After finally witnessing a total solar eclipse and declaring it the most beautiful thing I’ve ever seen, I started hearing people say things like, “Wait until you see the northern lights.” So when fellow pro photographer Don Smith and I planned an Iceland photo trip to prepare for our upcoming photo workshop, we chose January because it’s in the heart of northern lights season. Could the beauty of the northern lights really rival a total solar eclipse? (Spoiler alert: Yes.)
The Northern Lights Only Look Like Magic
The sun continuously bombards Earth with a “solar wind” of electromagnetic waves and particles. Each wavelength and particle in the broad spectrum of solar energy interacts differently with the atmospheric atoms and molecules it encounters. Some wavelengths bounce harmlessly back out to space; the narrow range of infrared and visible energy warms our days, colors our sky and lights our way; the ultraviolet wavelengths burn our skin; and the most energetic solar energy alters the atoms and molecules that cause an aurora.
The solar wind’s electromagnetic particles and its highest frequencies contain enough energy to strip electrons from atmospheric atoms and molecules, creating a charge imbalance called ionization. The majority of this super-charged ionizing radiation is emitted by coronal mass ejections, solar storms that send energized particles hurtling toward Earth.
Instead of penetrating our atmosphere to create havoc below, most of the sun’s ionizing radiation is deflected by the magnetosphere, Earth’s protective magnetic shield. Constant bombardment from the solar wind makes the magnetosphere teardrop-shaped. The battered side facing the sun is compressed and spread horizontally, while the shielded side stretches like a tail behind Earth, thinning with distance.
As Earth rotates, our daylight side is always behind the magnetosphere’s thin but densely compressed region, while the night side looks out through the magnetosphere’s more diffuse extended region. Just as the upwind side of a wall or building shelters whatever is directly behind it, the sunward side of the magnetosphere channels ionized particles to the upper regions of Earth’s leeward (night) side.
These atmospheric machinations spread an oval of aurora-causing geomagnetic activity high in the atmosphere, always on Earth’s night side. The size and intensity of this ovular aurora region vary daily (and, on a smaller scale, by the hour or minute), corresponding to the intensity of the solar energy reaching Earth. The larger it is, the lower the latitude an aurora will be visible.
Green is the dominant aurora color, but the color can vary with the atoms and molecules involved and their altitude. Oxygen creates a green and sometimes yellow aurora, while nitrogen produces red, violet and blue. Greens appear at elevations below 150 miles; above that, red dominates. Blue only appears in the lowest altitudes.
Aurora Prediction: Kp-Index
As with any terrestrial weather event, there’s no such thing as an aurora “sure thing”—the best we can do is put ourselves in position to be as close as possible to the auroral oval on nights with the greatest chance for auroral activity. Winter is best because the nights are both longer and darker, so planning a winter trip to the high latitudes (the higher, the better), like Iceland, is a great start.
Just as important as getting to an area favorable to aurora displays is understanding and monitoring the Kp- (or K-) index once you’re there. The Kp-index is a 0 to 9 scale of atmospheric electromagnetic activity, with 0 being little or no activity (get some sleep) and 9 being the most extreme activity (don’t forget your sunglasses).
Many governments and scientific organizations issue regular Kp forecasts that seem about as reliable as a weather forecast—pretty good, but far from perfect. There are many websites and smartphone apps that will provide you with virtually real-time Kp forecasts for your location—some will even issue alerts.
Making It Happen
Armed with more knowledge than experience, Don and I followed our guide into Iceland’s exquisite winter landscape with visions of auroras dancing in our heads. We were grateful that our guide was an Iceland native and excellent photographer with years of northern lights experience.
By day, we photographed all the winter-accessible locations on Iceland’s Snæfellsnes Peninsula and South Coast, especially enjoying the two-hour sunrises and sunsets, courtesy of a sun that never rose higher than 8 degrees above the horizon. And by night we bundled up and ventured into the frigid dark seeking an electric light show.
For our nightly aurora hunt, we’d drive to a location with a nice foreground, dark skies and a clear view of the northern sky. There we’d sit for a couple of hours (sometimes longer), periodically wiping the fog from the windows of our spacious Suburban and occasionally stepping into the cold darkness to scan the sky. Sometimes we’d take a test shot to check for color our eyes couldn’t see.
We quickly learned the fickle, frustrating nature of aurora hunting. Nights with potential were stifled by clouds; nights with clear skies were Kp washouts. With just two nights in Iceland remaining, I started to feel a little anxious.
The final two nights would be spent near Glacier Lagoon, a magnificent ocean inlet dotted with floating icebergs, a patchwork of thin ice, and reflective water that combined for an ideal foreground for the northern lights.
The forecasts for Wednesday, our penultimate night, were clear skies and a 1 or 2 Kp index. Not great, but the best weather/Kp combination of the trip. And our guide assured us that even Kp 1 can deliver an aurora, and Kp 2 can be a very nice display. Pulling into the Glacier Lagoon parking lot beneath a beautiful star-studded sky, we saw no aurora. So we waited.
Soon we saw what I declared a thin fog forming above the lagoon, but the guide insisted it was the beginnings of northern lights, so we followed him down to the shoreline. Dubious, I clicked a long exposure, and waited for the image to pop onto my LCD. I was thrilled (understatement) when my image revealed a distinct green haze above the lagoon: My first view of the northern lights!
