This was my Dad's wstch. Bought in Lebanon. It's a Seamaster Calendar from around 1952 or so. First watch with a calendar made by Omega i think.
If you don't count the original Cosmic triple-dates, then yeah, it's the first Omega calendar. Let's go with Omega's first automatic calendar watch. Love the black waffle dial on yours! gatorcpa
Do you have any photos without filters? It looks nice don't get me wrong but I'd like to see the true colors of the dial, nice to see how a dial aged over time