Night Time Battery Usage

I plan to buy the BG-E3 Battery Grip for the XT.
But I'll only use one battery for now, is that enough for night time bulb pics?

Does long exposures eat more battery than usual?

I was concerned about battery usage when I went to photograph the Perseids meteor shower last week. I have a 350D but no grip so I was limited to what I could get from one battery.

But I had no problems. I shot around 75 long exposures with a cumulative exposure time of over 2½ hours and the battery still had plenty of charge left in it. (Perhaps one benefit was that I wasn't using the autofocus or the LCD for chimping/review.)

I always carry a spare, fully charged battery where ever I go. They are cheap and you won't miss a shot.
I've have the XT and find that the battery life is great. Gone a full day shooting without a problem, even shot one night for 3 hours at -20C and still had life left, fingers were frozen but battery was still functioning.

Wayne

Only worry if you don't have spares. Go to Sterlingtek and get 2 spares for about $20 and you'll be good. I don't ever need to put the spare in with my 5D, but I have spares and the 20D does have a grip, but even then, not that big a deal. A charged battery should take 300-500 shots without a problem.

I have spares. But if the camera is attached to a tripod taking a very long exposure sequence, you can't change the battery without disturbing it.

I shoot deep sky objects with my 20D and telescopes, exposures range between 3 and five minutes. During the warm months the batteries hold up very well, during winter not so well. I can shoot from sundown to dawn on two batteries in the spring/summer/fall, but in winter I go through over three fully-charged batteries. I use the LCD frequently so that adds to power drain.

NH