Good to know, I will limit myself to 20 x say 2 min subs, at ISO 800....with corresponding darks and sooner rather than later, some flats.
Might have to go digging up on how to take the proper flats with the T shirt method, I vaguely recall something about 2/3 of the histogram and fastest shutter speed, or is that bias?
Thanks for your help Bojan
Cheers
Chris