I have a CCD sensor datasheet which cites the following parameters in accordance with the EMVA 1288 standard:
ADC bits 14 bits
Well depth 17273 e-
Gain (e-/ADU) 0.17
I'm unable to reconcile these numbers. Shouldn't the gain just be the ratio of the number of electrons in the well to the ADU pixel counts? In that case, shouldn't it be equal to 17273/2^14 = 1.054? Or am I missing some kind of nonlinear behavior close the full well depth which prevents one from calculating this ratio at full well capacity?
In case you are curious, this is the Grasshopper3 GS3-U3-14S5M-C camera from PTGrey. The datasheet is available on their website.
Interestingly enough, when I look at the specs for a different ST-8E camera: FWC=180000, ADC 16bit, the datasheet value of gain=2.8e-/ADU is quite close to the ratio FWC/2^16=2.74.