Thursday, August 17, 2017

Solar Eclipse Photography Is About Trial and Error, Says This Astro-Pro

Solar Eclipse Photography Is About Trial and Error, Says This Astro-Pro:

Solar Eclipse Photography Is About Trial and Error, Says This Astro-Pro
The progression of the 2015 total solar eclipse, imaged from Svalbard, Norway, by astrophotographer Kevin Morefield.
Credit: Kevin Morefield


When Kevin Morefield was young, he wanted to be a sports or nature photographer.

"I wanted to work for Sports Illustrated or National Geographic," he told Space.com. "But only like, 20 people in the world have those jobs, so I got into finance instead."

That day job allowed him to pursue astrophotography as a hobby. Now retired, his photographs have appeared in magazines like Sky and Telescope and the Atlantic, and have won him multiple "Image of the Day" awards from various online outlets. His Instagram feed shows some of his work on deep-sky objects (nebulae, galaxies and the like), planets and eclipse shots. [Total Solar Eclipse 2017: When, Where and How to See It (Safely)]

Morefield said learning to get good shots of an eclipse involves a certain amount of trial and error. During one eclipse, he taped solar filters to his camera lens for the partial eclipse and then pulled them off at the start of totality (when the moon fully covers the disk of the sun).

Kevin Morefield learned how to photograph astronomical objects in his spare time, through lots of trial and error. Morefield pictures here with an automated telescope, which he can operate with his phone or PC, that he uses to capture night-sky images
Credit: Kevin Morefield


"When it came time to take the filters off, I pulled [the camera] out of focus," he said. Morefield had set up an automated system to snap photos during totality, so he didn’t look through the lens and didn't realize his mistake until it was too late. The images were lost, but Morefield said he also had a video camera running. [Best Gear for Taking Photos of the Solar Eclipse]

"I thought I had it on video and I ran back the tape — in 2010, HD digital video still shot on tape — and I saw I had it," he said. "Then the mayor wants to come up and talk and I took video of that and I [later] found I'd taped over it."

One tip Morefield offers for people photographing eclipses: Make sure the camera is in focus during the partial phases. Shoot through a solar filter — otherwise the sunlight will just wash out the picture (and potentially damage your equipment and eyes) — and focus on the edges of the sun. He added that making sure the exposure time is set appropriately is also key, because catching the relatively dim corona (the sun's outer atmosphere) during totality will require different settings than a filtered shot of the partial phase. Lastly, a tracking mount — one that follows the sun across the sky — is essential for close-in shots of the sun.

A two panel mosaic of the Orion Nebula (M42) on the right and the Running Man Nebula (sh2-279) on the left, taken by astrophotographer Kevin Morefield. The image required a total of 18 hours of exposures.
Credit: Kevin Morefield


Automation is also helpful, Morefield said. He currently uses a Canon 6D and generally shoots pictures at an ISO, or "film speed," of 400. The camera also allows for pre-programming sequences of shots with varying exposure times and apertures (not every model of digital SLR has that feature).  [How to Film or Photograph the 2017 Solar Eclipse Like a Pro]

When watching an eclipse — especially a total solar eclipse — most experts recommend focusing on what's happening in the sky rather than fiddling with a camera. On his earlier eclipse shoots, Morefield used a remote shutter release and a tracking mount for that reason.

"[Photography] is not distracting, but I automate a lot," he said. There are even programs that one can download specifically for eclipse photography, such as Eclipse Orchestrator. (For his part, Morefield will be running a program that takes hundreds of images.)

At the same time, Morefield said it's important to think through what you want to accomplish with an eclipse photograph. While it's possible to take close-ups of the sun to capture the corona or other eclipse-related phenomena, it's also not a bad idea to use a wide-angle lens to capture what's happening around you. [The Best 2017 Solar Eclipse Live Video Streams ]

"You might try to get what's going on with people and the sky and the ground," Morefield said. "Like, the diffraction pattern you see on the ground that lasts 3 or 4 seconds. With a superwide angle, you're more likely to see the shadow bands. Or, one could look for projected images of the eclipse made by ordinary objects. A straw hat or leafy tree, for instance, produces dozens of tiny, projected images that can create interesting shots."

When photographing cosmic events, should sometimes it's good to focus on the ground as well as the sky, said astrophotographer Kevin Morefield. Shown here, a shot by Morefield of the northern lights over Svalbard, Norway, in 2015, and a crowd of skywatchers viewing the light show.
Credit: Kevin Morefield


Morefield outlined how he will be taking his pictures during the Aug. 21 total solar eclipse. His program, he said, starts about a minute before first contact (when the moon begins to overlap the sun). About half of the pictures will be taken during totality, which will last for just over 2.5 minutes in his viewing location. The exposure times will range from 1/1600 of a second to 2 seconds.

Before he takes off the solar filter, he will check the camera's focus. Before totality, Morefield says he typically uses a 1/1600 speed and f/8 aperture setting. He pulls off his solar filter when the "Baily's beads" and "diamond ring" effects appear: these are the last spots of light visible on the edge of the moon before the sun's disk is fully hidden.

During the diamond ring phase, Morefield said the corona begins to become visible. He said he uses "bracketed exposure" while imaging the diamond ring, which means taking several pictures at different shutter speeds.

"I'll use a combination of three or so exposures in the diamond ring phase, with exposures also at 1/25 to 1/800," he said. For "Baily's beads, he uses1/4000 to 1/8000" exposure times.

His first exposures of totality will be short, and they will get longer with each shot.

A "diamond ring," which occurs seconds before or after totality during a total solar eclipse, captured by Kevin Morefield.
Credit: Kevin Morefield


Morefield's adventures with eclipse photography started in 2002, but his interest was piqued before that. He grew up looking at the sky through his home telescope and saw a partial solar eclipse over his home in the 1970s. Amazed by pictures of total solar eclipses, seeing one in person became like a "holy grail." He finally planned a trip with his father to see the total solar eclipse over Australia in 2002.

"We had to fly 24 hours to get to Adelaide to drive on the wrong side of the road," Morefield said of the trip. "When we got there, it was with a group of like 1,500 other people … from all over the world."

Seeing a total solar eclipse with such an international group was "a little bit like the Olympics, where people put aside all their differences," Morefield said. "Totality was 27 seconds long and the minute it was over, everybody's like, 'It was worth it.' It's really an emotional experience."

Follow Jesse Emspak on Twitter @Mad_Science_Guy. Follow us @Spacedotcom. We're also on Facebook & Google+. Original story on Space.com

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