Heavenly Bodies

Astrophotography, nightscapes, low-light landscapes…whatever you want to call them, if there’s a theme that unites them, it’s complexity. When all’s said and done, making pictures like this isn’t simple. It’s reliant on timing, location, effort, the right equipment, and of course a technical mastery built through experience.

Night sky specialist Stefan Liebermann has racked up countless hours under the stars. Location aside, creating images like Stefan’s needs the right technique and gear. The main hurdle is the combination of long exposures needed to expose the night sky and the rotation of the Earth. This causes stars to form light trails instead of appearing sharp as they do to the eye.

“Generally,” explains Stefan, “we use the ‘500 rule’ to work out how long an exposure can be before light trails are visible. This means you divide 500 by the focal length of lens you’re using. So, with the FE 24mm f/1.4 GM I use, the maximum exposure time would be around 20secs. And I’d need to shoot at ISO 3200 or 6400 to get the brightness I want. This is very limiting, so I use a star tracker to extend exposure time.”

For his most recent work, Stefan has been using his trusted α7 III. Setting it up on the star tracker, the camera is slowly rotated to match the spin of the earth, “and this lets me extend the exposure time up to two minutes or longer,” he says. “After taking a separate ‘Earthbound’ exposure for the foreground, it’s then a simple case of combining the two in processing.”

There are other benefits, too. “When you use a star tracker, you don't need to open the aperture so wide either,” he explains, “so you can shoot at f/2.8 or f/3.5, which is really good for sharpness, and use lower ISO settings like 800 or 1000. The tracker also lets me use lenses like the FE 16-35mm f/2.8 GM, where I can be more flexible in framing. When you start using one, you’ll find it’s so addictive, and it takes away many of the super-technical things people have to do with static astro shots, like stacking hundreds of exposures. I just want it to be easy!”

Using his Alpha cameras’ EVFs has also been a great advantage for Stefan when it comes to focusing.

At the end of the day, shooting these kinds of landscapes brings a sense of wonder that every landscape photographer should experience, Stefan believes. “A lot of people spend time reading about it or talking about it,” he tells us, “but they don't get out there and do it! For me it’s the greatest feeling, and there’s extra motivation because it’s often a group activity where I can hike and talk to my friends as we’re making shots. I like to feature them in my scenes, like in this image, because it adds a human dimension, and brings a sense of scale to these huge skies.”

And for Stefan, capturing images like these is important on a wider scale, with light pollution making astrophotography ever more difficult in the populous northern hemisphere. “I think shots like these are a really important record,” he says. “Maybe in 50 years, light pollution and population will have grown so much that we won’t be able to see skies in the same way. It’s so important people know that it looked this beautiful.”