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Terry,
The camera (Opticstar 145m) has a Sony EX HAD chip in it the ICX285AL to be specific, this does not have a published well depth that I can find but estimates are in the 27,000 to 30,000 range.
So I want 30,000 electrons to give me 65,000 levels - sounds like my gain should be set to 2, or is it not tahat simple?
I do not get why this advice would work :-
'Then take exposures of anything bright trying to completely saturate the CCD with any exposure time. The gain then needs to be adjusted to so that the totally saturated exposures read about 65000. Keep reducing the gain until you start to get readings just below this value."
Surely the exposure time is relevant? Say I expose for 5s and 1s and both images have saturated the target then I choose to set the gain based on the 5s exposure I may have to wind it to zero to get max values less than 65000 whereas the 1s exposure may need the gain at 10 to get max vals of 65000.
Oh well I am going to try a run of images with low gain and see if it is better or worse than my normal setting...for now I am confused.
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