Gee Alex you want to get it a little colder then that as there is a big difference between -10 and - 20 degrees C (told you they were quiet
). Last night was about 30 odd degrees and the camera was sitting on -20 at about 77 - 80%. best you find a temp that it can consistently achieve so your darks library does not need to be too big. Finally built mine out to 30 mins but I doubt I will need subs this long for anything much. Congrats on the new toy and I wish you luck with the OAG as I have pretty much thrown my hands into the air ( once again) and reverted to a guide scope (much easier).
Mark