ADU values for flats

[alanrock]

I apologize if this isn't the right place to ask this question, but, here it is:
How close do the ADU values need to be in my flats? If my flats are all in the range of say 19-21k, is that close enough?
Thanks in advance!

[pfile]

if your sensor is linear in that range it should be fine. the idea is to get the brightest flat sub possible while still operating in the linear response portion of your sensor.

rob