Thanks! Glad you enjoyed! So my version of the lens was made between 1957-1960. The first variant of this lens was made in 1949. The only things that really changed was the housing and coatings, not the optical structure. I shoot pretty much all vintage manual lenses. I have a Canon FD 55 1.2, Canon FL 58mm 1.2, and a Nikon 50mm 1.4. For a focal length I don't shoot too much, I have a lot of options :P