Film Techniques: 180 Degree Rule

The 180 Degree Rule is a basic rule that means two characters should always have the same left and right relationship together. When the character crosses the axis connecting to two subjects it is called crossing the line. The new shot is called the reverse angle.

This schematic shows the axis between two characters and the 180 degree arc on which the cameras may be positioned (green), when cutting from the green arc to the red arc, the characters switch positions.