Need help with a Sinaron Lens (DB Mount)

[Vincepad]

I'm aware of what a DB Mount is, but I'm wondering if I can remove the cells and mount them in a copal shutter. Specifically, I'm looking at a 210 Sinaron-S in a DB mount. I have a Fujinon 210 that I got for free. The Fuji has has rear cells that are badly damaged and basically unusable. I would like to purchase the Sinaron-S in a DB mount and remount the cells in the Copal 1 shutter from the Fuji. Is this possible? FWIW, KEH has a Sinaron-S 210 in a Copal 1 shutter, so I'm thinking it's possible.

Am I missing something?

Thanks!

[Phil Hudson]

Sinaron-S 210mm f/5.6 cells will fit a Copal 1 shutter, yes. The aperture scale on the shutter needs to match that focal length as well to be correct for the new cells. Sometimes thin shim rings are needed to get the spacing absolutely correct when remounting cells but this might be a job for a repair shop with the right test apparatus. In general the transplant will work fine for most uses.

[Peter Yeti]

Phil is right, the DB mount takes standard size cells and the only issue is adjusting the spacing with shims. I did it with several old lenses without problems. Since there are some manufacturing tolerances in the shutters, the lens makers figure this in by making the cell threads slightly shorter. Then the adjustment is made by shim rings. So, if you have a properly mounted lens to transplant, you could measure the overall length accurately. This length needs to be exactly reproduced after mounting in the new shutter. You'd only need to be able to measure accurately to 1/20 mm, which isn't easy and requires appropriate tools. Schneider and Rodenstock always have been very kind and sent me shims and aperture scales when needed.

Good luck,

Peter

[Vincepad]

Thanks! This is very helpful!