[Fluegel]

The upshot to this is that the cement separation can still be repaired. It takes a bit more work than a standard clean of fungus but it should still be doable from a specialist repairman.

That story is often heard of. Sofar I did not meet a repairman who could correct separation problems with lenses.

Whenever UV is used to harden the compound between the elements it is impossible to correct separation.
I do not know what method Pentax used in those days.

[yucatanPentax]

That story is often heard of. Sofar I did not meet a repairman who could correct separation problems with lenses.

Whenever UV is used to harden the compound between the elements it is impossible to correct separation.
I do not know what method Pentax used in those days.

There used to be a member here who could repair balsam separation of older lenses as well as reanodizing lenses in silver, etc. However, there was some unknown dispute and he's not here any more. Members who used his services were very happy with the lenses he repaired, so it was possible somehow.

I don't know when UV hardening came to be common.

[HarisF1]

There used to be a member here who could repair balsam separation of older lenses as well as reanodizing lenses in silver, etc. However, there was some unknown dispute and he's not here any more. Members who used his services were very happy with the lenses he repaired, so it was possible somehow.

I don't know when UV hardening came to be common.

I was going to mention his work but I think he has stopped doing repairs. DCShooter was his handle on these forums, he helped me out a lot with tips/advice on how to disassemble certain lenses.

[Fluegel]

Pentax must have used a different method than Carl Zeiss used.
There used to be a repair facility in the US that claimed they could correct separation and coating problems for Carl Zeiss lenses.
It was suspected they exchanged parts of lenses to be repaired for other parts.