Quote Originally Posted by Tom Hoskinson
Roman, please check the other responses in this thread.
I did. But that doesnīt prevent me from judging my own experience and talk about it. ;-)

I canīt see any variability on side of the J12 lenses - but on the side of the Cosina bodies. Mine fits my Bessa L with a comfortable margin and others come close with their shutter curtains. But it never came in contact with the shutter and I never heard of such a case in "Real life" - and I keep tracking the topic for a few years now (owning and using sovkams of all shades and tastes).

LZOS (the source of most J12s in M39) hasnīt changed them that much - not optically, just a bit on the mount side (shifting from "White" aluminium and alloys to black enameled aluminium). But not on the dimensions - it would have required a recalculation of the design. Which hasnīt occured in the 40 years of production of Jupiter12.

I donīt know for sure since I never disassembled a Cosina "Bessa" body and I donīt think I will ever own another than the "L" stored somewhere around here - but could it be that they used different shutters in production?