David Stephenson used multiple techniques to photograph the night sky in his series Star Drawings. The lines and shapes created by the earth's rotation make for interesting views of the stars and dark sky above.
His technique is a blend of interval exposures and multiple long exposures giving each of the photographs in his series a unique look. Stephenson says he is drawn to the awesome vastness of time and space, referring to his practice as a search for a photographic sublime.
David Stephenson lives and works in Hobart, Tasmania. He is Associate Professor of Art at the University of Tasmania, where he serves as School Research Coordinator and Head of Photography at the Tasmanian School of Art. He is Co-director of the University's Arts and Environment Research group.
See more of David Stephenson's work at davidstephensonart.com
Here is a write up on how to duplicate this look / image. It includes a photoshop action. http://blog.starcircleacademy.com/2011/02/automated-stacking-of-star-tra...
It's time-lapse star trails + blending multiple exposures. Here's my video on how to make star trails: http://www.youtube.com/watch?v=V6ypRbPzoPM
For some of the pictures, he's flipping them horizontally and then blending them together (probably as additive layers in Photoshop). I'm not sure how he gets the spiral effect, though.
I really like the last three shots. They're a unique take on star trails.