It's is difficult to imagine the Hammer period horrors without color, gadfly. It was their trademark, and I doubt they'd done nearly so well in black and white. Of course Castle did well with b & w., but he was a one man band, not a studio. Hitchcock made a ton of money with Psycho but he was a franchise unto himself by that time, with his own TV series and short story anthologies that used his name. Hammer was built on period horror in color, is associated strongly with Cushing and Lee and in this sense was rather like the Republic (as in studio) of horror, with Peter and Chris their Gene Autry and Roy Rogers. Was there a pre-Hammer studio so dependent on horror, so strongly associated with it? (No, Universal doesn't count, as they did many other things.) I can't think of one offhand.