Quote Originally Posted by BetterSense View Post
I took both my lenses off and had a look. They have the same threads, but the Beseler actually is held in with a threaded nut on the top side, rather than screwing straight in. Now I'm torn between which lens to keep, since the Beseler looks and feels much higher quality but the Rodenstock lens on the Omega has cool light-up F-numbers.
Actually the lenses work the same way - it is the lensboards that are different (one has a threaded hole, while the other doesn't).

I prefer the ones with the retaining ring (the "threaded nut") but that is probably just me.

Tell us what the printing on each lens says and we will be happy to pass on our opinions .

You need to be quite exact, because just a two letter difference in the lens name can be quite important.