Quote Originally Posted by wiltw View Post
But they are 1.5v and decline voltage over their lifetime, whereas CdS meters RELY upon a constant and unvarying 1.35v provided by mercuric oxide batteries. Simple substitution of alkaline or silver oxide very frequently results in inaccurate readings that cannot be simply compensated with lying about ISO...the Olympus OM-1 is one such example.
I must respectfully differ. Silver oxide cells are very consistent over their lifetime, whereas alkaline cells are not.

One cannot just substitute the silver oxide cells for the mercuric oxide cells, because the meter circuit's response to the incorrect voltage does not necessarily result in a linear error. If one reduces that voltage appropriately however (through an appropriate adapter or other circuitry)the meter circuit will respond appropriately.