The test result of power consumption based on Minolta's standard test method is approximately 200 images per set of Ni-MH batteries. DiMAGE 5/7 controls power level strictly as it processes vast amount of data at once, easily affected by even a small factor. For instance, stain on the terminals of battery may change power consumption rate. Please try to wipe the terminals of each battery with a dry cloth strongly before use.
Generally the performance of Ni-MH (Nickel Halide) battery cells may lessen if those are recharged repeatedly without making full use. Please discharge them fully before recharging.