Well, dynamic range is usually thought of in terms of f stops. For example, the ASI1600 has a maximum dynamic range of about 12.5 stops at zero gain. You can find this on the chart they provide down this page on their website:

https://astronomy-im...-3-0/asi1600mm/

I'm not sure what the units are for the 2564 number you calculated, or how you would apply it in practice.

-Dan

Dynamic range is usually expressed in either decibels or stops. You can calculate the dynamic range in decibels with this formula:

DRdb = 20 * log(FWC/RN)

You can convert that to stops with this formula:

DRstops = DRdb / 6

Dynamic range in "discrete steps" is simply:

DRsteps = FWC/RN

So, if you have an FWC of 4095, and read noise of 1.55e-, your dynamic range would be:

DRdb = 20 * log(4095/1.55) = 20 * log(2641.94) = 20 * 3.422 = 68.44dB

And converting to stops, you would have:

DRstops = 68.44 / 6 = 11.4 stops

For the record, stops and bits, effectively the same thing for all intents and purposes. You can recover bits with stacking, though. You would then divide the read noise by the square root of the number of subs stacked to determine how much bit-recovery potential you have:

BitsStacked = (20 * log(FWC/(RN/SQRT(Subs)))) / 6

So if you have an FWC of 8192, read noise of 2e- and you stack 64 subs:

BitsStacked = (20 * log(8192/(2/SQRT(64)))) / 6 = (20 * log(8192/0.25)) / 6 = (20 * log(32768)) / 6 = (20 * 4.516) / 6 = 90.31 / 6 = 15.05 bits

(NOTE: Technically speaking, dynamic range in stops/bits is also dependent on camera noise from other sources like dark current, glows, etc. And if you want to be truly accurate, the skyfog offset is also going to limit your dynamic range. So the above would be the maximum potential bit depth of a stack if you only had object shot noise and read noise.)

**Edited by Jon Rista, 05 January 2017 - 08:44 PM.**