What should you pay attention to when shooting with Canon SLR cameras in ultra-low temperature environments?

I am from Harbin and a 60d user. Harbin is much colder than Beijing in winter, but we still shoot the ice lanterns and the ice and snow world at night. The temperature is minus 40°C at the coldest time, and the lens occasionally zooms. Sometimes it's so cold that it can't be turned, but it'll be fine once it gets better. The battery consumes very quickly at low temperatures, so just prepare a spare one. . . Let me tell you a few of my experiences. First, after taking the photo, take out the memory card and put it in your underwear pocket when you go back. You can enjoy and process the photos when you get back. But put the camera in the camera bag and don’t open it after entering the house. The next day Turn it on again and let the machine adapt to the temperature changes naturally. It's absolutely fine. Instead, you can hold the machine in your arms and wrap it with a coat (down jacket) between shots. In fact, the main purpose is to prevent the machine from suddenly entering a warm room from a cold outdoor and causing frost. . . . .