Using the register shutdown option I just compared the deep sleep battery current on the 3 cameras, sketch takes a picture and goes into deep sleep;
No register shutdown OV2640 22.3mA
No register shutdown OV3360 37.8mA
No register shutdown OV5640 104mA
With register shutdown OV2640 22.3mA
With register shutdown OV3360 1.45mA
With register shutdown OV5640 1.4mA