The 180° Rule

The 180 degree rule is a wide spread technique used during the filming process which keeps the camera one one side of the action. Below there is a diagram which displays a axis of action. When taking the rule into account the camera must stay on one side of the axis throughout the scene. This ensures that the characters are composed in a fixed position in the frame. Additionally if this rule is ignored or not used to execute a shot correctly it could risk giving the impression that the actor's positions have been inverted or reversed.