Doubts about Jupiter 12 in a Canon 7

[Agustin]

I bought a Jupiter 12 black body at a good price to use with my Canon 7. When mounting the lens it seems to touch somewhere in the camera. Someone told me that I should lightly file an area of the inside of the body so that I will not have difficulty focusing. I took everything to a local technical service who told me that it was not necessary to touch anything. With use the rubbing parts would be eliminated. Those who use this camera combination with the Russian lens, have you had the same problem? If so, how have they solved it?
Thanks from Buenos Aires, Argentina

 

[xayraa33]

I use the J-12 on the Canon 7 and it fits fine with no obstruction.

J-12 back ends do vary from different years and some can rub the side light baffles on the Canon 7 camera.

 

[retinax]

If something rubs, filing is likely not the solution - the baffles can be gently bent (at your own risk).

 

[Dan Daniel]

Don't file.

If you remove the lens, turn the camera upside down, you'll see a round metal disk- this is the rangefinder coupling. surrounding it is a serrated metal sheet. The lens is hitting this metal sheet. You can put a finger inside and press lightly on the metal sheet- BEHIND THE RANGEFINDER COUPLING! Do not press the rangefinder disk. Press lightly and see if you can reshape the metal sheet slightly upwards and out of the way.


You can open the back and lock the shutter open on B (cable release with lock is safest) and see where the rubbing is happened with the lens mounted. Also set the lens to closest focus- fully extended- screw onto the body and then slowly move focus to infinity. This pulls to rear bulb back and might show you that you only need to reshape a small section.

 

[Agustin]

Thank you very much to all of you! I did the thing indicated by Dan Daniel. The Jupiter 12 works correctly. Next weekend I'll use it with Ilford film. I will show the results.
Agustín