Makes sense. I do recall my D200 went through the batteries. My D7000 has way better battery performance.

See if you can find a battery grip for it - that should solve the issue.

IIRC, there are a couple of different noise reduction settings. One for high ISO, one for long exposure. Make sure they're both off. That's the most likely cause of the necessity to have more...

I never tried exposures that long on my D200. I think the longest I did was around 15-20 seconds. What I found was the sensor would heat up, giving lots of red around the edges of the image.
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