bruce.wilcox
Member
My M3 is off to Sherry Krauter for shutter repairs and I just received a used but very minty Bessa R3a.
My only M-Mount lens is a rigid 50mm Summicron. I notice when this lens is mounted on the R3a that it's just a tad loose - if I grasp both the body and lens and twist gently I can feel a slight movement of the lens relative to the body. The lens mount itself feels firmly attached to the body.
This is a barely-used R3a and an obviously decades-old 'Cron, so I'm not sure whether to think this is slightly sloppy manufacturing on Cosina's part or if the Summicron's mount is worn (though it locks snugly on the M3), or if there's an out-in-out defect. My local dealer doesn't have any Voigtlander lenses for me to test (I just missed a 40mm Nokton for $295!), but I'm tempted to ask if I could mount a new Leica lens for a moment to see how that fits.
Anyway, does anyone else have experience with older lenses on newer Bessa M-mount bodies, and has anyone seen a loose fit?
My only M-Mount lens is a rigid 50mm Summicron. I notice when this lens is mounted on the R3a that it's just a tad loose - if I grasp both the body and lens and twist gently I can feel a slight movement of the lens relative to the body. The lens mount itself feels firmly attached to the body.
This is a barely-used R3a and an obviously decades-old 'Cron, so I'm not sure whether to think this is slightly sloppy manufacturing on Cosina's part or if the Summicron's mount is worn (though it locks snugly on the M3), or if there's an out-in-out defect. My local dealer doesn't have any Voigtlander lenses for me to test (I just missed a 40mm Nokton for $295!), but I'm tempted to ask if I could mount a new Leica lens for a moment to see how that fits.
Anyway, does anyone else have experience with older lenses on newer Bessa M-mount bodies, and has anyone seen a loose fit?
YYV_146
Well-known
My late 70s 50mm Summilux is snug on the R3M, so is a late 80s 90mm Summicron. Don't know about more ancient lenses, though.
swoop
Well-known
Is there a wobble or does it just twist slightly when mounted?
bruce.wilcox
Member
Update: A couple of tiny strips of cut packing tape stuck to the surface of the mount is taking up the slack - no more play in the lens relative to the body.
bruce.wilcox
Member
Just a bit of both (pre-tape).
ruby.monkey
Veteran
For accuracy's sake, shouldn't you have the back of the lens mount in direct contact with the body?
bruce.wilcox
Member
Good point, though I guess it depends whether it's off with the tape in place or without.
Would shooting a distant object with the lens at infinity and wide open with and without the tape be a good test?
YYV_146
Well-known
Testing for both 1m and infinity would probably be safer. And if you are going to test for infinity, it's good practice to use something REALLY far away. The moon would be a good option...if you use a closer object you might be fooled and mess up later shots of further away objects.
Pioneer
Veteran
I suspect you just ran into the Tolerance Bugaboo. The lens tolerance is likely on one end of the scale while your mount tolerance is at the other end.
NicoM
Well-known
I have the same issue with my R2a. My summicron was snug on my Leica cameras, thought it has a little bit of play on the Bessa. Is there a way to adjust the mount to tighten the fit?