This is the Vario-Sonnar 3,4/35-70 zoom lens.
Which can be as good as primes just stopping it down a bit
First, unscrew the four screws from the mount base, and just lift the aperture ring and bayonet all together, you'd have to rotate a bit to the left and to the right to liberate them.

Now, as this is a push-pull lens, put the rear optical group at the higher position and keep it there with rubber bands.

Grab this holding ring firmly and unscrew it.


The last optical group can be removed now.

Removed components

Now look at this threaded
ring, we have to unscrew it too.

I have not the special tool for this, so I've just pushed the small gaps in opposite directions to make it turn

Finally is out.


Now we have to remove this flat cover, rotate it a bit to avoid those screws at the barrel and just turn the lens upside down, it will fall
Now look at the small spring, we have to make it pull to the right...

... so I've attached it to that screw on the right side.

See it in more detail.

Ok, you can remount everything on its place and go for the final step.

Now we need to scratch the glue that secures the small spring to the  perforated ring, so we can remove this ring.

This step is not  necessary for the conversion to Nikon.
Replace the aperture ring and add some grease at the bearing ball hole.

For Sony and Nikon cameras, before putting the aperture ring on the lens, remove the lever you can see at the picture fastened with two screws.
Only this lever, not the one under it, that controls the iris.

So we can put the perforated ring on it, pay attention to the picture for  the correct position
, please check that the bearing ball is still in place.

For Nikon cameras, we don't use the perforated ring, and we have to remove the aperture lever

Now install the Leitax bayonet for Contax MM lenses on it.

Ready, now we can use this very good lens on Pentax and Sony cameras.
Contax NikonAnd now, on Nikon F-mount cameras too.
Back to Leitax
Back to Contax for Pentax
Back to Contax for Sony
Back to Contax for Nikon