View Full Version : Remount a DB-lens into a Copal shutter?

24-Aug-2007, 13:20
Another newbie question. Is it easy to remount a lens on a Sinar DB/DBM-board into a Copal-shutter, if one have a Copal shutter that is made for the same type of lens? Or are, for example, the lenses on the DB/DBM-boards made especially for those boards?

John Schneider
24-Aug-2007, 13:42
Maybe yes, maybe no. Some lenses will mount fine in shutters. Some DB lenses (the 90mm f5.6 S-A comes to mind) have a groove turned into the rear barrel to allow it to clear the protruding DB mount rear thread. These rear cells will only bottom out in a shutter when they contact the diaphragm, both preventing the diaphragm from moving and giving an incorrect lens cell spacing. There may be other common problems that I have not personally experienced.

24-Aug-2007, 13:45
Thanks! How about Nikkor 450mm and Apo-Ronar 480mm?

24-Aug-2007, 22:43
I wasn't aware of this shortcoming---I was actually planning on remounting my 90/5.6 sa in a copal 0 because it's getting a bit hard to work with for far objects with significant swing/tilt.

is there a spacer or a flange to work around this?

also, are there other db mounted lenses which have altered cell grooves?

Bjorn Nilsson
25-Aug-2007, 01:16
For most lenses it should be a simple matter of unscrewing the front and back lens elements from the DB mount into the shutter. The "normal" problem is that e.g. a Copal 3 (in your case) will do the trick, but the aperture scale needs to be made for that particular lens. (Or at least that particular focal length of that type of lens.)