded question. Not all cameras or sensors are the same and the aurora is a very dynamic phenomenon; there is no simple answer. This article is about getting to know and understand your camera settings to give you a starting point on aurora photography. If you feel comfortable with camera settings in general you can skip to the examples at the end.
This guide is based on how I shoot the aurora, the way I operate my camera at night, and the thought process I go through. These aren’t rules to follow, but suggestions to get you started so you can find what works for you and your camera system. Here goes . . .
What kind of camera do you need?
Many different cameras can capture photos of the northern lights. Any camera that you can put on a full manual setting, or “M” and be able to manual focus; all DSLRs, mirrorless, and some compact cameras will work. It’s nice to have a wide angle lens so you can get as much of the sky into the frame as possible.
What controls will you have to use?
The three absolutely essential camera controls you need to know and understand are:
- Aperture – the amount of light coming into the camera
- ISO – how well your camera uses incoming light
- Shutter Speed – how long light will enter the camera for
The aperture setting is the easiest decision for me when shooting aurora. I use the lowest setting possible. The aperture is the size of the opening in the lens. The highest aperture setting (or f-stop) corresponds to the smallest opening; at the lowest f-stop the aperture is wide open allowing the most light in. It’s worth noting that many lenses may have higher optical aberrations at their lowest f-stop (chromatic aberration and vignetting are typical), so it’s worthwhile testing this with your lens to see what you find acceptable.
Most kit lenses that come with a DSLR will have the lowest f-stop around f/3.5. There are a good number of mid-price, wide-angle lenses that are f/2.8 and some (usually pricey) at f/1.8 or f/1.4. The benefit of using a higher aperture setting is that you get a higher depth of field (greater distance range in focus), which typically isn’t as important when shooting the aurora.
I usually change the ISO setting very little while shooting aurora. The ISO setting controls the sensitivity of your camera’s sensor. Think of the ISO as an amplifier, and just as an amp can take a low volume voice and blast it over a whole stadium, a high ISO setting can take a tiny bit of light and practically turn your camera into night vision goggles. This is nice because a high ISO setting means you can use a faster shutter speed and capture more detail in fast moving aurora. There is a price to pay for this amplification in the amount of electronic noise as well as a reduction in color and contrast.
The quality your images from the ISO setting is probably the most variable control across different cameras (and the largest benefit to having an expensive one). You will need to find that “sweet spot” that balances ability of speed and image quality. For instance, my Nikon D7000 looks fairly good at an ISO up to 1250 for night images, but really starts to suffer at 1600 and up [The more current Nikon Nikon D7200 or even Nikon D7100 24.1 MP slightly edge out the older model in ISO performance]. Photos from the Nikon D4 or Canon 5D Mark III push a pretty decent image quality up to ISO 3200-6400 (and up). My Nikon D90 starts to suffer above ISO 800.
I suggest testing in a dark room. Take a series of photos slowly increasing the ISO setting (bringing down the shutter speed or increase the aperture as you do to keep exposure consistent). Review them in whatever post-processing program you use and see what you can accomplish with noise reduction (see my articles on noise reduction and white balance – simple, intermediate). While there are a lot of programs out there that do a good job at reducing grainy ISO noise, you’ll always lose detail when you use it, that’s why I like to know what to expect before going out in the dark.
If you want my quick answer for ISO setting, considering a mid-range DSLR with an f/stop in the f/2.8-3.5 range: ISO 640-1600 should produce an image of reasonable quality. For high end cameras (like Nikon D4 or Canon EOS 5D Mark III) an ISO of 3200 – 5000 can yield quite good results.
In my opinion, the shutter speed is the most important thing to think about while shooting the aurora. The longer your camera’s shutter stays open the longer light hits the camera sensor . You’re probably using the lowest aperture setting, you have a fairly limited range to work with for ISO, but reasonable shutter speeds for aurora photography can be a fraction of a second up to as long as your camera will let you (typically 30 seconds without a manual release). The thing to keep in mind is motion. Taking a 5 second long of an exposure of a race car driving by is going to be a blur, the concept is no different for aurora. If it’s not moving fast, diffuse, or just sitting on the horizon it’s easy to get away with a long shutter speed. That can allow you to decrease the ISO setting and get a higher quality image. On the other hand, during a strong geomagnetic storm the aurora flickers and dances with pinks and reds shooting through, rays and coronas form and disappear on millisecond timescales. With a long exposure all of that wonderful detail is lost. That’s when I really crank up the ISO and take the shutter speed to as fast as I can, sometimes to less than 1 second!
Even at night you can get too much light and overexpose your photos. The camera’s sensor is more receptive to the green emission lines from the aurora than your eye. It can be easy to use too long of a shutter speed so that your sensor is over-saturated by that light. Often this makes that green aurora look too bright or even white (all details are lost) in the photo. It’s hard to come up with a simple rule to prevent this – you’ll just have to watch the monitor (or better, the histogram – article forthcoming) on your camera until you figure it out.
What’s the scene? Think about what the aurora is doing! Here are a couple examples:
1) A diffuse (dim) aurora that sits barely above the horizon with no visible motion or structure?
- Go for a longer shutter speed, there are no details to capture.
- Longer shutter speed means you can decrease the ISO for less noise
2) It’s not even dark yet and the aurora is out! This is an extreme example, but it’s happened for me more than once, the aurora is bright enough to be seen even though there are barely any stars out. There’s more motion, but not much detail or color yet.
3) The aurora is directly overhead, moving incredibly fast, with a strong corona (diverging rays shooting up into the sky), pink lower borders are flickering across the sky. Think fast!
4) Activity is fairly high, there are multiple bands, but not quickly flickering quickly across the sky. The motion is reminiscent of steam coming out of a smokestack. The high altitude oxygen may be coming out to play casting a red or purplish hue above the green. This is kind of the typical “good” Alaska night, not the best we get to see, but certainly something to write home about.
I hope you find this helpful and that it gives you a jumping off point. My most important piece of advice: don’t glue your eyes to that camera! Take time to watch the aurora and really enjoy it. Go out, shoot, watch out for moose, and have fun. I’ll keep adding some more examples below with different camera/lens combinations below.
**Note there are more articles still to come on aurora shooting. Other important things at this point being focusing, understanding the histogram (more detail in getting exposure right), and using a tripod. For focus, you can start with a focus at infinity (simple), or find the hyperfocal distance for your lens (at given aperture and focal length). For now I can refer you to the Cambridge in Color site.**
All images copyright Lee W Petersen – Please contact for usage: firstname.lastname@example.org