I recently purchased a used 75mm f4.5 Nikkor lens on a famous auction site. The glass is in fine condition, but the aperture diaphragm, although round enough, is about a millimeter off-center. When the aperture is opened, a 1mm crescent of visible blade remains around half of the periphery.
What is the optical effect, if any, of a slightly off-axis aperture? Should I return the lens, or just blithely use it to make my usual bad photographs?
-- Jay
How many aperture blades in the shutter?
How many of them are not opening fully?
- Leigh
It's a standard seven blade Copal 0 shutter. All the blades open fully, but the entire aperture assembly is not centered on the optical axis of the lens.Originally Posted by Leigh
Agree, one or two may have jumped the pins. Putting in a too-long index screw can touch the blades and cause one to jump out of place.
Jay, there are certain lenses, antiques like Verito etc. that I would have a wide tolerance for that condition and others like a modern wide angle where I would have zero. I'd return it.
Gentlemen, thank you very much.
-- Jay
I just realized I have that exact same lens (Nikkor-SW).
Upon examination I find that the aperture blades are absolutely uniform from full open to minimum.
- Leigh
Thanks, Leigh; that's helpful information.
-- Jay
Same on mine just as it should be, and Jim has absolutly right on this one as almost ever!
Cheers Armin
Posting Permissions
Reply With Quote
Bookmarks