Quote Originally Posted by Sal Santamaura View Post
Bob provided a complete answer in his post (#2). Everything after that has served only to confuse the matter.

First, although supplies are dwindling, new Copal shutters are still available. Second, shims are used to fine tune cell spacing so that optical variations can be compensated, not because of shutter manufacturing tolerances. Those optical variations are more than an order of magnitude greater than Copal's thickness tolerance.

Using Rodenstock as an example, shims ranged from 0.5 to 1.5mm. Copal shutters carry a thickness tolerance of ±0.025mm.
So who does this fine tuning, Sal... the yenta that’s mating a lens to a shutter? Based on some optical measurements?