Ideally, for optimum results, you really need to understand manual settings on your camera. Here are some basics to get you going.
Before you start shooting:
White Balance (WB)
Shooting a lot of nightscapes (probably an understatement) means that I have my camera’s K value setting set to a value that suits most nightscape situations; this means I can just switch to K in the white balance option at night and the camera churns out images that look reasonably true to what the eye sees, so I know what I am getting. Often the WB will need a little tweak in post-production, warmer or cooler, but I find, certainly in the UK, I tend to have my WB set on 3800K.
Most cameras allow you to program a value measured in Kelvin into the K setting within the WB options. Please also refer to the previous “What to Look for chapter” for a visual representation.
When it comes to actually shooting, number one is focus, it’s amazing how many people get over exited and forget about this critical part, though it’s understandable. Naturally you need to shoot in manual focus, and a good starting focus is infinity (not over infinity), then, as most lenses are uncalibrated, for sharp stars, refine your focus (manually) on the brightest one by digitally zooming into it on your live view, or, you can use a light source that is 30-40 metres or more away.
Remember, if you have close foreground elements you wish to bring into focus within the frame, you need to either focus on these with a torch, refining in live view, or complete an exposure for the foreground, and the sky, and bring them together in Photoshop.
Use the widest aperture on your lens (smaller F number) to allow more light into the lens, unless you know this makes a mess of the stars (coma, aberration etc), in which case stop it down a little.
Now this one is completely variable depending on the intensity of the Aurora. Ideally, this needs adjusting as the Aurora intensifies, as a quicker shutter speed, allows detail to be caught in the movement of the Aurora, that said, if you are in the UK, and just have a glow on the horizon, you need to expose for the rest of the sky, so 20 seconds is a good starting point on a wide lens.
If the display gets brighter, and has movement, start reducing the shutter speed to capture detail/movement.
Again, the ISO is similar to shutter speed, you need to start at a high value, and reduce it accordingly as/if it intensifies if the display is weak.
Exact settings depend on camera, lens, and how much light is emitted by the Aurora. In the UK I have ended up working on settings such as ISO 1250/1600 and 2-8 seconds during more intense displays, further north, I’ve been all the way down to ISO 100 and 2-4 seconds; you have to learn to adjust both ISO and shutter speed whilst still balancing a well exposed image, both highlights, and the rest of the sky, foreground.