Uncommon Common Lenses

[SimonMaddock]

There was a barrel Rodenstock Ysarex 300mm, I think f4.5, on ebay a few years ago. I made a saved search thinking I might get one should they turn up again. I haven't seen one since. No photos on the googles and I can't find any other info. I didn't realise it was as rare as it seems to be. It's "just a tessar" after all.

[MAubrey]

Did it come from the factory that way? Seems odd to put that lens on such a larger shutter for so little gain in light.

I think it was originally barrel mounted. But its threads are #3s, like many Fujinon lenses.