Tutorial 7
Photographing the Northern Lights

When people who live in temperate climes think of the North, what images come to mind? Igloos, polar bears, reindeer, Santa Claus possibly - but almost always, somewhere on the short list will be the Northern Lights. Even for people who see them year after year, the magic never ends, and many of those who live in well-lit cities will seek out dark spots to get a better view of them.

For hundreds of years, artists have attempted to capture the Aurora in watercolours, oils, woodcuts, etchings and almost any other medium you can imagine. Although the development of photography now allows anybody to create beautiful images, very few people have good photographs of the Northern Lights - here are some techniques to help you capture them on film.

Contrary to popular opinion, it doesn't require a huge investment in equipment to get quality images of the Aurora - a 30-year-old Pentax Spotmatic bought from a garage sale for $75 will be able to get you results that will match those from computerized outfits costing 20 times that much. The "secrets" are simply finding out some basic information, setting your camera up properly, and then having good luck, and probably some late lights!

A tripod for your camera, while not mandatory, certainly makes life easier. Your camera has to be held absolutely still during the long exposures required to record the lights, but an effective replacement for a tripod can be as simple as a bag full of beans, which you then nestle the camera down into. If you are using a tripod, a simple way to prevent getting 'burned' by the cold metal is to tape a piece of water-pipe insulation around the legs where you normally carry the tripod.

Some of the basics:

- Use your lens' widest aperture - the smallest f-number. Depth-of-field is not an issue when shooting the aurora, and the tiny loss in quality at f1.4 is more than made up for by the speed you gain;

- If you have a camera with lots of automatic features, turn everything possible to manual. In particular, turn off auto-focus, as it doesn't work in night-sky photography - set the focus at infinity;

- The choice of film is wide open; a mid-range ASA (ISO) such as 200 or 400 works well. Going to high-speed film such as ASA 1000 will result in grainy photos which seldom look good with this subject;

- Use a cable release, timer, or some other method to prevent jarring the camera when you trip the shutter;

- Record your exposure settings - it takes some experimentation to find the right exposure under widely-varying light conditions, and if you don't write it down, you're back to square 1 every time;

- Whenever possible, include a foreground - frame the Lights with trees, get them reflecting in a lake, the possibilities are endless.

I find that there are no advantages, and several disadvantages, to having any kind of filter on your lens. To put one of the disadvantages in scientific terms, Dick Hutchinson reports that:

With my Nikon lenses I have found that long exposures result in concentric circles showing up in the middle of the images when I use a filter of any kind. Nikon says this is due to the high reflectivity of the aurora. Thanks to the University of Alaska forecaster, the explanation follows. "These are interference fringes due to the parallel faces of the filter and to the narrow spectral emission at 5577 Angstroms in the aurora. That green, atomic oxygen emission line is the strongest emission in the aurora near our film and eye peak sensitivity, so it shows up first when there is any device in the optical path which sorts out the spectral emissions." So, don't use filters!

For many more Aurora Borealis resources and photographs on the Internet, see the Aurora Borealis links page. In particular, the photograph albums posted by Dick Hutchinson and Jan Curtis are tremendous sources of both information and inspiration.

Suggested starting points for photographing the Northern Lights

The exact exposure will depend on many factors - bracket your exposures from these starting figures as needed.

Source: Explorenorth.com; written by Murray Lundberg