FSU lens and RF adjustment on Canon P

[02Pilot]

I recently purchased a Canon P body. My intent is to use my Jupiter-12 and Jupiter-8 on it. While checking and adjusting the RF calibration I found that it is not possible to have both close (1m) and infinity settings on the RF correct; with close focus set properly, the RF image goes beyond the VF image at infinity. The variation is similar with both lenses, so this appears a function of either FSU/Leica incompatibility or the RF cam follower eccentric requiring adjustment. I do not have a Leica-standard lens with which to check at the moment, so I do not know which of these possibilities it is.

My thinking is that if the problem does come down to FSU/Leica compatibility (as I suspect it might), I should keep the RF adjusted for close focus, accepting the fact that while the RF may be slightly off at longer distances, this is unlikely to have a practical effect on image focus except possibly on the Jupiter-8 when shooting wide open at distant subjects. It seems to me that DOF should take care of the RF/lens inconsistency in most cases, while I should be able to accurately focus on close subjects.

Just looking for a check here to determine the validity of my process. Thanks.

 

[t6un]

Makes sense to me. Scale focus is easy beyond 5m or so.
It could sill be annoying to constantly shift between the two different focussing methods, and you would have a "gray area" around 2m where neither of them would work at their best.
So if you plan to stay true to russian lenses for a while, i would still
advise to get the camera's rf cam length adjusted. I did, and haven't had a chance to regret it yet. Because I only have russian lenes for it.

 

[02Pilot]

It's not that I have any particular attachment to FSU lenses over others, it's simply that the LTM lenses I have are all FSU at this point. I'm looking into getting a couple of longer focal length lenses which would not be FSU, as my understanding is that the incompatibility becomes more problematic at longer focal lengths, but I simply cannot justify the usual prices of 50 and 35 LTM lenses that precisely meet the Leica standard when I have the Jupiters which I know work well. Just trying to get the most out of what I have.