Because of this 3-word optical phenomenon, still images projected at 24 frames per second seem to be moving pictures
Though not developed by them, the first motion picture projector and ... One 
immediate problem: the Lambda partners were still following the practice of 
moving the film ... of 24 fps derived from AT&T's averaging of filming and 
projection ... something to which they were particularly sensitive because one of... [DOC] [TLE] Animation.ppt [PAR] Animation is a type of optical illusion.