I was asked by a pro. documentary maker (who I met on the plane flying in to London) to get some B role for a G&R concert he was filming (with his spare video camera).

I was given the camera and sent in to the mosh pit to film from that perspective. After the show I gave the camera back to him. He said, "where's the footage?"

I had been "filming" looking through the view finder, but I had forgotten to press record.

Gutted.