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They're back! After five years of relative quiet, the Northern Lights—the Aurora Borealis—have been on fire lately. This past year has witnessed a dramatic spike in the solar activity that ignites auroras, and this winter may offer the best viewing, and photographic opportunities, in nearly a decade.
I should probably warn you at the outset—I'm an unapologetic aurora junkie. Over the past 10 years, I've made a dozen or more journeys north to see, and photograph, the Northern Lights in locations across the Arctic. Why the obsession? Simple: The aurora ranks among the most spectacular natural events anywhere. I guarantee, once you've seen it, you'll be hooked, as well.
I've had the aurora bug since a memorable trip to Arctic Canada in 2002 when we saw more clouds than we did Northern Lights. But, finally, after five days, the weather broke, revealing an all-night light show—shimmering curtains of light and color danced and skipped overhead, sometimes slow and undulating, while at other times snapping like a celestial whip. The lights were mostly emerald green, occasionally tipped with violet and utterly breathtaking. Beneath a dancing sky, we enjoyed a New Year's Eve I'll never forget; that night has lured me back north every chance I get.
For the past five years or so, however, things have been pretty quiet in the northern skies. Blame the sun; for reasons that baffle scientists, auroras run on an 11-year cycle, corresponding to the activity level on the solar surface. The low ebb of that cycle—the solar minimum—was in 2008, and activity, which is measured by the number of sunspots and accompanying solar flares, has been building since then. The good news is that there already have been dozens of spectacular aurora events since the beginning of 2011, and there are almost certainly more to come.
Needless to say, I'm pumped for the coming season, and I'm gearing up. So if seeing, and photographing, the aurora is on your Bucket List, this may be a great year to go. The following tutorial is designed to provide you with what you need to know, where to go and how to bring back some of the most amazing pictures you've ever taken. Just don't ask me to predict the weather!
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Kevin Schafer is adamant about not adjusting images in Photoshop. This image shows the un-enhanced colors of an especially vivid aurora. When the conditions are just right, amazing light shows can be seen.
The Northern Lights are caused by charged particles thrown off by the sun during periods of intense solar activity. As these particles, e.g., the "solar wind," enter the Earth's atmosphere, they excite the gas molecules in our upper atmosphere, primarily oxygen and nitrogen, causing them to emit light. The more powerful the solar activity, the brighter and more lively are the resulting auroras here on Planet Earth.
Although auroras can appear to dance just overhead, they actually happen very high above the Earth, from 50 to 200 miles up. Most are lime green in color, but also can turn intense shades of purple and red. Keep in mind, though, that not all of the aurora color is visible to the human eye. Some of the intense reds you see in pictures are much less vivid in person, but are intensified with camera time exposures.
Where To Go
The best aurora viewing is within a donut-shaped band, the Auroral Oval, that circles both ends of the globe (the Southern Hemisphere has its own show called the Southern Lights, or Aurora Australis). The Oval passes directly over places like Fairbanks, Alaska, Yellowknife, Canada, and Reykjavik, Iceland, making all three excellent choices for auroras. During periods of intense auroras, the Oval expands, allowing the lights to be seen over a wider area. It takes a truly massive display, which may happen no more than once or twice a year, for the aurora to be visible in the Lower 48.
|Online Aurora Resources
There are a number of websites that can help with research and planning for an aurora trip. Some have alert services that will email you—or make a phone call—if activity is expected. Here are a couple of sites that I always have on my Bookmark Bar.
• Aurora Forecast. From the University of Alaska Geophysical Institute, this site lists expected activity levels for the next one to seven days. Also check out their Aurora Forecast iPhone app. www.gi.alaska.edu/AuroraForecast/
• NASA. For more information on the aurora and a map of the Auroral Oval, visit NASA's aurora web page at nmp.jpl.nasa.gov/st5/SCIENCE/aurora.html.
• Spaceweather.com. This site lists solar activity, as well as many other celestial events, and posts a gallery of recent aurora photos from all over the world. Got some good aurora pictures? You can post them here.
Wherever you go, the first thing you need to do is get out of town; the biggest barrier to good aurora photography is light pollution. There are a number of remote lodges that cater to aurora-watchers (see the "Lodging Options" sidebar). Otherwise, stay in town, rent a car and be prepared to drive to a nighttime location that you've scouted during the day. Sleep? Forget it—auroras can last an hour or all night; if they're really cranked up, you're not going to get to bed until nearly dawn.
