I have been looking at older cameras recently and I wondered about battery availability. For example, the Nikon F metered prism heads; can any new button type 1.5V battery be used with it without causing any damage? The original specs for the metered prism head called for two 1.5V batteries. My guess (assumption) is that any 1.5 V battery made today will work provided it fits in the battery chamber. Any thoughts on this?