Photographing aurora borealis is a thrilling experience
By Mark Collier
Staff Writer | July 21,2013
Mark Collier / Staff Photo
The aurora borealis hangs in the northern sky, creating a pink and purple splash over Wrightsville Reservoir in Middlesex.
Like most people, when I thought of aurora borealis, it was always in the context of a snow-draped forest and majestic peaks silhouetted against the brilliant, colorful chaos of a sky awash in swirling light and color.
As a matter of fact, it just never occurred to me that one might view this amazing natural light show south of the Arctic Circle until I saw a set of images taken by fellow Times Argus photographer Stefan Hard. As I look back, I now realize that was the moment my obsession with northern lights took root.
The process of photographing the aurora is, as it turns out, not all that complicated. With a little luck, research, advance planning, a tripod, a wide-angle lens and a relatively modest camera equipped with manual exposure mode, anyone can capture Mother Nature’s preeminent light show.
The aurora is caused when charged particles ejected from the sun collide with Earth’s atmosphere. Energy in the form of light is released, which we see as the aurora.
Because most of the particles ejected from the sun are deflected by Earth’s magnetic field, the phenomena is generally seen in the far north and far south near the poles, where the magnetic field is weakest.
The best chance to see the aurora is following a coronal mass ejection, which happens when a large mass of plasma and other material are blasted out into space from the sun toward Earth.
The first step in photographing northern lights is knowing when it may be visible and active (combined with a healthy dose of luck).
Fortunately for those who do not have a satellite continuously monitoring the sun’s activity, a number of websites and apps are available to keep skywatchers abreast of potential aurora activity.
Some handy apps available to help the aurora photographer are Aurora Forecast available for both IOS and Android, and Aurora Buddy for Android.
The activity level of the aurora is measured by the “Kp Index” on a scale from 0 to 9. Because the lights are not evenly spread across the sky and tend to clump in pockets, the Kp Index is the average reported from a number of observation stations spread across the hemisphere.
For the aurora to be visible as far south as Vermont, the number generally needs to fall between 4 and 9. The higher the index, the farther south the lights are visible.
Once it becomes clear the aurora is active, the next step is finding a good location for observation and photography. The best spots are located away from sources of light pollution like cities and towns. It is not a bad idea to scout potential locations during daylight hours, noting the site for those times when the aurora is active and visible.
Once one arrives at the chosen location, it is important to set up the camera and tripod so they are facing north / northwest.
Depending on how energetic the aurora is, visibility may range from very faint and not visible to the human eye to very bright and downright spectacular. When the aurora is very faint it may be imperceptible to the human eye. This does not, however, mean it cannot be photographed.
To make sure the light show is in focus, put your camera in manual focus mode and set the lens focus to infinity. This is the little “figure eight” symbol that appears on the lens’ distance scale when the focus ring has been rotated all the way to the right.
For exposure settings, I usually start with the aperture set to F5.6 and an exposure of 20 seconds. Depending on conditions, you will want to vary the aperture and length of exposure.
As with most photographic endeavors, ultimate success is going to be realized through patience, experimentation and, most important, getting out and taking pictures.
When you do take some photos and please share the results with us at www.timesargus.com or www.rutlandherald.com.
Mark Collier is a photographer for the Barre-Montpelier Times Argus and Rutland Herald.