Our camera package was pretty robust considering the size of the crew. There were 3 Canon C300's - A, B, and C cameras. Camera D was our Canon 5d used for stills, timelapse, hyperlapse and our motion control rig. Camera E was our Sony FS700. We used this for ultra-slow motion shots, up to 960 FPS. Cameras W, X, Y and Z were all GoPros, a mix of 3+ & 4's. We also had 2 1x1 LitePanel Astras, a Movi Steadicam Rig, a DJI Phantom 3 Professional Drone, and 4 Lectrosonic Audio Kits. I'd never think that all of this gear would stand up in snow quite as well as they did. I was told not to baby these cameras, and we did not. The first day shooting, the DP had talent throw a shovelfull of snow at his personal camera, the FS700, while I was shooting it. "Right into the lens!" This hazing from Terry also accomplished setting the tone of how we used those cameras. I'd go outside, shoot in -20f, enter our talent's wooden hut, which would be warmed to 70f, wait for the camera to unfog and keep shooting. At the end of the day, I'd clean them up, dry them off and they'd be good to go in the morning.
Despite the durability of these cameras, they weren't perfect. In extreme cold, batteries die quickly. LCD monitors freeze, creating severe ghosting effects in the viewfinder. I struggled to find focus at times. We would use gaff tape and bongo ties to secure foot warmers to our cameras, but it was often useless. The best way to keep batteries was either in a cooler filled with hand and foot warmers, or to keep them under your jacket, against your body for warmth. On the coldest days, GoPros would freeze over in 15 minutes no matter how warm they were kept prior to shooting. They were completely unreliable in extremes, even attached to larger cell phone backup batteries, kept warm in coolers. Wires are also tricky in the cold, they become brittle and snap even when care is taken. I would use an intervelometer on the 5D for timelapse, holding it up to my face as I programmed it. It would freeze in place and seemingly float in the air where I left it. A wire on the C300 monitor snapped and the camera was rendered useless. I was worried about this, but the rest of the crew reassured me that it happens frequently. Overall, considering the extremes we threw at these cameras, they held up quite well.