Simone, this is an amazing job! The lens looks like a real "product"!
Thanks Akira, it starts to have a charm common to restored products that are cobbled together from non-original materials. It is amazing how much can be done by combining existing parts -- so far I did not have to add any new material apart from the bayonet mount and the set screws, everything else is done from original parts of the two lenses. For example, the part from the Contax lens that I'm holding loosely in reply #11, was cut right where the thin section ends, and the thin section has an outer ring that can be removed. The exposed part (approx. 10mm long) fits into the Topcor 50/2 focusing ring, not too tightly but maybe with half a mm of space. So I when I cut the part, I left some of the large diameter section and then removed just enough to give a sliding fit (maybe 0.1mm of space to prevent it from rubbing). Of course this does not provide weather sealing but is good enough for now. I guess with better tools one could even put a groove for an O-ring there. The original stack holding the aperture ring can now be attached with the original screw. By using some tape, I achieved a tight fit between the ring that attaches to the front of the lens assembly. This will be attached properly with screws later. What remains to be done:
- shim the lens correctly to fix the slight tilt of the lens assembly resulting in unequal sharpness in the upper and lower half of the image.
- affixing part of the original helicoid case that has the indents for the ball bearing for the aperture clicks. This will be tricky to get the tolerances right and assembly will be tricky as well, but we'll see how it goes. Worst case the lens stays de-clicked (as there is no CPU contact it does not matter anyway whether one sets a precise f/stop or not).
- screwing the front barrel together.
- some cosmetics. E.g. I don't like the gap between the DOF scale and the mount. I want to use some leftovers from the Contax lens to wedge in-between.
