Originally posted by 2351HD Hi,
I have been looking at Pentax lens adapters for the K mount and also the Fotodiox RhinoCam adapter.
These systems allow use of A and FA lenses to be mounted.
My main question is this: if I take a look at my 35A and 150FA, the have an aperture ring, but also an aperture lever on the rear of the lens. You can turn the ring, but the lens does not stop down until the lever is turned.
So...do the lens adapters for K mount and the RhinoCam adapters turn the lens aperture lever when you attach the lens to the mount? Is that how it works.
If somebody with experience with these sorts of adapters could comment it would be great.
Thanks
The aperture function is essentially the same in all the lenses be it PK, 645 or 67. The lever is how the camera stops the lens down during exposure or DOF preview, while the ring is what determines its travel, e.g. which f-stop determined by which detent you set the ring at. You can see this off-camera like you were looking by selecting a wide open aperture on the ring, then moving the lever - the lens won't stop down because you're set to wide open. Now select a much higher f-stop then move the lever - the lens will stop to whichever setting you've selected.
All the adapters really do is provide a correct distance to the focal plane, a proper mounting lock for the lens mount type, and allow the "different" camera type to interact with that lever.
Short answer = "yes."