I motion stabilized the critical frames of the JFK shooting. The shot caused the cameraman to jerk.
You can see that he was hit in the head from the front by an incendiary round, which caught fire, exploded his head, and jerked it backwards.
He was slumped forward from a previous rear shot. The incendiary device struck him in the front of the skull and lodged there. You can see flames shooting out of the front of his skull in each subsequent frame. His skull was jerked sharply backwards over the next quarter of a second, and by the last frame you can see that much of his skull is gone.
Oswald was behind him.