View Full Version : Focusing mount

27-Sep-2001, 19:06
Hi there......I have the schneider 150 mm focusing mount for the apo symmar. I a m wondering whether I can use it with the Rodenstock 150mm apo sironar S? The co pal shutter is both # 0, both lenses weight identical but the filter size of the symmar is 58mm and sironar is 49. Any comment will be appreciated. Thanks in ad vance.

Jim Galli
28-Sep-2001, 02:39
Renee I'm confused. When you say focusing mount, are you talking about a helical mount that moves the lens back and forth in relation to the film like some of the older medium format cameras had? What kind of focusing mount, camera, and what is the application?

Walter Glover
28-Sep-2001, 07:26

I f what you mean is that you intend fitting one lens and its shutter onto a helical focussing mount to replace another lens already fitted then you can probably do it. However, the flange focal distance of the two lenses is different (Schneider = 144.2mm ... Rodenstock = 147mm) and so focus will have to be checked on the GG. Also, if it is the Schneider that is fitted to the mpount and you switch to the Rodenstock you will be able to extend the focus barrel and achieve infinity focus; the reverse would not be possible.

If, on the other hand, you intend just switching over the front and rear components there is still the issue of focus, plus the necessary caution with any shims included with the front section AND the difference of the aperture scale.

Proceed with caution ... only IF YOU MUST>

Cheers ... WG

Bob Salomon
28-Sep-2001, 09:45
You will need the proper Rodenstock helical. There is a Rodenstock helical Focusing Mount for all Rodenstock lenses in 0 and 1 shutters. Each one, of course, is calibrated for the specific focal length and has the proper DOF scales for that focal length/ Yhey mount to any lensboard that accepts a 3 shutter as it has the same thread size.

28-Sep-2001, 12:43

Is their a helical mount for the 115 and 155 Grandagon? Since you state all 0 & 1 I would be interested in helical mounts for these two lenses if available.

Please provide part # and from whom I can order.


Bob Salomon
28-Sep-2001, 15:01
It is a miscellaneous part so it is ordered by description. Any dealer can call us and order it for you.