Quote:
Originally Posted by gregbradley
Wow, not good.
Did you do flats for each filter or did it constantly shift?
If you had a drifting bias that would make it pretty hard.
I know Richard Crisp made some mention about doing flats for
back thinned chips. Wolfgang said they look weird but they flat out OK
on his FLI. Given their $25,000 + cost you'd want some certainty.
The slow cooling is an annoying Apogee feature. You are not the only one
who did not like that.
Was that the E2V chip?
Greg.
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EV chip. Flats constantly shifted and had to be matched for each exposure.
Lord help you if you actually rotated the camera and didn't have a matching flat. Bias was unpredictable.
It was super sensitive, but you simply couldn't capitalise on it .... I actually pushed SBIG to implement a back illuminated camera but they were fully aware of all the above and politely told me it was a dumb idea
(and in hindsight, they were correct)
BTW SBIG quote 9.3e- read noise on their new ST8300's.
I find it amusing that both QSI and FLI quote 8e- (Kodak's KAF8300 Chip spec) on their implementations of the same chip.... apparently their electronics add *zero* noise to the chip readup.... not likely IMHO
