Sinaron SE 135mm from DB-board to Copal 0?

**vrangnes** · 11-Dec-2021, 06:56

I know there are several similiar threads, but as far as I know no one regarding this switch/focal length:

I bought a Sinaron SE 135mm, but it's currently mounted in a Sinar DB-board. I have a 150mm Symmar-s with a Copal 0 and I'm thinking about swapping the glass.
Should this introduce any other problems than that the aperture scale will be off? And how much will the scale be off? I assume that this is related to the focal length and 135mm and 150mm is not that far off from each other?

I'm aware that there might be some shims that needs to be moved as well, but other than that I hope this will be a smooth operation

**Richard Wasserman** · 11-Dec-2021, 08:40

I would definitely try it. I did exactly what you want to do with a 210mm Sinaron SE and it was a perfect fit in its new shutter.

I'll leave the aperture scale issue to others...

**vrangnes** · 11-Dec-2021, 10:18

Originally Posted by Richard Wasserman

I would definitely try it. I did exactly what you want to do with a 210mm Sinaron SE and it was a perfect fit in its new shutter.

I'll leave the aperture scale issue to others...

That sounds very promising. Were there any shims on your 210mm that you had to "transfer"?

The Sinaron SE is still in the mail, so I have to wait until Monday before I try anything at all.

**Richard Wasserman** · 11-Dec-2021, 10:20

Originally Posted by vrangnes

That sounds very promising. Were there any shims on your 210mm that you had to "transfer"?

Yes I believe there was a shim. I kept everything just the way it was on the DB board when I transferred the lens to the shutter

**vrangnes** · 11-Dec-2021, 12:05

Ok, I've tried to do some research 'n math regarding the aperture scale:

If I understand correctly (I probably don't) I should calculate it like this:

135/150 = 0.9
5.6 / 0.9 = 6.2

Which means that 6.2 on the 150mm scale = 5.6 for the 135mm?

**vrangnes** · 14-Dec-2021, 01:20

Mounting the 135mm in Copal 0 was no problem at all. There were two tiny shims on the front cell, and I managed to transfer them without breaking anything.
It seems like everything is optically in order, but I have not had time to shoot any test sheets yet.

**Richard Wasserman** · 14-Dec-2021, 09:10

Originally Posted by vrangnes

Mounting the 135mm in Copal 0 was no problem at all. There were two tiny shims on the front cell, and I managed to transfer them without breaking anything.
It seems like everything is optically in order, but I have not had time to shoot any test sheets yet.

Sounds promising! Please let us know how it works out when you have time to test it with some film