Quote Originally Posted by Ian Grant View Post
Luckily f stop markings on rimset Compur, Copal, Epsilon, Prontor are evenly spacesd. older dial set lenses have scales which are circular versions of your second drawing.

Ian, have your vision checked.

I just took a look at some of my shutters. Rimset Compur (Compur-Rapid #0, Synchro Compur #0 and #1), uneven spacing. Prontor Press #0, even spacing, #1, uneven. Copal Press #0 and #1, even, Copal cock-and-shoot #0 and #1, even. Epsilon (not sure where it fits in the Compur/Copal scheme, it holds a 105/3.8 Xpres), uneven.

With uneven spacing, the smaller the aperture, the shorter the steps.