Two innovative photographers talk about technology and their Sky Glow quest to capture the majestic movement of stars in the night sky.
After dark, spotting Orion, the Big Dipper and other constellations twinkling overhead can be delightful, but it’s nothing compared to the explosive, spinning and cascading light show that time-lapse photography captures when it tracks the night sky.
Not unlike Carl Sagan or Stephen Hawking, who used science to help bring understanding of the cosmos, Heffernan and Mehmedinović use time-lapse photography to bring new desire for stargazing.
Using particular settings on their cameras, a collection of portable gear and computer technology at home to process their massive numbers of images, the photographers make videos that manipulate time. They create a spiraling Milky Way interrupted only by speeding flashes from shooting stars and trailing meteor streams.
“Ten or fifteen years ago, people like Harun and I could never have achieved this level of output simply because of prohibitive costs and technological limitations,” said Heffernan. “Now, for the most part, the only limitations are the ones we put on ourselves. I think this is a huge reason why you see time-lapse and astrophotography work exploding on the internet right now.”
The two were classmates at the American Film Institute. Capturing mind-bending movements of the night sky has won them spots on National Geographic, weather channels and Daily Planet, but their Sky Glow Project Kickstarter campaign brought their work to new heights.
“Harun and I have built up a great following for our night sky photography and videos,” said Heffernan, pointing to their websites SunchaserPictures.com and Bloodhoney.com. “But we’ve never put our astrophotography into print until now.”
The duo is creating a book of astrophotography accompanied by a timelapse video series exploring North America’s starscapes. In collaboration with the International Dark-Sky Association, the Skyglow Project aims to raise public awareness about the growing threat of light pollution and importance of preserving dark skies.
“Much of what we are photographing may not be around in 50 years, because the dark skies are being impacted by a 6 percent increase of light pollution each year,” explained Mehmedinović in an email.
To create their imagination-stretching videos, the two rely on instinct, strategic planning and the right gear.
“We use five or six cameras at a time, split evenly between Canon 5D Mark IIIs & 6Ds,” said Mehmedinović.
They rely on fast lenses with aperture f2.8 or faster and use remote control intervalometers — which count intervals of time — for each camera.
“We use very sturdy tripods to avoid camera shake and occasionally use Alpine Labs Michron and Radian, which allow for 360-degree turn of the camera while shooting,” he said. They also use time-lapse devices and a motorized dolly for some more advanced moving shots.
“For night astrophotography shots, we set the exposure to 25 seconds and ISO usually around 1600 to about 6400 and always shoot in RAW mode, to maximize quality and keep the color noise down to minimum,” he said.
They spend about four hours shooting a night sky, snapping some 120 images per hour.
“For time-lapses, it’s important not to touch the camera once it’s set up to avoid camera shake, so we just set it all up and walk away, come back three hours later and re-set.”
The next step is taking the images and editing them into video.
A 20-second video clip running at 24 frames per second (FPS) requires 480 still pictures, according to Heffernan. Each photo is captured as a large RAW file, which can play in full resolution on 5K display, which is the equivalent of seven times the number of pixels used to create 1080p HD video. Each photo file is enormous, taking up 27 MB of memory. Multiply 27 MB times 480 photos and total amount of data for a 20-second video is 12.96 GB.
The amount of data for any given project can get tough to track. “I’m not sure what it all adds up to but it’s a lot,” said Heffernan.
To manage these huge files and speed up workflow, Heffernan uses fast Thunderbolt G-RAID 4 TB hard drives to store files and renders them on an Apple Mac Pro powered by a 2.7 GHz twelve-core Intel Xeon E5 processor.
“We’ll do color correction in LightRoom and export another set of 480 JPGs equaling about 10 GB,” said Heffernan. “Those JPGs are turned into 5K, 24 FPS video files using QuickTime. From that 4 GB 5K file, we’ll use keyframes in Final Cut to create 1080p shots with motion.”
He said the trails of light in the video are the moving trajectory of the stars, rendered via a program called Starstax.
“If it’s a big circle with the ‘eye in the sky,’ that means the camera is pointed directly at the North Star. If you see straight lines, that means you’re looking in a different direction.”
The two use their filmmaker backgrounds to infuse storytelling into their time-lapse creations.
“We strive to make each short film cinematic and engaging so our audience can truly appreciate the amazing night sky,” said Heffernan.
Mehmedinović spent his early childhood in Tuzla, Bosnia, where dark skies and nature were pristine.
“I fell in love with the Milky Way and was very fond of fireflies as a small child, which were extremely common there. I have always likened them to stars,” he said. “When I came to the U.S. and kicked around from city to city, it took me a while to realize I couldn’t see the stars at all. It wasn’t until I started doing road trips across the country that I saw them and had a flashback to early childhood.”
His passion for stargazing and photography collided, and soon he was drawn to the Colorado Plateau area, where he met people from the Navajo-Dine and Hopi tribes who taught him about mythology and archeoastronomy.
“Stars are among the strongest natural catalyst for imagination and wonder about the mysteries of life,” he said. “Stars make us feel like we’re part of a much larger universe.”
He’s concerned that light pollution will hide the sky for future generations, and he worries about the harm this will cause to the collective human spirit. The Skyglow Project could kindle a sense of wonder in people who have never seen the majesty of a truly dark sky.
“If more people can experience dark skies, they will fall in love with the sky just as I did as a kid,” said Mehmedinović. “I hope we can get humanity to reverse the light pollution trend.”