Kiron/Vivitar 100mm f2.8 Macro fungus

[bjolester]

I have a very good Kiron made Vivitar 100mm f2.8 Macro that has some kind if contamination on the inside of the rear lens group. The rear lens group is easy to remove from the lens. How do I open the rear lens group to get to the affected glass element?

PS: This lens is identical to the Kiron 105/2.5 and Lester Dine 105/2.5 macros.

I am grateful for any advice on how to fix the lens!

 

[Duofold RF]

most likely you need to remove the ring part with slots, it may glued, a drop of nail polish remover may help

 

[bjolester]

most likely you need to remove the ring part with slots, it may glued, a drop of nail polish remover may help

Thank you for helpful advice! I tried to unscrew the ring with slots from the lens group assembly, only using hand power, but with no success. I have read somewhere that Kiron were infamous for using a lot of thread-glue in their lens production. Most probably I will send the lens to a professional technician for cleaning the affected glass element, I do not have the tools or the competance to fix it myself. The Kiron/Vivitar 100/2.8 Macro is very very good, so probably worth the expense of a cla.