Repair of a pre-war 8.5cm (85mm) f2 Carl Zeiss Jena Sonnar in Contax mount

[former member]

The 8.5cm F2 Sonnar- the barrel "should" just unscrew, using a rubber pad. The rear group unscrews from the barrel once it is out. Getting the glass out should not be hard, unless someone has botched a prior "repair".

 

[TenEleven]

Yes, what Brian said.
Unless there's a grub screw in the back or it's frozen with old grease it should be reasonable to get out. You may even be able to do it with your naked hands. I posted this thread because it's an exceptional (read: not normal) horror story. Usually servicing these lenses is quite undramatic.

 

[Cascadilla]

Thanks to both of you for the encouragement--I may give this a try in the next few days.

 

[Miles.]

Is mounting the optical block into a Jupiter-9 barrel a possibility?

 

[former member]

Is mounting the optical block into a Jupiter-9 barrel a possibility?

I tried this once- the answer was no, the shape of the back of the barrel was changed and it would not fit. ALSO- the J-9 focus is too far off for a Leica standard camera. The best option is to use an Amedeo adapter with the Contax mount lens. That is what I do.