is cold bad for cameras

[wilson44512]

would it hurt a SLR if it was left in a car. 6 or 7 hours. if it was cold? say about 30F

[erichlund]

No. There are some issues with condensation if you then take it into a warm environment (or is it the other way around???). The real issue is if you are planning to use it right away after sitting in the cold like that. If so, you may want to carry the batteries in a warm pocket. Batteries don't work efficiently when they get cold, so they appear weak. While there may be some temporary power loss from getting cold, most of the power comes back by getting the battery back near regular temp.

By and large, though, the only issues with getting cold are temporary.