One fully charged battery can give you anywhere between 250 to over 1000 shots with the Nikon D200.
Well, according to this thread anyway. Factors influencing this range from whether you shoot compressed NEF vs uncompressed, the type of CF card used, how much LCD review and menu fiddling is done. Read every post in the thread to unearth some fascinating information.
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Nikon D200 Tips & Tricks — Main page