Quote Originally Posted by pstake View Post
I am not sure ... looks like lens separation and Jon seemed to think that's what it was.
Only the rear lens group is cemented in a normal Tessar like yours, so you can be sure that it's just coating damage. It can look like lens separation due to the thin-film interference pattern that is common in both cases. In one case the thin film of canada balsam is separating, and in the other it's the antireflection coating.

http://en.wikipedia.org/wiki/Thin-film_interference

You said earlier: "
Quote Originally Posted by pstake View Post
There's some separation on the Tessar 45 on my ZI Contaflex II. Mr. Jon Goodman who frequently makes wry (and quite funny) comments on these forums, and who used to repair Contaflexes et. al, said that lens-separation is pretty common among these models.
Mr. Goodman probably made a mistake about your Tessar, and thought of the Pro-Tessar auxiliary lenses for the later Contaflex models. They have cemented lens groups in the front.

Jon, I know you are reading this!