Originally Posted by johannielscom
Amazing! I've been shooting Leicas for over a decade and I've never known this!
After removing quite some crud (maybe 85 years
worth of it), I've found a '5' there.
Thanks for posting this!
Question though: is there a similar set of code numbers on 35mm and other focal length lenses that you know of, or are these numbers only on the 50mm lenses?
Reading some of those other threads out there, it sounds like there were marks on other lenses, like the 90? More research required