The northern lights are on again. Here's the best way to photograph them.

Samuel Long / Pittsburgh Post-Gazette

Pittsburghers were treated to colorful auroras that blanketed the city’s night sky Thursday night. Luckily, the northern lights are back for a second wave.

Auroras are caused by magnetic storms triggered by solar activity such as solar flares or coronal mass ejections (CMEs), which are large expulsions of plasma and magnetic field from the sun’s corona, according to NASA. On the evening of Oct. 8, the National Oceanic and Atmospheric Administration Space Weather Prediction Center observed a fast-moving CME that reached Earth Thursday, sending a blaze of lights across Pittsburgh’s — and the country’s — night sky. 

What makes them sometimes difficult to see with the naked eye is the idea that our eyes process light information quickly, explained Shawn Dahl, a service coordinator for the NWS’ Space Weather Prediction Center. Cameras, on the other hand, collect information over time, making them a crucial tool.

When a geomagnetic storm in May caused northern lights to appear across the U.S. in a similar fashion, Joseph Timmerman, a 45-year-old civil engineer and photographer living in Mt. Lebanon, said he wasn’t able to take a picture of the lights, and felt as though he was left out.

But Thursday night, he was ready.

How do I determine the best location?

Timmerman said it’s important to find a spot with a nice, clear view toward the north. For him, that was Grandview Avenue on Mount Washington, where he took a photo and uploaded to it to his Instagram account.

“That’s where we were last night. It works very well because you can overlook the city towards the north and add the composition of the city lights with the aurora,” Timmerman said. 

But, the further north an individual can go (away from light pollution caused by the city), the easier it will be to expose their cameras for the northern lights, he said. Not to mention, lakes and other natural features are great for photo composition as well. 

What are the best camera settings to use?

Though it took a little trial and error, Timmerman said he was able to balance Pittsburgh’s city lights with the auroras by starting with a higher ISO, which controls how sensitive the camera’s sensor is to light. This allowed him to shorten his exposure time to around 6-10 seconds, which helped balance the two light sources.

A lot of landscape photography uses a wide aperture, but according to expert Serena Dzenis from Iceland Photo Tours, a wide aperture, near f/2.8, works best for auroras by allowing your camera to bring in as much light as possible. 

If shooting on a mobile phone with a camera, Timmerman said it’s important to use “night mode.” On most phone cameras, this mode extends the capture time and raises ISO similarly to the settings required on a professional-grade camera. 

The importance of timing

Timmerman said he talks with a group of photographers when brainstorming ideas of how best to capture auroras. Some of them use apps and websites on their phone, such as SpaceWeatherLive, to track the probability of the northern lights being visible. 

But taking good photos is mostly about patience and preparation, Timmerman said. 

Dahl noted space weather changes quickly. Sometimes, favorable conditions for viewing auroras can disappear within minutes. But, things can also go the other way.

“There were two main blasts last night and I think a lot of people were photographing one,” Timmerman said. “I wasn’t able to get out in time for the earlier lights, but I was able to make it out by 8 p.m. and I think we had to wait almost two hours or so until the next really good lights hit.” 

Being surrounded by other photographers on Grandview Avenue Thursday night made capturing the northern lights a “team effort,” he said. 

“When someone kind of saw they were starting up again, it became like a little cheering section,” Timmerman said. “So everyone kind of knew to get their cameras dialed in and start taking photos.”