Archived posting to the Leica Users Group, 1998/01/09
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Damian, The 35/2,8 M3 as well as the 35/2 for M3 (i.e. with goggles) can be converted to SM us quite easily. At the bottom of the mount ( the steel ring that holds the goggles in place) there is a small set screw. If you remove that, you can then unsrew the lens from the mount and the thread for the lens corresponds to the Leica 39mm thread mount. Bear in mind that the focussing accuracy is now thrown out the window, the mount for the goggles are thicker than the regular S-M bayonet and you are going to have to adjust the lens/film plane to fit. The simplest way to do that is to use a regular S-M adapter, put it on a M-camera and put a groundglass screen on the back of the filmrails. Pick 3-4 points at set distances, say 1m,3m 10m and infinity. Check that the lens focusses correctly at these distances ( and that the scale on the lensbarrel corresponds to these distances). You might have to do several checks and shift the lens in the mount ( by unscrewing or tightening it in the S-M adapter). Once you got that right, measure the space between the S-M adapter and the back of the lensmount flange. This would indicate the thickness of shim material you would need for having the correct lens/film plane distance as well as the correct focussing with the cameras cam. It is a lot of work, but once you got it done it works well. You just use the shim everytime you mount the lens on the screwmount body. You can use the lens without the shim, but then you have less precise focussing, particularly shooting wide open. The advantage is that you can put the lens back in the "goggle" mount when you want to use it on a M camera ( dont loose that little setscrew, it is miniscule). Be careful when you unscrew the lens the first time. It is most likely several decades since that lens was removed from the mount and it might be stiffer than you thought to undo. I dont know if it is worth the effort, but it certainly would keep you busy for several evenings and you can justify a lot of shots by going " I am just testing this lens". Good luck Tom A