Originally posted by c.a.m I would have loved to have joined you on that trek. Cape Spear -- one of Canada's greatest locations, IMO. Even in that harsh Newfoundland weather!
"Wind chill" doesn't apply to inanimate objects such as cameras.
- Craig
I'm not sure that is entirely true.
Wind chill, as I understand it, is really a rate of heat loss. That means that a warm object will lose heat faster, but will not get colder than the ambient temperature.
IOW, if an object (with no internal heat source) at 70 degrees (F) is placed in an environment where the ambient temperature is 40 degrees, the object will eventually drop to that temperature. The amount of time this takes is dependent on several factors, including the mass of the object and its surface area. Let's say it takes this particular object 20 minutes to drop from 70 degrees to 40 in still air. If there is a breeze blowing, it will lose heat faster, perhaps in 15 minutes. But it will not go below the 40 degree ambient temperature.
Batteries are chemical devices. All battery technologies that I know of provide less amperage at cooler temperatures than at higher ones. So, the battery in you camera will produce less current and may fail sooner in cold weather than in warm. Wind chill might make it reach that point a little sooner, but it is the actual ambient temperature that is the culprit.
The mechanical parts of your camera, such as the shutter and mirror mechanisms may suffer as well. Again, it is the ambient temperature, rather than the wind chill that is the problem. Parts, especially of different materials, may contract due to the cold, at different rates. Tolerances that are perfectly fine in warm temperatures may suddenly be too tight or too loose, causing binding between moving parts.
Lubricants may harden, as well, restricting the free movement of parts.
All that being said, I think that the battery issues are the most relevant to real life. I've never heard of a camera binding up because of cold, but I have heard of batteries failing due to cold.
Back in the film ear, some cameras, notably the Pentax SF1, had an option of a remote battery. You replaced the in-camera battery with an adapter that had a wire to a battery pack that you could put inside your coat or in a pocket. This kept the battery warm and minimized the current or voltage drop.