NORTH MIAMI, Fla. — Steven Krams was 5 years old when his father took him to see the family comedy “Who Killed Doc Robbin” at the Elm Theater in Brooklyn, N.Y. But instead of looking at the screen, the young Krams kept staring up at the projection booth, intrigued by the beam of light emanating from within. “My dad said, ‘I know the projectionist here.