[Autonerd]

Thought I read somewhere on these forums that (at least some) Spotmatics work correctly with modern batteries. The clip-on meter (the square type) that came with my SV works accurately with a silver oxide battery. It must have internal voltage regulation.

Doing some research, I read that as well -- the meters will correct for the higher voltage of a newer battery.

Aaron

[tonyzoc]

Tony

Can't use the button to do stop-down metering because the lens has no pins! The camera has no way to manipulate the aperture. The lens has nothing by way of contacts - it just has the m42 mount. When then lens is mounted, the Spotmatic's meter will always register as over exposed (I have another post about this: Handling a Beast 400mm f5.6 on Spotmatic F - PentaxForums.com). If you stop-down the lens, the meter still always reads as over-exposed. In any case, the Spotmatic F is a keeper!

This is wrong. The stopped down lever on the left side of the body is specifically using lenses without pins in a stopped down metering mode. It's there to provide support for Super Takumar, Auto Takumar and Takumar lenses, none of which have aperture set pins. See pages 20-21 of the user manual which can be downloaded here...
https://www.butkus.org/chinon/pentax/pentax_spotmatic_f/pentax_spotmatic_f.htm

[petermorris]

THANK YOU, THANK YOU Tony! I just verified that I can meter with the switch up! I'm sitting around here hoping that the clouds will clear for the aurora borealis, but it looks doubtful. But you have brightened my evening... my misconception was that this switch acted like pushing the timer switch towards the lens on an MX. But this is a different function indeed. Thanks for the digging!