I am going on an extended wilderness trip and plan to take a Canon 300D. Battery power is an issue. One consideration is to carry along a gel-pack 12V battery if I could find a 12V automotive type charger for the Canon BP-511 batteries. Is anyone aware of such a charger?

Hahnel do a charger for Canon BP511, that will support 12V charging.

I've used one for a couple of years . I don't think they do the single battery option model anymore it's the twin charging station model that's currently available.

Cheers

John C

You could as well get a small 12v cigarrette lighter plug type inverter connected to a small 2 amp sealed 12v battery and charge directly from that. Bear in mind that the switch from 12v to 110v will have a 25% energy loss or something like that.

I have done extensive trips in the tropical jungle with a 5D with 4 batteries, which is my camera of choice for such an environment. I have a 1DsII, but I feel it is not suitable for that kind of work mainly because of weight and power reasons. It is inefficient energy wise.