I was asked if the Jupiter-12 fits and works on a Canon P. Seems like a simple question, but when I searched the web I got something of a 50/50 yes/no results.
My own experience is that the J-12 does not work in the Cosina/Bessa rangefinders, since they have some remnants of the mirror box. But the Canon is from the late 50's and was meant to be fully Leica-compatible.
So, does anyone have this combo and can answer if the J-12 does not hit/obstruct anything inside the Canon P?
There are several versions of the Jupiter-12: I have seen early ones jam-up on a Canon III, perhaps due to the difference in the RF followers. My 1952 KMZ J-12 with Zeiss SN's stamped internally works perfectly. I've used later versions without problems.I've used them on the Canon P and Canon 7.
The light baffles of the Canon P and Canon 7 interfere with some lenses- including some collapsible lenses when collapsed.