Filter sizes

[Iskra 2]

Need a filter step-up ring for a 360/5.5 Tele Xenar. My Googling/searching hasn't returned the info needed. I have several 77mm filter accessories used with my RB 67 and want to adapt them to the Xenar. I think the Xenar front lens threads are 72mm but would like to confirm before purchasing.

Also, would like to get a retaining ring for the lens rather than mounting to the lensboard with Liquid Nails.:o :eek: I presume, any #3 shutter retaining ring would work, maybe not though. Appreciate any help. Regards.

[Robert A. Zeichner]

The Schneider 360mm f5.5 Tele-Xenar takes a 67mm .075 pitch screw-in filter, which is a common size. As far as the retaining ring for a # 3 shutter is concerned, these can be any number of different diameters and thread pitches. Even shutters of the same model can differ, depending on what lens it was designed to acommodate. I have several Universal #4 shutters, as an example, that take a couple of different size rings.

[Ole Tjugen]

There were a couple of different "incarnations" of the 360/5.5 Tele-Xenar, and i wouldn't be at all surprised if they had different filter threads.

If the shutter is a Compound, that will be a "standard" Compound #3 size. The threads are different from Copal #3 which is again different from Copal #3s; and US made Ilex, Alphax and other shutters have different threads too...

[Iskra 2]

Found the calipers and roughly measured the dimensions. Looks like the filter dimension is about 67mm and the rear threads are about 60mm. I'll order using these as standard sizes and take a chance on the thread pitch. Thanks for the quick responses. Regards.

[Ole Tjugen]

It's a 60mm 29 1/13 tpi thread - more commonly known as M60x0.9, but a ring cut with that thread wouldn't fit.

SK Grimes has flanges and retaining rings with the correct thread (even if they use the wrong designation).

[Iskra 2]

Ole, is thread depth (or something else) involved that doesn't match?

[Ole Tjugen]

The difference is in the slope of each thread. F. Deckel, for some strange reason, decises to use a 50 degree pitch. Standard metric thread is 60 degrees... A metric thread ring will fit on, but be a little bit too tight.

[Iskra 2]

Thanks for the info Ole. These correct retainers are not cheap.:eek: Hmmm, maybe there is another way.:D Regards.