Still discussing about batteries? You guys realise most of our cameras use bridge circuits that are unaffected by voltage? For instance, my Praktica MTL50 does take at PX28, but when it arrived I didn't have the battery, so I used a stack of LR44s to test it. Little particular: I needed to fit FIVE batteries instead of four!
However the reading of the lightmeter was perfect and I could use the camera without problems.
Cuthbert,
I'm sorry but i'll have to disagree with you, despite mostly agreeing on everything.
Not all cameras have such "compensated" circuits. The question I addressed was related to the Nikkormat, and the Nikkormat uses a very very similar circuit to the one on the Photomics for the Nikon F. And such circuit is very, very sensitive to battery voltage (been there, have tried recalibrating that circuit, had to adapt zinc-air batteries at the end).
As for your Praktica MTL50, that's a 1985 camera, not fair!! By that time practically all cameras had regulator circuits inside. Also, it takes a PX28 battery, and I dare to say that all cameras that use the PX28 have a voltage regulator circuit, since most of them (i.e. Canon A-series, Pentax 67, Mamiya M645) are known to work fine with alkalines; in some cases the manual itself tells you to use an "alkaline or silver-oxide battery".
BTW, to assemble an ersatz PX28 battery, just buy an old PX28 and use the front and rear metal "caps" to make the four LR44 cells achieve the same height as the original. Wrap in some masking tape, and you're good to go. This is done frequently in my city, where a PX28 battery is more expensive than buying four LR44s.
And it allows you to assemble a silver-oxide PX28 if you want! (by using SR44s). Longer life.