180 degree rule

This schematic shows the axis between two characters and the 180° arc on which cameras may be positioned (green). When cutting from the green arc to the red arc, the characters switch places on the screen.

The 180° rule is a basic film editing guideline that states that two characters (or other elements) in the same scene should always have the same left/right relationship to each other.

Rule

The rule gets its name from the 180° arc that extends from a point on the other side of Alice from Bob, to a point on the other side of Bob from Alice, within which Alice and Bob will always have the same left/right orientation.

The 180° rule is also often called "The Line", or the "Line of Action". An imaginary line can be drawn between two characters, and the camera should stay on one side of this line. Breaking this rule is most commonly referred to as "crossing the line." It can also be referred to as "breaking the line of action", or "breaking the 180° line". In TV circles this is often referred to as "Crossing the axis" - in effect you would be able to see the camera!

Examples

In the example of a dialogue, if Alice is on the left and Bob is on the right, then Alice should be facing right at all times, even when Bob is off the edge of the frame, and Bob should always be facing left. Shifting to the other side of the characters on a cut, so that Bob is now on the left side and Alice is on the right, will disorient the viewer, and break the flow of the scene.

In the example of an action scene, such as a car chase, if a vehicle leaves the right side of the frame in one shot, it should enter from the left side of the frame in the next shot. Leaving from the right and entering from the right will create a similar sense of disorientation as in the dialogue example.

Style

The 180° rule is an essential element of a style of film editing called continuity editing. The rule is not always obeyed. Sometimes a filmmaker will purposely break the line of action in order to create disorientation. Stanley Kubrick was known to do this. Directors Yasujiro Ozu and Jacques Tati sometimes ignored this rule also.[1]

Some filmmakers state that the fictional axis created by this rule can be used to plan the emotional strength of a scene. The closer you place the camera to the axis, the more emotionally involved the audience will be.

See also

* Continuity editing
* 30 degree rule

Notes

References

Further reading

Books:

External links:
*Animated examples of the 180 Degree rule
*Some excerpts on the 30 Degree rule as well.