The 180 Degree Rule

The 180 Degree rule

The main use of the rule is to establish an establishing shot to show a scenic area such as a park and also to the maintain actions of the characters on screen; you do this by establishing a line of action. This line is normally placed in-between two actors(it's preferable that one is facing left and the other right when standing still and talking); or along a path that the character is moving from. The 180 degree comes into play when you establish the line of action on the two subjects then place a camera on the side you have chosen to use; this camera is now part of the 180 degree arch on one side of the action line. You can now place your cameras at any angle on the 180 degree arch you have allocated and still not break the sight line. In contrast if you place the camera on the opposite side of the action line then the actors are facing the opposite direction then they were previous; this may confuse the audience.

Another example of the 180 degree rule is when an actor is walking. Imagine the action line is the path the actor is walking across; now if you place a camera on the left side of the line you can freely switch between angles and still know which way the actor is walking. In contrast if you place the camera on the right side of the action line while the actor is still walking then it will appear to the audience that the actor has turned and walked in the opposite direction. A good example of a moving action shot is in any sport in which a player is running sown the pitch to a goal-line(for example football). During the tense moments in which the player is running with the ball to score a point on the opposite end of the pitch switching the camera to the opposite side of the action line would confuse the viewer as it would show the player running in the opposite direction.

You can however switch cameras to opposite sides of the action line to add effect; for example if a character is drunk and stumbling through the street you could switch action line sides to induce a feeling and confusing to the audience.