Schneider G-Claron 150mm f9 Shutter Size?

**dave_whatever** · 31-Aug-2013, 02:45

I remember that on my shutter the point where the shutter blades just almost became visible, the lenses f/9, was about f/13 on the shutter.

On the other hand a set of Sinaron-SE cells go in without adjustment.

**mitch.goddard** · 31-Aug-2013, 12:17

Here's what the rear end of the front cell should look like.

**Andrew** · 31-Aug-2013, 14:34

Originally Posted by IanG

The scales should be almostnthe same, the only variations is because some 150mm lenses can vary slightly and actually be 148mm t0 152m. The aperture is related to the FL and the diameter of the aperture.

f stop = focal lenght/diameter of aperture

Which reminds me I have to make an aperture scale for a 14" Telephoto lens max aperture f4.5 but with no scale at all (or shutter).

Ian

I'm also surprised there was such a big difference! I have both those lenses so I'm tempted to try that particular swap and see what happens

but there are apparently other variables to consider such as flange to film plane distance.... and that'll be a prominent issue you'll have to allow for when you're dealing with a telephoto design

edit:

Originally Posted by dave_whatever

I have used 150mm g claron cells in the shutter from a 150mm symmar-s and the aperture scale needed about one stop of correction (off the top of my head I can't remember if it was one stop smaller or larger).

I just did the experiment and, on my examples, I make the difference 0.4 f-stops with the 150 g-claron having less light transmission so I'd expect to have to add 0.4 f-stops using the aperture scale from the 150 symmar-s ???