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Old 26-07-2016, 05:33 PM
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Shiraz (Ray)
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Quote:
Originally Posted by Camelopardalis View Post
Dropping the gain from 139 to 50 is just shy of 9dB, so you'd want to increase the exposure length by about 3x to get roughly the same pixel values.

Experimentation is key...my strategy is to expose long enough to get good signal in the object of interest, but not blow out the stars...although there's not always a balance point.
thanks Dunk. the complication is that the read noise also decreases as the gain increases, so you don't need the same pixel values at high gain to overcome the lower read noise.

Agree that experimentation is the best way to sort it out, but this camera is so flexible that there is no single "best" and the suggested optimum at high gains may produce subs that look really crappy - but that still produce as good a stack as that from much better looking longer subs taken at lower gain. ie, you cannot tell by looking at the subs how well you are going - it is only on stacking that the results become clear.

Last edited by Shiraz; 26-07-2016 at 06:22 PM.
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