coded lens mounts changed

[Fraser]

Just finished changing the lens mounts on my 28 and 90 to coded ones after reading the article on http://lavidaleica.com/content/converting-coded-m-lens-mount
Good advice and very easy much better than the marker pen method also much cheaper than having someone else do it, two lens mounts cost about £25 including postage and I didn't have to send anything away!

 

[Ronald M]

If the lens still will focus properly, you are home free.

Having changed out 6 or 8, I can tell you the original mounts vary in thickness and are probably made that way to accommodate small variations in true focal length. You have to make them match. Micrometer, wet/dry emery, glass plate.

After I fixed mine, they all focus as before. We are talking 1 or 2 thousandths at most.

 

[kbg32]

I was looking to have my pre-aspherical 35 Summilux and 90 Elmar-C coded by Leitz, but they told me that it could not be done because the mount is part of the focusing helical as well. I might see if a local repair service could etch the proper detents in the mount for coding.

 

[Fraser]

If the lens still will focus properly, you are home free.

Having changed out 6 or 8, I can tell you the original mounts vary in thickness and are probably made that way to accommodate small variations in true focal length. You have to make them match. Micrometer, wet/dry emery, glass plate.

After I fixed mine, they all focus as before. We are talking 1 or 2 thousandths at most.

Yes they still focus as they should if anything the 90 seems a bit better😉

 

[Fraser]

Leica surely does not adjust each lens mount to match the lens, when you see the replacement mounts they look every bit as good as the Leica originals.

 

[Pastor Chris]

Leica surely does not adjust each lens mount to match the lens, when you see the replacement mounts they look every bit as good as the Leica originals.

I believe that they do when they code a lens. I have a 50mm Summicron IV that had some focus problems. I took it to Allendale and they put it on their test bench and said that the cheapest way to fix it was to have it coded. They put on a new coded lens flange and adjust so that the focus is perfect, and it is. Obviously the focus problems are going to be more problematic is certain situations, like shooting wide open, but I woe imagine that there is some variation when changing from one lens flange to another. Machining or using a Dremel to code the existing flange seems an easier option. Just my 2 cents.

 

[Fraser]

I believe that they do when they code a lens. I have a 50mm Summicron IV that had some focus problems. I took it to Allendale and they put it on their test bench and said that the cheapest way to fix it was to have it coded. They put on a new coded lens flange and adjust so that the focus is perfect, and it is. Obviously the focus problems are going to be more problematic is certain situations, like shooting wide open, but I woe imagine that there is some variation when changing from one lens flange to another. Machining or using a Dremel to code the existing flange seems an easier option. Just my 2 cents.

Ah right so if the lens has been adjusted after leaving the factory then maybe the mount could have been swapped for a different thickness.