The hand that presses the speaker button on Cameron’s phone belongs to John Hughes. When the crew left, Hughes took the camera and shot it himself since no one else was getting it right.
Ferris Bueller’s Day Off (1986)
“Jeanie? Is that you? I can’t see very far. Jeanie?”
“If anyone needs a day off, it’s Cameron.”
Ferris Bueller’s Day Off, 1986 (dir. John Hughes)