I just purchased a 50mm Distagon for a 500CM. Wow, these are finicky! The slow speeds are anybody's guess and switching from self timer and "X" is also questionable. How does one get into the green speeds for long exposures? This particular lens won't let me turn the shutter speed either coupled or uncoupled from the aperture (EV values). Also, the DOF preview is slow and sticky. I understand these are older lenses, but i'm not sure I got what I paid for regarding this 50mm Distagon. Any hints?
I have the same lens, a 1973 model Zeiss Distagon 50mm f/4 T*. I don't find the lens "finicky" at all. You just have to understand how to operate it, and it has to be in good condition to operate consistently and reliably.
If the shutter is inconsistent, it needs to be serviced. Same for the self timer and X sync. The DoF preview should just click once, you can then rotate the shutter/aperture ring together to see different DoFs, and if you go to wide open in the course of doing that, the aperture setting will have been reset.
I presume you mean that the shutter speed ring will not turn past B, whether coupled or uncoupled from the aperture / EV Value scale. This is normal: The green indicator numerals on the shutter speed ring, from B onwards, simply matches up with the aperture settings to tell you what exposure time past 1 second you need at those aperture settings for the EV value you've set. In use, you set the speed ring at B and then, after reading the correct time pair from the ring for the EV setting you've select, you unlock the aperture ring and rotate it to set the aperture. The shutter speed must remain at B because you are manually timing the exposure.
You can find the year of your lens by going to
http://www.hasselbladhistorical.eu and inputting the lens serial number in the appropriate place on the page. If it needs service (and it most likely does at this age), look up David Odess. He does excellent service work on Hasselblad gear.
G