Also, 20°F is nothing. The batteries don't have too much trouble with 20 - but getting down near O°F, you will be very surprised at how quickly the batteries disappear! As the others have noted, the thing that does cause annoyance is when the gear has been outside at sub-freezing temps and then you bring it indoors. ESPECIALLY if you go somewhere like a butterfly pavilion, where it's also humid. In that case you can easily have it fog every external surface for a good 15 minutes, and that is precisely the time to have the gear in a plastic bag as it comes up to temperature.
> do they sell chains for the camera's tires?
The closest thing I can think of is a rain cover. If you like being out in the falling snow (or rain), it's a good modest investment.
_____ Brian... a bicoastal Nikonian and Team Member
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