The Picture Show
Astrophotography: Searching Data For Hidden Treasures
Originally published on Wed May 23, 2012 10:30 am
You know those dramatic, colorful outer-space photos you see from NASA? Turns out they're not photographs in the traditional sense; i.e., there's no photographer in an observatory composing the frame with a really good lighting kit. It's all done on the back end — on a computer — and it's a lot of work.
A recent public astrophotography competition, "Hidden Treasures," hosted by the European Southern Observatory (ESO), allowed amateur astronomers to scour its vast astronomical data archives for "cosmo imagery" worthy of the public eye. The challenge was to turn raw telescope images into what we know as "space photos."
The winning images of nebulas, Magellanic Clouds and romantically named celestial objects such as NG3582, are undoubtedly beautiful. The most impressive part of this competition, though, might actually be the explanation of the process of astrophotography processing (here come the nerdy details):
Data produced by telescopes are gray-scale images obtained through colored filters. Processing the images requires the elimination of "unwanted signatures of the instrument" or extraneous data in the image that actually isn't in the sky — it comes from either electricity or the telescope itself. Images are then combined to increase detail or range of view, and finally the images are "colorized" consistently with the filter that used when the image was taken.
"We were completely taken aback both by the quantity and the quality of the images that were submitted," said Lars Lindberg Christensen, Head of ESO's education and Public Outreach Department. "This was not a challenge for the faint-hearted, requiring both an advanced knowledge of data processing and an artistic eye. We are thrilled to have discovered so many talented people."
The winner of the competition, Igor Chekalin, won a trip to Paranal, Chile, where ESO's creatively named "Very Large Telescope" is located.