Weird Marking on Inside of Rigid Summicron

[DanielJohannes]

Hi everyone,

Noticed something pretty weird today. After unscrewing the head from my 1963 summicron for cleaning, I saw some strange markings on the black ring that holds the rear elements. They appear to say "17 m". Some are also visible when looking down the rear of the lens, that seem to say "19N" or "19M", though they are far less distinct. Weirdly, I can't decide whether this is something deliberate or the result of accidental damage.

It seems to me that this could be A. wear from normal use (ie. sand getting inside the focusing mechanism), B. the workings of an irresponsible owner, C. the workings of an irresponsible technician, D. something that was done in the original factory (though this seems unlikely).

I don't have much information about the lens or its previous owner - it came from ebay about 2 months back, and is otherwise in mint condition. If this is the result of normal use, does anyone have any advice on how to prevent it happening again in the future? If it is a deliberate marking, has anyone seen anything similar? Any thoughts on what their purpose might be?

Here is a link to some pictures: https://www.flickr.com/photos/158657265@N07/with/27998316509/

 

[x-ray]

Leica marks the mounts and heads in the factory indicating matching units. Each lens unit is measured in focal length and marked as the mount fabricated and adjusted to give optimum focus for a given lens unit. It's possible to swap lens heads between various 50's for example but focus would be off if the mount isn't optimized for the head.

Every Leica lens I've owned for the past fifty years that has a removable head has similar markings. Components are matched for optimum performance.



Don't worry about it.

 

[DanielJohannes]

Wow, that's very interesting. I wonder why this was done by hand rather than machine engraved.

What do you make of the numbers not matching? Is this to be expected, or might the mount have been switched at some point?

I hope these questions aren't too obvious - this is my first Leica lol.

 

[x-ray]

These lenses are made by hand and the numbers would be hidden from sight. Why go to the expense of machine engraving something not intended to be seen. Usually the number on the head and mount corresponds to the last part of the focal length like 50.19mm. It's the last digits to the 1/100 of a mm.

If the mount numbers don't match the head it's possible another mount was swapped with the original. If that occurred it's possible that Leica recalibrate the set or if not it could either be a tiny bit off focus or close enough where you'd never see the effect.

If it focuses properly and is sharp wide open I'd not worry.

 

[Erik van Straten]

Mine (214XXXX) reads: 74 19N. As others have said, in almost any old Leica lens you will find markings like this, even in the oldest Elmars.

Erik.

 

[Rluckettt]

I would guess that if your aperture index dot faces up and aligns with the focus index as it should, that the lens has been serviced and should work fine. Is it sharp at the infinity lock?

 

[giganova]

Wow, that's a good looking and clean Rigid! Wonderful to see the markings on this hand-made lens ... I should check mine. Can I simply unscrew the black collar?

 

[jonmanjiro]

Very common. Every Nikon RF lens I've opened has had similar engravings.