text: The eye is not a video camera: there is no "frame rate" or "scan rate" in the eye: instead, the eye/brain system has a combination of motion detectors, detail detectors and pattern detectors, the outputs of all of which are combined to create the visual experience.\n\nHowever studies have shown that "persistence of vision", which is what allows us to turn individual frames into motion, starts to see flicker around 16 frames per second.  That's why film and video are have settled on rates above this threshold (though really early films were not.)  This also accounts for refresh rates in TVs, computer monitors, etc.