Originally posted by ScooterMaxi Jim Most definitely mount the adapter in the open position and leave it there when using a physical aperture lens. Otherwise, the mechanism will interfere with the aperture.
No no no, ALL versions of the K mount allow the camera to open the aperture. All versions use exactly the same mechanism, where opening the aperture is an active action from the camera, having it closed is the default state. Thus, setting the adapter to open will keep any lens (with an aperture lever, which is almost all of them) open. Set it to closed ("lock") when using the aperture ring on the lens.
Originally posted by baro-nite I've never paid any attention to where the ring is when I mount the lens; if it matters I'll be shocked.
Doesn't matter when you mount it, just close it before expecting the aperture ring to do anything.