The 180 degree rule

                      

                        The 180 degree rule

The 180-degree rule is a cinematography rule concerning the space between two actors within a frame. Imagine an invisible line, or axis, passes through the two actors. Under the 180-degree rule, the camera can move anywhere on its side, but it should not pass over the axis. Keeping the camera on one side of the 180-degree line makes sure the actors keep the same left/right relationship with one another. Scenes filmed this way look orderly and can be easily followed.

video for reference

A camera breaks the 180-degree rule if it crosses the imaginary line. By breaking the 180-degree rule, the camera captures a shot called a reverse angle. Reverse angles are disorientating for viewers. While a reverse angle can add dramatic impact in some circumstances, it can often distract viewers and undermine the scene.

how to break the rule

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