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DANCING SKIES |
The Aurora Borealis is
a sight that almost every nature photographer dreams of capturing
someday. It is not something that can be approached casually.
It has to be earned. For one thing, it can't hardly be
photographed on a summer vacation because the sky never gets dark
enough in the Arctic or Antarctic at this time of year. Because
it is an element of extreme latitudes and is often associated with
extreme cold, the Northern Lights have been photographed by relatively
few serious photographers. Seeing the night time skies burst into
cold fire is more than worth the extra effort and enduring a little
discomfort.
 Photographing northern lights doesn't
require much in the way of specialized equipment. The most
important thing is a desire to experience the wonders of nature.
Although a tolerance for cold can be a big help as well since
some of the best viewing occurs at the tail end of winter in the far
northern latitudes. The newer digital SLRs are perfect for this
job because they handle noise so well at higher ISOs. The only
other equipment you need is a tripod and a wide angle lens. A
small flashlight and a cable release are nice to have, but not
absolutely necessary. The self-timer can substitute for the cable
release, but then you have a delay, and the lights can change quite a
bit in a few seconds.
The technique is pretty much the same as photographing the night sky without the aurora. Set your lens on Manual Focus and focus almost to infinity. Set the camera Mode on Manual. Start with the ISO on 400. Open the aperture pretty much as wide as it will go--2.8, 3.5 or whatever. Start with a shutter speed of 15 seconds. Review the first couple of images. If they are too dark, raise the ISO to 800, and/or slow the shutter speed to 20 seconds. Some photographers prefer to use an ISO of 1600 and a faster shutter speed. Feel free to play with this and see which results you prefer. Keep in mind that the wider the angle of your lens, the longer the shutter can stay open before the stars begin to streak noticeably. At 100mm you have no more than 10 seconds. Even at 20mm, you have no more than 25 seconds. Also, the wider your lens, the more depth of field you're going to have, and since the aperture is wide open, depth of field is going to be minimal. Therefore, you want to be careful about including important elements in your image that are close to the lens. Either those close elements or the aurora are going to be blurry.  You want to pick a location with very
little artificial light, a location with dark skies. We've had
some of our best photography with a partial moon--half moon or smaller.
A bit of moon provides enough illumination to light up the
foreground, and this makes it much easier to compose images at night.
A full moon can be so bright it washes out some of the stars, but
the aurora is usually so bright the moon does not affect it noticeably.
Because of the high ISOs and long exposures, noise can still be a problem even with the best cameras. The resulting images are often fine for website or computer use, but for publication or making prints we process them in 16 bit rather than 8 bit, and we run them through a noise-reduction program. We use Noise Ninja, and we have been happy with the results. Now get out there and have fun with some nocturnal landscapes. |