When To Go
The aurora can occur any time of year, but in the Land of the Midnight Sun, you're not going to see much between May and September. Just why this should be the case isn't entirely clear, but whatever the reason, these seasons also have the benefit of longer days and milder weather, and offer more things to do when not gazing skyward.
The greatest challenge for sky-watchers is the weather, of course. You can easily spend a week staring up at the bottom of a solid bank of clouds, tortured by the certainty that there's a dazzler going on somewhere up there, but you can't see it. When picking a location, check weather data to see what months tend to have more cloudless nights and then keep your fingers crossed.
Some people prefer to avoid the full moon, whose brightness can diminish the intensity of aurora displays, but moonlight can add a wonderful luminosity to a snowy landscape.
The truth is, the best time to go after auroras is when something is happening on the surface of the sun, a fact that makes it difficult to plan a trip very far ahead. There are a number of websites that track sunspots and "solar weather" and can help predict aurora activity. If you're flexible, wait until you see a stretch of clear weather in the forecast and snag a cheap, last-minute flight north.
Shooting The Lights
If all goes well—the skies are clear and the aurora forecasts are looking good—it's time to get ready. It may seem obvious, but you're going to get cold doing aurora photography—really cold. Winter temperatures in aurora country regularly drop far below freezing, and you'll need to be properly suited up to work outside. On one aurora trip I took to Canada's Northwest Territories, nighttime temperatures hovered around -40 degrees F, cold enough to freeze and crack my cable release.
Besides winter clothes, you need to winterize your camera. Lithium batteries are the best choice for cold weather, holding up much better than alkalines, which can lose their charge in less than an hour at subzero temperatures. If you must use alkalines, carry a spare set in your pocket and be prepared to switch them out to keep your camera running. Also consider bringing along some chemical heat packs, for both you and your camera.
There's no ideal lens for aurora work, although wide-angle lenses do a better job of capturing displays that often can fill the sky. And choose one with at least an ƒ/2.8 opening—ƒ/2 or less is even better. My lens of choice is often my 28mm ƒ/1.4, which captures a large part of the sky with my full-frame Nikon D3, and is fast enough to give me the shortest possible exposure times. Remember, the difference between an ƒ/1.4 lens and an ƒ/5.6 lens is three full stops—in other words, between a 10-second exposure and an 80-second one.
Wide-angle lenses also allow you to include some foreground details, such as treetops, a tent or a cabin. I've found that most aurora photographs are improved by the addition of something earthbound for reference. Besides giving a sense of scale, a foreground also gives a much better sense of place than a simple sky picture. I normally look for an attractive grove of trees or a range of mountains, but you also can include a tent or a firelit cabin. Either way, plan ahead—scout locations before the sky gets dark, and you'll get better results.
The key is to remember that you're not just shooting the sky—you're creating a landscape composition in which the aurora is just a part. When I'm shooting the aurora, I'm constantly recomposing, moving the tripod and switching from vertical to horizontal, depending on the changing shape of the display. When the lights are really moving, they change shape—and your composition—every second. It can be busy out there.
Before your first night outside, get your lenses ready by turning off your autofocus—AF doesn't work well in the dark—and tape your lens at infinity to make sure you don't accidentally knock the lens off focus. Make sure you've taped the lens at actual infinity, not just at the symbol on your lens—each lens reaches infinity in a slightly different position. I recommend prefocusing before it gets dark at any distant object more than 100 feet away with whatever lens you plan to use and tape it there.
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When it comes to exposures, getting a perfect image is largely a matter of trial and error. Aurora displays can vary dramatically in brightness and activity, even during a single evening. The following chart will give you some useful starting points; however, your actual exposures may need to be longer or shorter.
Sample starting times for different ISOs and lens ƒ-stops:
As a rule of thumb, shorter exposures produce the best results. If you can keep your exposures to 15 seconds or less, you have a much better chance of stopping the motion of the lights, giving them definition. Longer exposures make for fuzzy, shapeless auroras and longer star streaks.
Hint: Check your exposures in the field by checking your histogram rather than the image on your LCD. In the dark, images often can look brighter on the screen than they really are. Aim for a graph with data primarily in the middle, not clumped at either end.
Kevin Schafer is primarily a wildlife photographer, but is also an Aurora addict. For more information and to see more of Kevin Schafer's work, visit www.kevinschafer.com.
• Alaska. In Alaska, have a look at Chena Hot Springs near Fairbanks, www.chenahotsprings.com, or any small out-of-town lodges and B&Bs. Wherever you go, choose a dark-friendly location, without a lot of stray light sources.