F stop scales!!!!!!!!!

ruilourosa · Jul 17, 2012

hello

I am planning a compact and cheap lens kit like 210, 270, 305 all clarons... and i have a compur 1 where they all fit nicely, how could i do a f stop scale for the shutter (since i plan to use only that one and doing some screwing and unscrewing as i change the different cells), has anyone did this already? i know that convertible lenses have something like this, is it possible?

thanks!

Rui Lourosa

ic-racer · Jul 17, 2012

SK Grimes

ruilourosa · Jul 17, 2012

ok it has been done!!!! i think i will try to make one myself, it seems a nice project...

it would be nice to have scanned scales for different lenses, different focal lenght´s and different shutters, i think i will do it for the lenses and shutters i own!!! that way it would be easyer for new shuttering projects!!!
working for the community!!!
scans are welcome!!!

Rui Lourosa

Fotoguy20d · Jul 17, 2012

210 here

TimmyMac · Jul 17, 2012

Get a shutter with a scale for the 305. The 210 will be almost exactly one stop faster than the 305 at equal aperture needle settings. So f/11 on the 305 scale will be f/8 on the 210, f/16 will be f/11, etc.

270 doesn't work as well, so... just don't bother carrying a 270

E. von Hoegh · Jul 17, 2012

TimmyMac said:
Get a shutter with a scale for the 305. The 210 will be almost exactly one stop faster than the 305 at equal aperture needle settings. So f/11 on the 305 scale will be f/8 on the 210, f/16 will be f/11, etc.

270 doesn't work as well, so... just don't bother carrying a 270

Use the 210 component on the rear and the 305 component on the front, you'll get about a 255mm combination.

Ian Grant · Jul 17, 2012

Schneider once sold a Symmar convertible/combination set for a very short time, but you should in theory be able to use any Combination of Symmar cells in a shutter they fit. That should be possible with Plasmat type G-Clarons as well.

Ian

E. von Hoegh · Jul 17, 2012

Ian Grant said:
Schneider once sold a Symmar convertible/combination set for a very short time, but you should in theory be able to use any Combination of Symmar cells in a shutter they fit. That should be possible with Plasmat type G-Clarons as well.

Ian

The Dagor type G-Clarons can be mixed (not with the Plasmats, AFIK) and matched, as well. So can Goerz Dagors.

ruilourosa · Jul 17, 2012

Interesting!!!

crossing cells would affect quality? what about spacing... many questions!!!!!

thanks

Rui Lourosa

E. von Hoegh · Jul 17, 2012

ruilourosa said:
Interesting!!!

crossing cells would affect quality? what about spacing... many questions!!!!!

thanks

Rui Lourosa

Correct spacing would be a job for an expert, which I am not.
But, if you tweak the spacing until you get a flat field at say 50x the focal length, it will work surprisingly well. I did this with some old Dagor lenses from 6" to 300mm.

ruilourosa · Jul 17, 2012

thanks fotoguy, i will post my measurements and my sales as soon as i do them!

Jim Jones · Jul 18, 2012

Instead of making the scales, calculate a correction chart for the other lenses and whatever scale is on the shutter.

E. von Hoegh · Jul 18, 2012

Or, have a scale showing the iris opening in millimeters and use the chart.

ruilourosa · Jul 18, 2012

i much prefer to have a direct reading of the f stop i´ll be using... it´s not hard to do the math but i teach and for the students it´s just a complication!

F stop scales!!!!!!!!!

Privacy & Transparency

Privacy & Transparency