My Pentacon 300 has languished in the cupboard. Belatedly I have made a move, and took the mount to the local engineering shop. I instructed them to take down the shoulder by 1.3mm, to allow for some shimming to align the lens and for potential use with cameras with longer registration distance. The plated conducting flanged PK M42 adapter is 0.8mm thick.
Now I can mount and demount the camera with reasonable ease, the attachment is tight and the exposure compensation resides around +1-2eV, giving me a reasonable adjustment range, instead of locked on the top end at +3eV. Caveat: I normally suffer a mirror flop from the K-r after each shot (and I haven't dared try burst mode...! ).
Took advantage of a day of autumnal sunshine to take my usual test pics of the castle turrets. Sharpness already good from f4, and very little CA/fringing. But contrast was quite weak, improving markedly with stopping down. Memo: make a bigger hood.
Then I just needed the regular denizens of the creek on the south side of the castle to be reasonably cooperative: the ducks and the swan family. The pentacon has a vibration resisting mass and solidity on the tripod. Focus is inherently slow with a long focus throw, more so because the movement is a little stiff. Focus in the VF wasn't snappy - that weak contrast? - but I was still annoyed at a lot of front focussed shots, must bear that in mind next time. Mind you I don't have my split prism, it remained in the body I sent off for repair, but I am using the tenpa 1.36x. Best samples from the session:
f4
crop:
f8
Lumix G1: