When I was in New Orleans in 2014 shooting my poker scene with Ben Mendelsohn for “Mississippi Grind,” the script supervisor came over after every take to capture photos of the table, reset the chip stacks, make sure our hands were in the right places, see if I still had my bowtie on, etc. I was fascinated by the detail work. That’s why I love this piece about what script supervisors do on a movie set, featuring Martha Pinson, who has done that job for Martin Scorsese for many years…