Camera Settings That Work in the Cold

Set the camera up indoors, before you go out. Everything below is much harder to do wearing mittens, in the dark, at minus fifteen, with a display happening that you are missing while you fiddle with menus.

Almost every guide tells you to lengthen the exposure when the aurora is faint. That is only half right, and following it blindly produces the flat green smears that fill photo sharing sites.

Shutter speed should follow the aurora's movement, not its brightness.

A quiet arc sitting still on the horizon will take twenty seconds happily and reward you with detail. The same twenty seconds during a substorm, when the curtains are rippling and reorganising every second or two, averages all that structure into a uniform wash. The bright, active, exciting part of the night is exactly when you need the shortest exposures.

So when the display starts moving, drop to two or three seconds and raise ISO to compensate. Noise is fixable. Motion blur is not.

Autofocus will not work. There is nothing with enough contrast for it to lock onto, and it will hunt back and forth until you give up.

The infinity mark on the lens barrel is not reliable either. Most modern lenses focus slightly past infinity by design, and the mark is approximate.

What works: switch to manual, point at the brightest star or a distant light, use live view at maximum magnification, and turn the focus ring until the star is as small as you can make it. Not sharp, small. Then tape the ring or note the position, because knocking it is easy and you will not notice until you look at the images at home.

Do this once, properly, at the start of the evening. Then check it again after each time you change a lens, and after any significant temperature change, because thermal contraction can shift focus slightly on some lenses.

• Batteries lose capacity fast. Carry two or three, keep the spares in an inside pocket against your body, and rotate them. A battery that reads dead at minus twenty will often recover in your pocket.
• Condensation is the real risk, and it happens on the way in, not out. Bringing a cold camera into a warm room covers it in moisture, including internally. Put it in a sealed bag before you go inside and let it warm up in there.
• LCD screens go sluggish and sometimes ghost badly. Nothing is wrong; they recover.
• Lens frost builds up slowly on the front element. Check it periodically, because you will not see it through the viewfinder and you will only find it in the images later. A hand warmer taped near the lens barrel prevents it.
• Carbon fibre tripods are far less unpleasant to touch than aluminium at these temperatures. If you have the choice, take that one.

An aurora photograph with nothing but sky in it is boring, however good the display was. It needs something to give it scale and place: trees, a shoreline, a mountain, a cabin, a person standing still.

Which means choosing your foreground in daylight if you can, or at least arriving somewhere with a shape on the horizon rather than an empty field. Guides who work with photographers pick locations on this basis, and it is a large part of what a photography tour is actually selling.

If you want yourself in the frame: stand still for the whole exposure, have someone light you for half a second with a dim torch, and expect to try it several times.

A workflow, in the order things happen, because the order is where people lose frames.

1. Set up in the light. Aperture wide open, ISO 1600, shutter 5 seconds, manual focus, RAW, stabilisation off, self-timer on. Do this at the hotel.
2. Focus on arrival, on the brightest star, at maximum magnification, until it is as small as you can get it. Then tape the ring or note the position.
3. Take a test frame immediately, before anything is happening. Check focus at 100 percent on the screen. This is the last comfortable moment to discover a problem.
4. Frame for the foreground first. The aurora will move; the mountain will not. Compose on the landscape and let the sky arrive into it.
5. When it brightens, shorten the shutter. Two to five seconds during a substorm, and raise ISO to compensate. This is the decision that separates usable frames from green mush.
6. Shoot more than you think. The structure changes second to second and the frame you want is rarely the one you planned.
7. Check the histogram occasionally, not the screen. A bright screen in the dark makes everything look overexposed and destroys your night vision.
8. Bag the camera before going indoors. Sealed, with the cold air still in it, and let it warm up in the bag. Condensation forms on the way in, not on the way out.

Aurora files almost always need work, and knowing which adjustments are legitimate keeps you on the right side of a line that a lot of published images cross.

White balance is the first thing to fix. Auto white balance has no idea what it is looking at and typically renders the sky an unpleasant yellow-brown. Somewhere around 3500 to 4000 K is a sensible starting point, adjusted to taste.

Exposure and contrast next, gently. Aurora frames often need a small lift in the shadows to bring back the landscape, and heavy-handed contrast destroys the soft gradients that make a curtain look like a curtain.

Noise reduction last, and less than you think. High ISO grain looks worse at 100 percent than it does at any size anyone will view the image.

What separates processing from fabrication is simple enough: you are recovering what the sensor recorded, not adding what it did not. Pulling out green that was captured in a five-second exposure is processing. Compositing a Milky Way from another night, or painting in a colour the physics does not produce, is not. The second kind is common in tour marketing and it is the reason our page on aurora colours includes a section on spotting it.

• Camera settings follow standard aurora and astrophotography practice as published by national tourist boards and by working aurora photographers. The values here are starting points, not rules.
• The 500 rule for star trailing (500 divided by focal length in millimetres, giving approximate maximum seconds before visible trailing) is a standard field approximation.
• Emission colours that constrain what a genuine aurora photograph can contain: NOAA Space Weather Prediction Center.
• Cold effects on equipment: lithium-ion capacity loss at low temperature, and condensation on transition from cold to warm air, are general properties rather than aurora-specific ones.
• Conditions on the night: MET Norway, yr.no and the Icelandic Met Office.