Calculating Well Depth

Anything that doesn't fit into any of the other forums
Post Reply
User avatar
oopfan
Posts: 1321
Joined: Sat Jul 08, 2017 2:37 pm
Location: New York
Contact:

Calculating Well Depth

#1

Post by oopfan »

Robin,

I learned about a method by Berry and Burnell for calculating gain (e-/ADU) from two raw bias frames and two raw flat frames.

Could you share the method for calculating Well Depth?

I want to use a gain setting in between two settings in the Sensor Analysis. I'd like to know what the value is without performing linear interpolation.

Thanks,
Brian
User avatar
admin
Site Admin
Posts: 13177
Joined: Sat Feb 11, 2017 3:52 pm
Location: Vale of the White Horse, UK
Contact:

Re: Calculating Well Depth

#2

Post by admin »

Hi,

full well depth is given by

(max ADU - black level ADU) * e per ADU

This assumed linear response for the whole range of the camera, which as you know isn't strictly accurate, but is good enough.

SharpCap uses linear interpolation, but does it on the relative gain rather than the e/ADU, since the relative gain graph is less sharply curved (and the one is just proportional to the reciprocal of the other). Similarly, the read noise has a good relationship with the e/ADU value, so SharpCap interpolates the read noise against e/ADU values rather than camera gain values - it gives a much smaller error that way.

cheers,

Robin
Post Reply