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Old Jun 3, 2010, 10:38 AM   #11
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Cliffyk, I have had my A550 for several days now and have tried most of my Minolta lenses for fit and have not found any that do what you have described. Manufacturing being what it is normally lends itself to uniform results. As TCav suggested I would look for damage to the lens and unless something is obviously out of shape I would deburr the mount and make sure there was a uniform and clean shape to the leading edges.

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Old Sep 26, 2010, 10:38 PM   #12
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Originally Posted by Old Boat Guy View Post
Cliffyk, I have had my A550 for several days now and have tried most of my Minolta lenses for fit and have not found any that do what you have described. Manufacturing being what it is normally lends itself to uniform results. As TCav suggested I would look for damage to the lens and unless something is obviously out of shape I would deburr the mount and make sure there was a uniform and clean shape to the leading edges.

Good luck

Steve
For the last time (guaranteed) there is nothing "wrong" with the older metal flange lenses, it is simply that they were finished machined for a different environment; one in which they were mated to a hardened stainless steel receiver. The interference to which I speak is a subtle issue, which to me has become obvious to be too subtle for many/most to observe, be that as it may it is nonetheless there.

All that aside. what has struck me most about this experience has been the immediate, nearly vitriolic and confrontational dismissal, and subsequent discount of input from a "newbie".

The interference described is product of the contour of the loaded/leading edge of the older lens's metal tabbed flange being inappropriate for mating with the plastic receiver on the newer camera bodies.

This is a blatantly obvious mechanical issue, and should the resident "gurus" take time to examine the respective sections of the contemporary plastic flanged lenses, vs. their metal flanged predecessors, it would be obvious even to their closed minds that the newer lenses have a chamfered and "softer" loaded leading edge than did the metal flange lenses--which as stated above mated with a hardened stainless steel receiver on the body--with the lens flange acknowledged as the wearable/replaceable "many" of the "one to many" body to lens relationship.

This (the softened/chamfered leading edge on the plastic flanged lenses) is an engineered response to the characteristics of the materials chosen for the newer mount.

I have relieved the leading edges of the metal flanges of the four older lenses in my possession as described in my first post, and as a result am quite satisfied with the manner in which they mate to the a230. My wife repeatedly says I am "picky", and I suspect the interference to which I protest is likely "picky" and far too subtle for most to notice.

And also I once again apologise for invading your clique and causing so much upset; it was certainly not my intent...
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Old Sep 27, 2010, 7:18 AM   #13
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Since your first experience with a metal lens mount, have you found any other lenses with metal mounts that did the same thing?
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Old Sep 27, 2010, 11:59 AM   #14
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How many of the contemporary lens makers use a plastic mount? The only Minolta lens in plastic I had laying around was a 35-70 that came as a kit lens with a bottom of the line camera.

I understand what you are saying but the lack of reported issues does not indicate there is a problem. Unless the lens mount has sustained damage.

Looking closely at my A550 I notice that the plastic ring inside the camera appears (I am not taking it apart to verify) to have a slight taper. Both the Minolta 50mm f/1.7 (25 years old) and the Tamron 17-50 f/2.8 (less than a year old) when placed into the mount and turned just slightly will still wiggle but will not lift straight off of the body. So the lens is captured within the mount but there has been no friction on the leading edges of anything. On my camera (your mileage may very) as I rotate the lens to the locking position I am half way through the short arc before I feel "friction" and that puts the metal of the leading edge of the lens mount against the wave spring which is where it should be.

From an engineering standpoint the plastic inner guide ring (when properly manufactured for size, shape, and material) would have a reduced drag coefficient over a metal counterpart when using metal mount lenses.

What you see as "a Blatantly obvious mechanical issue" I see as a potential improvement (when properly executed of course).

If we forget all of the speculation and eyeball engineering in favor of the only hard data available "reported issues from the field" your theory is unsupported. I spent quite a bit of time here and other places reading reviews, both professional and user based, and I cannot remember one where someone mentioned a chewed up mounting ring inside a camera.

Steve

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