Xenotar lens separation?

[wkh]

Or maybe I am missing the point totally.

Frau Schönfelder from Foto Olbrich has correctly identified the lens issues but stated that they should have no influence on the photo quality. The last owner, a retired professor, told me that the lens was like this when he brought the camera used in the 80s. He took hundreds of photos with it and never see any issue or artifact.

The camera is a tool (even if it is a beautiful one) and should be used instead of looking pretty on a shelf. I should not be so fixated on its defects and spend the money on films instead...

 

[WayneWolfe]

I still repair separation. Just haven't been on Photrio lately. I am no longer able to strip and recoat, however. All that stuff is still packed up after moving.

Thing about using heat is that doublets separate specifically because the coefficient of thermal expansion of the crown and flint have a very significant mismatch. Flat bonding surfaces do not reduce the stress induced with heating, and I have seen the soft glass that flints are made of flake like an arrowhead with heat. It is always a risk. Much less risk using a solvent to separate.

p.s. soaking in a 10% sodium chloride (table salt) solution for several days and then wiping clean will remove those old MgF2 coatings if you want to eliminate that damage.

I still repair separation. Just haven't been on Photrio lately. I am no longer able to strip and recoat, however. All that stuff is still packed up after moving.

Thing about using heat is that doublets separate specifically because the coefficient of thermal expansion of the crown and flint have a very significant mismatch. Flat bonding surfaces do not reduce the stress induced with heating, and I have seen the soft glass that flints are made of flake like an arrowhead with heat. It is always a risk. Much less risk using a solvent to separate.

p.s. soaking in a 10% sodium chloride (table salt) solution for several days and then wiping clean will remove those old MgF2 coatings if you want to eliminate that damage.

Hi Nodda Duma,
Checking to see if you can me with a lens with seperation on a rear element of a 20mm lens.
Thank you.
Wayne Wolfe