The camera
and some from the roll.
There is a light leak to be corrected, but besides it the old instrument worked. It is nice to have 16 MF frames. I overexposed a bit, sometimes way too much, and the scanner had a tough job with that last frame - it was two stops overexposed.
This camera has a mechanism for counting frames based on rotation of the take-up reel, that depends crucially on the diameter of the reel. In a separate thread, Alex gave me the diameter for the wooden reels that were used when the Semi was new (modern plastic ones are a bit slimmer). I did try different diameters (using tape), with spent rolls, and watched how the frames aligned at the end of the roll. They were off by at least 1 cm, in different directions, depending on how the film was getting into the take-up reel.
In the end I decided to rely on the yellow window, because the frame alignment was kind of unpredictable. In a word, I chickened.
This was my first roll with HP5+ in some years, and I have more coming to vary from my usual FP4+. Tried D-23 1:1 in this one.
. For all I know it is still down there.