Som Berthiot Cinor B 12.5mm 1.9 dissassembly

[zanxion72]

I have this wonderful minuscule D mount lens and it has oil on the inner side of the rear element. It looks fairly simple to disassemble and from a first look it seems being a two element objective.
Is that the case? Before delving deep into it, does anyone have any experience with it?
It on my beautiful little Bolex Paillard C8, a double 8 film cine camera.

[Olivier]

Hello Zanxion.
I found this link about this lens : http://www.lenaturaliste.net/forum/viewtopic.php?f=56&t=16436&start=0

And this one about the 25mm f1.9 https://www.youtube.com/watch?v=fJ9tV4eXoA8

If they are of the same design, it's looking simple to dismount from front and rear with a spanner wrench.
I would risk opening it.

[zanxion72]

[Olivier]

and from the front, after unscrewing the front lens, maybe you could access the oily glass ?

[zanxion72]

I have tried with a spanner to get the black retaining ring off the lens, but at no avail. Removing the focusing ring I can see the block that it gets hooked on but i cannot move it I have tried to ease things with a bit of lighter fluid, but it is still stuck.

[Olivier]

Maybe try to drop carefully some WD40 droplets with use of a syringe ?

[zanxion72]

I didn't try that. I will get WD40 and try a few drops of it.

[screwunscrew]

The Cinor B 12,5 is a four-elements lens, namely the former Perlynx by Hermagis (1924). Benoist-Berthiot took over Hermagis in 1934.