Originally posted by LowVoltage Ok folks, please kindly clarify my thinking on this:
...I'm just worrying about this for nothing, right?
Right.
Quote: I read about the Ricoh lenses with the pin that needs to be removed from time to time, but that's on a lens mount meant to mimic the K-mount, obviously not the screw type. Nevertheless, this is the kind of thing that makes me nuts; I'm a worry wart.
Stop worrying. A KR-mount lens, with an A(P) position on the aperture, MAY have the dreaded Ricoh pin, or maybe just a harmless nub. M42 screwmount pins are NOT a hazard.
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A note on M42's -- Three sorts exist:
1) No aperture automation -- one aperture ring, or two rings (preset). These are simple to use: Set the aperture and shoot. With a two-ring preset lens: Set the desired aperture, spin the loose ring up to compose, then spin it down to shoot.
2) Aperture automation with a M/A (manual/auto) switch. Set the switch to M and they function just like type (1). Set the switch to A, and you get aperture automation ON FILM BODIES THAT SUPPORT IT, but on dSLRs they stay wide open.
3) Auto-only, no M/A switch. On dSLRs they stay wide open, unless the pin is jammed or glued down, which can reduce the value of the lens. Avoid auto-only M42's unless you're a film-shooter, collector, or lens doctor -- or you like shooting wide open.