I recently purchased the 45mm f/2.8 and 135mm f/4 lenses in this system with the intention of using them on a Sony A6000 via an available adapter, and hopefully testing their UV capability as well. When the adapter came in, it fit the 135mm lens just fine but would not mount the 45mm lens. I had no familiarity with the Zeiss 126 mount and no camera of this sort, so I didn't catch the problem until I had the adapter in hand.
It's an interesting mount, in that the actual mount mechanism is recessed in an outer housing that surrounds the lens elements, the housing of which protrudes unencumbered to the rear. Closer inspection shows that the 135mm lens has an aperture control tab that moves freely in a slot, while the same tab on the 45mm lens is stuck in a different position and appears to be blocking mounting of the lens. See the first two photos for a comparison of the breech ends of both lenses.
I had no response yet to my inquiry on Photo.net, so I decided to go ahead and open the problem lens up, something I've never done before. See the next two photos. My interpretation of what I found is that the entire diaphragm mechanism had been removed, and the disk that the aperture control tab moves and which actuates the diaphragm movement had been fixed in place. Thoughts from those who are familiar with these things? At this point I'm about to ask for a refund from the auction site but I thought I'd check first to make sure I'm right about this.
