Visible crew/equipment: When Ratchets gets up from the dining room table after Poirot turns him down, you can see the cameraman in the silver buffet on the table.
Visible crew/equipment: In the apartment scene with Dustin Hoffman and Valerie Perrine, he prances in front of a vanity mirror, and a big boom microphone is right over his head, hanging deep into the shot, reflected in the mirror. The boom microphone is quickly retracted, so they knew they had made a mistake, but the shot remained in the finished film.