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Old 04-07-2006, 09:02 AM
Dennis
Dazzled by the Cosmos.

Dennis is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 11,830
Quote:
Originally Posted by g__day
Buying the cables tomorrow and will give it a go in the evening.

One thing that puzzles me is when I start the imager with the lens cap on I get a picture with alot of faint red snow. I expected it to be pretty black, but its like the gain is going overboard. Is that normal for these units?
If you are exposing for several seconds with a non-cooled camera, you will see thermal noise. Assuming the camera is working okay, I reckon that's what you may be seeing?

With my SBIG ST7E ccd camera I expose several "dark frames", to later subtract them from the image, thus removing the noise from the real data. So, a dark frame, exposed for the same duration and at the same temperature of the light frame, will reveal the on-chip thermal noise that is present in every ccd or cmos camera.

Cheers

Dennis
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