I-61L/D made into Collapsible Contax Mount.

[Brian]

So I had TWO I-61L/D's. Now one is adjusted for the Leica,

http://www.ziforums.com/showthread.php?t=476

and this is how to make one for your Contax, Kiev, or Nikon RF.
Tools and Parts required for the Job. The Contax mount is from a Zeiss 5cm F2 converted to LTM, using a J-8 in LTM. The J-8 optics module will not fit into the Sonnar shell. But- the I61 has the same thread, correct back-focus, and will fit perfectly.


http://www.ziforums.com/picture.php?albumid=263&pictureid=2922

[Brian]

The aperture ring must be filed down so that the optics module can be screwed in far enough to the mount.

http://www.ziforums.com/picture.php?albumid=263&pictureid=2923

I use needle nosed pliers, a thin screwdriver will work.

Slide the retaining ring off.

http://www.ziforums.com/picture.php?albumid=263&pictureid=2924

The Ball-Bearing is under the aperture ring. It falls out, I use some tape to trap it.

http://www.ziforums.com/picture.php?albumid=263&pictureid=2925

[Brian]

http://www.ziforums.com/picture.php?albumid=263&pictureid=2926

The aperture ring has a rim around it- which must be filed down. It needs to be almost flush.

http://www.ziforums.com/picture.php?albumid=263&pictureid=2927

It is a soft aluminum, and files down easily.

[Brian]

Getting ready for re-assemble.

http://www.ziforums.com/picture.php?albumid=263&pictureid=2928

Getting the aperture ring back on: this screw will line up with the hole in the ring. Easiest to set the aperture wide-open, then line up for F2.

Slip the retainign ring back on.

http://www.ziforums.com/picture.php?albumid=263&pictureid=2929

[Brian]

You will need to use your camera to set the lens to agree with the viewfinder. I use a negative strip with scotch tape over it, and a loupe when working with the camera.

http://www.ziforums.com/picture.php?albumid=263&pictureid=2930

I get to cheat- use an adapter with the TTL viewer. When I want a Nikon RF lens, I set the lens to agree with the 5cm F1.4. When I want a Contax lens, I set it to agree with a Sonnar.

http://www.ziforums.com/picture.php?albumid=263&pictureid=2932

[Brian]

http://www.ziforums.com/picture.php?albumid=263&pictureid=2931

Final step: I use some epoxy to set the lens in the mount. You could mark the position of the lens, and make a shim. Better, but takes a lot of time. These are not expensive lenses, and this method "just works".

[rcbooth]

Actually the collapsible Sonnar shell can be made to accept the J8 optics module. I increased the thickness of shims used so that the J8 module didn't interfere with the shell and trimmed about 0.050" off the rear of the collapsible sleeve to achieve correct focus.

[Brian]

If you have photos of the process, I would appreciate if you posted a thread, or a link, to the process that you used.

[rcbooth]

I should e ale to do that - I'm about to do one for a friend.