Loose light baffle on 21 mm 4.5 Biogon

[Cascadilla]

I recently acquired a 21 mm f/4.5 Zeiss Biogon for my Contax IIIA. Negatives look great, but after I have used it for a while and go to remove the lens from the camera, the extra light shielding baffle around the rear elements that can rotate when you focus works loose and falls off when I remove the lens from the camera. I have noticed a couple of set screws that look like they should allow this to revolve without falling off, and I have gently tightened them, but the problem continues. Does anyone have any ideas on how to fix this?

 

[Bill Jones]

Cascadilla,

Actually it's not a light baffle but a lens protector. The Conarex version of this lens does not have it and the lens will give perfect images without it. The risk is hitting the rear element on the shutter as you mount the Biogon. So you could leave the protector off if you are very careful mounting the lens. Alternately you could tighten the set screws so the protector is securely mounted but still rotates and put a tiny drop of clear fingernail polish on the screw heads using a tooth pick.

Bill

 

[Cascadilla]

Thanks for the info. I will look probably take your suggestion and remove it permanently and carefully store it.