As most of us who use old lenses know, there were a number of different systems used to calculate and define the aperture variations on a lens. I'm curious whether anyone knows of a resource that cross-matches the equivalents of the different systems?
BTW, here are the systems I know of:
f/stops (aka, the "International System")
Continental System (same as the f/stop system, but with the standard stops in different places, ie: 4.5, 6.3, 9, 12.5...)
Alternative System (same as the f/stop system, but with the standard stops in different places, ie: 3.5, 5, 7, 10...)
Uniform System
APEX System
Stolze System
Dallmeyer/Goerz/Voigtlander Systems (same as the Stolze system, but with the standard stops in different places along the scale)
French System
Zeiss System
Anybody know of any others? (Apparently, some very early lensmakers assigned arbitrary values. but we won't count those!)
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