We spent the next couple of hours photographing that low-hanging green haze, occasionally infused with hints of red. That night’s aurora never rose more than 20 degrees or so above the horizon, and except for just a few minutes at its peak, had no real definition. Little did I know that the show that night was just a warm-up for the next night’s experience.
The Kp forecast for Thursday night was 4 or 5, which our guide promised was perfect because anything more than Kp 5 can be too bright. The weather was a different story, and all we could do was watch and hope as the clouds ebbed and flowed all day. Despite a nearly 100 percent cloud cover at sunset, we exited dinner to a ceiling of stars and beelined back to Glacier Lagoon.
Waiting in the lagoon parking lot, we could see a faint aurora but stayed in the car because, “This is no better than last night.” (One success, and we’re already aurora snobs.) What might look promising one minute would all but disappear the next. Then we noticed new activity in the northwest sky that went from 0-to-60 so fast that we bolted down to the lagoon like Keystone Cops. By the time my gear was set up, the sky had transformed into a green and red psychedelic extravaganza, and we were in business.
The next several hours were a blur as I witnessed what was quite possibly the most extraordinary sight of my life. Starting in the western sky, across the lagoon, the show gradually moved south (defying all my expectations), forcing me to constantly shift further up the lagoon to keep ice and water in my foreground.
With my head on a swivel, I saw colored tendrils stretch skyward, some touching both the east and west horizons, others slowly pulsing, spiraling, and doubling back until I felt like I was inside a giant lava lamp. The motion was like the minute hand on a clock—not apparent at any given instant but obvious if I kept my eye on one feature for just a minute or two.
At one point, I tore my eyes from the spectacle above the lagoon and saw the entire eastern sky behind me ablaze with tangled green ribbons so intense that I instantly grabbed my gear and scrambled up the snowy hill for a better view in that direction. Over the course of maybe 20 minutes, that display rocketed heavenward, filling the entire eastern sky from horizon to zenith, slowly drifting north and finally to the west and back over the lagoon, forcing me to race (and tumble) back down the hill.
When the display showed signs of waning, I slowly made my way back to the car, shooting along the way. The show that night lasted for hours and was still going when we finally decided to head back to the hotel to count our riches.
Lessons Learned Photographing The Northern Lights
- Bundle up. Winter nights in the high latitudes might just be the coldest temperatures you’ve ever experienced—dress accordingly because few things will shorten or distract a great shoot faster than cold. In addition to a robust, hooded down jacket, I was comfortably toasty in a wool hat, balaclava, wool base undershirt, fleece shirt, thermal long-johns, lined pants and/or (sometimes) insulated powder pants, thin liner and heavy gloves, wool socks and insulated boots.
- Bring extra batteries (more than you think you’ll need) and keep them warm. In extreme cold, lithium-ion batteries can go from 50 percent charged to exhausted in minutes. It’s best to store batteries next to your body and/or close to a heat source, like a heated glove or hand-warmer pouch. And when a battery runs down, it may be reusable once it’s warmed.
- Learn how to control your camera in the dark. Not just exposure, composition and focus but also how to display and magnify an image on your LCD by touch (to check focus).
- Pre-scout your locations when possible, looking for a striking foreground to go with your aurora. Remember, while the northern lights tend to concentrate in the northern sky, an intense display can appear in any direction, so the more direction options your location option has, the better your chances.
- The aurora photography goal is to capture sky color and foreground detail, but your exposure will vary a lot with the aurora’s intensity and the amount of moonlight (which isn’t necessarily a deal-breaker as it can be for the Milky Way). Monitor your histogram constantly—unlike Milky Way and other night photography, aurora exposures can change by multiple stops in minutes and sometimes seconds. An exposure that worked one minute may completely blow out the aurora the next.
- Turn on your camera’s “blinking highlights.” I never base my final exposure decision on my camera’s highlight alert, but I do use it as a reminder to check my histogram in rapidly changing light—this saved me several times during that intense aurora shoot.
- If the aurora is fairly static, more of a homogenous color in the sky, shutter speeds up to 30 seconds won’t be a problem. On the other hand, if you’re photographing shifting curtains and tendrils of intense color, you’ll want to limit your shutter speeds to 10 seconds or faster to avoid blurring the rapidly changing aurora detail.
- The extreme cold seemed to prevent my sensor from getting too hot, allowing me to push my ISO a stop higher than I normally would.
- With a great foreground right at my feet, depth of field became more important than it is in most of my night shoots. Check your focus each time you change your focal length—a night image that appears sharp on your LCD may be soft when viewed on the computer.
- A wide, fast zoom lens will probably be your best bet.
- Generally, you’ll want to give your frame at least two-thirds sky, but base your horizon placement on the relative beauty of the sky and foreground. Because I had such a spectacular foreground, my compositions skewed closer to 50/50 foreground versus sky.
- Shoot both horizontal and vertical frames.
- Move around to change your foreground, and try to coordinate the foreground features with aurora features. It’s easy to get locked into one location or composition because everything’s so beautiful, but remember that it’s probably just as beautiful over there or facing that direction.
- Even if you can’t see the aurora reflected in water, your camera might be able to.
And finally, take a few minutes to step away from your camera and appreciate the beauty you’re witnessing.