Outlast - Image #736,430

Hell I have an HD camcorder and can say that this basically exactly how it works.
I've filmed what was practically a documentary in the Grand Canyon with about 10% of battery loss, then turned around to take some Skywalk pictures with the night vision turned on and the battery rocketed down to 14% left (I think it may be because the camera lens tries to distinguish with smaller amount of light available).