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Even worse is some quite strange behaviour by either the 16803 chip or the way Apogee handles it. Each frame seems to have a dozen or so quite faint quasi-stellar bright spots. Not after-images (residual or ghost), not hot pixels, but something with an FWHM of about 2.5 pixels. But they are random. In the next shot, they will be somewhere else. I try to find them by automatically searching for spots that are only in one channel, and zapping them. New darks can only help, of course.
Those would be cosmic ray hits which often look like a streak or a wormy streak.
These disappear with median combine as they are random as long as you have enough subs to make them clear as outliers.
Greg.
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