Canon FD 55mm f/1.2 S.S.C. vs Olympus OM-System Zuiko Auto-S 55mm f/1.2

What actually differs

• Both open to f/1.2, so neither has a speed advantage.
• The Canon FD 55mm f/1.2 S.S.C. is cheaper. Typical used value is $320 against $500, a gap of $180 (roughly 1.6x). Ranges: $180 to $600 versus $300 to $900.
• Both are 55mm lenses, so framing is identical on the same sensor.
• The Olympus OM-System Zuiko Auto-S 55mm f/1.2 is the older design; production began around 1972 against 1973 for the Canon FD 55mm f/1.2 S.S.C. (1972-1984 versus 1973-1979).
• They use different mounts, Canon FD and Olympus OM, so each needs its own adapter. Both reach infinity on mirrorless bodies with a plain mechanical adapter.
• Construction differs: 7 elements in 5 groups for the Canon FD 55mm f/1.2 S.S.C., 7 elements in 6 groups for the Olympus OM-System Zuiko Auto-S 55mm f/1.2.

Which one to buy

On the catalog data the Canon FD 55mm f/1.2 S.S.C. wins on the $180 lower typical price, and the Olympus OM-System Zuiko Auto-S 55mm f/1.2 gives up nothing measurable in return except its own rendering, described below. Condition and variant matter more than the spec sheet at these prices.

Minimum focus distance, weight, and measured sharpness are not in the catalog, so this comparison does not claim anything about them.