View Full Version : 121 Sa into a copal 0 shutter

22-Sep-2011, 12:30
i purchased one of these lenses in a bad shutter i have a 135mm in a very nice copal 0 shutter which i know the 121 will fit into, what i was wondering how far off will the aperature be, the shutter is a 5.6, the 121 is an f8

22-Sep-2011, 13:32
With a Copal shutter having linear spacing between it's stops, it should be no problem to put 8 in place of 5.6, if it is as maximum opening. Stops count up from there.
Older shutters with exponential spacing (due to inverse square law) would require recalibration for each stop.

Jim Galli
22-Sep-2011, 14:55
1/3 stop