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How to use bias frames?
After several years of pre-processing with Nebulosity I have now tried to use bias frames.
I want to apply them to 10 minute lights taken with a QHY8l at gain zero.
So I tried 20 bias frames of 0.001, 0.01, 0.1 and 1 seconds.
Each set stacked and used in four preprocessing runs of Nebulosity
(darks and lights both 600 seconds).
The result is a hideous mess,black background, no detail and prominent hot pixels.
Google has any number of entries on how to take bias frames but I could not find any on how to use them.
To ask a beginners question, I am obviously missing something. What?
Chris
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