Photographers rely on light, which creates a peculiar set of problems when shooting in the dark
For Astrophotographers, Whose subjects are thousands of light years distant, picture taking becomes a momentous technical challenge. To capture the photographs reproduced in the Shooting Stars feature, John Doogan enlisted astronomer Fraser Gunn to help scout locations and provide some specialist equipment rarely required when shooting in daylight—telescopes, tracking mechanisms, even lens heaters to prevent condensation developing on the outer elements during long exposures.
The pair waited on the weather, on clear skies, on phases of celestial bodies, they set up tents beside remote tarns, huddled from the wind in rock crevices beneath mountain tops and shivered on icy mornings. Sometimes they had to contend with the unexpected—such as when the army sent up a barrage of flares from behind Lake Alexandrina in the middle of an exposure.
Sometimes the photographs revealed detail invisible to the naked eye; a faint glow of an aurora australis is present in a picture of the Sierra Range that couldn’t be seen for the profound darkness, wind and cold on the top of Mount Olivier.
To render this depth of detail, most of the images were not single exposures but multiple frames set with an intervalometer and stacked together to record the movement of stars through time, or shot as the camera panned through 360 degrees, then stitched together digitally as one might create a patchwork quilt—the whole being so much greater than the sum of the parts.
The picture above involved both stitching and stacking to create a field of view impossible with a regular lens, and enough depth of field to accommodate the foreground figures and stars thousands of light years away. Gunn holds a night-vision lamp; another torch (reduced in brightness with a cover to balance the light sources) lights the tent from the interior. The Milky Way just does its thing.
All of the photographs benefited from the phenomenal sensitivity, low noise and robust colour quality of modern digital sensors. Indeed, these photographs may not have been technically possible just five years ago.