I am currently shooting in kujjuaq and the temperature this morning was -40.
My setup goes like this:
Alexa mini
Mdr2 w/dm1
Teradek 600
High speeds
Mmb1
I feel like the mini is holding up well. But the HS are really stiff. Thanks to the DM1 motors I am not sure that any arri motor would have work as good in here.
I wrap the camera with an emergency blanket (aluminum on one side and matte green on the other) and I feel like it is helping a lot.
The biggest issue so far is the evf freezing and it seems that hot shots will not help that much. I think that the tvlogic058 is saving us on this one.
My best discovery on this shoot is aluminum tape. It sticks really well and makes everything snug and clean. From now on I will always have aluminium tape with me on cold shots.
Batteries are draining a bit faster than usual but thanks to the new anton bauer xt150 we can shoot 1:30 before having to switch batteries. We are on a documentary style setup so we dont carry any VCLX and the batteries are holding up real nice so far.
Have fun and always keep gloves on your hands no matter what because at this temperature your skin will burn of you touch any metal with your bare hands .