No David one relatively short session. The Canon 5DH is modded that is what the H stands for, ie Hutech modded. The cooling is active so it lasts as long as you want and fully controllable. Just search my posts and you will find more information.
Here is a thread to a single exposure at 1600 ISO at -10C. It also gives more information.
http://www.iceinspace.com.au/forum/s...ad.php?t=29434
Bert