Our client and friend Laurent managed to install the Contax-Nikon mount on the Vario-Sonnar 3,3-4,0/28-85mm.
Also he is sharing the particularities of this lens conversion (it will work for Pentax and Sony too):

Hello,
I am back from holidays and took a lot of pictures with the
Vario-Sonnar. It works seamless.

Here are some info regarding the conversion.

The first steps are the same as the ones that are on your site.

It is important to mention that the four screws have to be unscrewed
very carefully : they are much longer than the ones you provide so they
have to be kept in good condition. It is important to apply a lot of
pressure on the screw so that it will not get damaged.

Arriving to the removal of the diaphragm ring, things get different :

- the diaphragm ring is combine with the bayonet and a complex element
which is mounted with a second cam. In fact, both elements can be
separated easily but there is a trick : in order to separate both
elements, you have to remove the rubber ring that is around the
diaphragm ring. There is a hole at one point where you can access to a
screw. This screw has to be removed and afterwards, both elements can be
put apart.

- Afterwards, you can easily remove the lever like on other Contax lenses.
- The end of the conversion procedure is like what you explain on your
site. The small ball is located on the aperture ring.
- There is one more thing I have to say : you have to put back the four
long screws to fix the new Nikon bayonet. But they must not be tighten
to much : is it's the case, you will not be able to move the aperture
ring anymore.
Leitax note: I have the solution to this problem , please write me to info@leitax.com

- It is not necessary to shave any piece of the lens.

Hope it helps.



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