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April 17, 2007
1:00 UTC (approx)

Nikon D200 on CDK20 at Moore Observatory
30 second exposure

85mm f/1.4 lens (stopped to f/2) ISO 400. It's a 30 second exposure,
tracking with the CDK20, in noise reduction (dark subtraction) mode. I've
scaled the original 10 megapixel image down by a half in each dimension here, so
it would be about 2.5 MB uncompressed. The compressed file is 1 MB.

Lyra is in the upper right quadrant with north up, west to the right. The
faintest stars in the original are about magnitude 10.5, but it's not quite in
focus so that will go fainter when it's optimized. 7th magnitude is about
halfway down the dynamic range from full bright to the sky background. Except
for rotating the image and scaling down, its unaltered from the file out of the
camera. The camera software did the compression to 8-bit depth.