Remounting a Velostigmat.

[cowanw]

I have recently received a 8 1/4 inch Series ll Velostigmat in a Betax shutter and a 9 1/2 inch Soft Focus Series ll Velostigmat in Barrel. I plan to use the Betax for both. the threads all fit perfectly but I will need to lengthen (adapt) the 9 1/2 inch lenses by 3/8 inch to keep the lenses the same distance apart in the shutter as originally in the barrel.
My question is can this be done all on one side (i.e. in front or behind the shutter diaphragm). Or is it necessary to keep the diaphragm in the same relative distance vis a vis the front and back lenses ( i.e. a 3/16 extension on the front and back of the shutter).
Regards
Bill

[Darryl Baird]

Just mount the 9.5 inch into the shutter and shoot it... if it's soft focus you're after you should be fine. Before somebody shoots me for heresy, I had the same situation and assumed I'd need a front mounted adapter to match the air space. I thought I'd try the lens anyway and found I had a pretty good lens after all. It might not (from what I tested) be as sharp, but it certainly was nicely soft to my eyes.

[cowanw]

Thanks for your response Darryl. Given the front element is made to move I suspect there is a lot to what you say, and the picture always tells the tale.
It is in my nature to try to understand the theory of whatever I am putting my mind to. I had hoped that the lens sachems would have a comment on applicable lens theory.
Jim,Ole, Dan
Fred, Barney, Wilma are you out there?
Kindest Regards
Bill

[Jim Galli]

Thanks for your response Darryl. Given the front element is made to move I suspect there is a lot to what you say, and the picture always tells the tale.
It is in my nature to try to understand the theory of whatever I am putting my mind to. I had hoped that the lens sachems would have a comment on applicable lens theory.
Jim,Ole, Dan
Fred, Barney, Wilma are you out there?
Kindest Regards
Bill

The aperture should be positioned exactly the same in both apps. If that requires 2 extension barrels, that would be the deciding factor. But it never hurts to take pics first.

[Darryl Baird]

It is in my nature to try to understand the theory of whatever I am putting my mind to. I had hoped that the lens sachems would have a comment on applicable lens theory.
...Bill

I too want to know more, but I have limited time each week to pursue these "quests" and I get really impatient and hungry to "just do it." As long as I don't break something I can usually go back to the original state of things and start again. That's how I sometimes blunder into a happy outcome, plus it is really satisfying to "arrive" at my destination through personal decisions with minimal help, advice, and guidance. This forum is a fantastic resource and I've learned as much from reading old posts as asking questions in the moment.