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Old 28-05-2018, 08:14 PM
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Stonius (Markus)
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Stonius is offline
Join Date: Mar 2015
Location: Melbourne
Posts: 939
Ah, it's logarithmic! - That makes sense!

So each 30 'gain' is a stop, basically. Each 100 gain is ten times brighter (or dimmer).

The gains I've seen ppl using are 75, 139, 200 and 300.

As near as I can tell, gain 75 would correspond to an e/ADU of about 4.8, which means the entire 20,000 range of the wells are distributed across the 4096 possible ADU values.

139 is 1 e/ADU

If I got this right, then gain 200 corresponds to 1024 ADU levels, or essentially a 10 bit image, and gain 300 is somewhere between 6 and 7 bit with only around 100 ADU levels.

I don't suppose I'm going to break anything if I scale my gain settings in db from 139 for exact bits so there's no rounding weirdness in converting from e to ADU's eg; 139, 169, 199, 229, 259, 289, etc

Best and thanks

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