Hi Greg
For DSLR, I originally used a light box from Icer EXFSO and used BYE to get the histogram to around 70% from the left hand side. Worked very well.
Am now using Gerd Neumann light panels, one for the frac and one for the RC8, (I may have over capitalised...) and find I need longer subs but aiming for the mid point on the histogram, again through BYE. Still playing but seems to work ok.
When I grow up and get a ccd then will have to change again. Great fun
I checked in Nebulosity and the flats that work for me give around 20,000 to 25,00 adu
Good thread..