at the time of 5247, almost all dramatic TV shows were shot on 35mm film. that generated a LOT of "short ends" --> rolls of film between 100 to 300 ft. (anything under 100ft tended to just get tossed, as what can you do with a 1 minute shot time when you still have to do a slate and anounce the shot for the sound track.)
Many small labs gathered those ends cheep and bulk loaded and sold them as still rolls. the film could only be processed by a movie lab and so they would process and do a contact print on whatever was the equivelent of x383
(which unfortunately included some print stocks where the dyes were optiomized to look good when new, rather than lasting)
Seattle actually started to use unmarked c-41 film (proably from Ferrania) and counted on any still labs being scared off.