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07-19-2010, 07:43 AM   #1
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645 lenses


I have a couple of 645 lenses like the 45-85mm, 75mm, and 55mm. I would like to get rid of them because the adapter to K-mount is too expensive. I would rather upgrade my digital lenses.

I'm not familiar with these older film lenses, but I would like to know when you move the aperture ring from A to 32.......4 2.8 are the blades inside the lens suppose to move.

I know on my FA lenses they move to different openings.


07-19-2010, 07:57 AM   #2
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They are supposed to move when the lenses is not mounted. But when mounted, the aperture will only stop down if you've using the DOF preview button or actually shooting a picture.

This works just like regular Pentax 35mm lenses.

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