The Continuity System of Editing

The 'continuity system' is a set of editing rules in film set out to make sure the audience is not confused by the editing occurring in the movie. These include the 180 degree rule, 'match-on-action', eye-line match cuts, shot/reverse shots and establishing/re-establishing shots.

The 180 Degree Rule:

This rule involves the use of an imaginary straight line being used while filming called the 'axis of action'. The way this line is used involves the camera being on one side of the line throughout the scene and not being allowed to be used on the other side, as to not confuse the audience watching. This is due to the fact that if the camera was to randomly be used on the other side for certain shots in the middle of a scene, objects or people who were on one side of the frame when the camera was on one side will appear to be on the opposite one. So, to prevent this from happening and to prevent any confusion or immersion-breaking happening in the film, this rule should be followed strictly.

Match-on-action:

This rule makes it so that if an action is begun during the end of one shot, in order to keep continuity, that action should be continued into the beginning of the following shot. This means that the two shots flow into each other nicely, keeping the idea that they are genuinely directly following each other intact.

Eye-line Match cut (to POV):

The 'eye-line match cut' rule is quite similar to the 'match-on-action' rule in some ways. This rule consists of a shot where a character looks somewhere, for the next shot to be of the place that previous character was looking at. This rule being in place helps the viewer understand why the second shot is shown, as it helps them realise that the second shot was (in many cases) a POV (point-of-view) shot of the character in the first shot.

Shot/reverse Shot:

This rule is usually used the most often during scenes that include dialogue/a conversation, more often than not between two characters. The rule states that the camera(s) used for the two shots (forward and reverse) should be the opposite angle of each other against the 180 degree 'axis of action' line.

Establishing (or re-establishing) Shot:

The 'establishing' shot of a scene often takes place at the beginning of the scene, but can in some cases happen in the middle of one instead. The purpose of this rule is to show where the objects or people in the scene are in relation to others also there. Without this shot present, the audience would struggle knowing where each thing shown on camera is supposed to be, as without a shot establishing this, they could technically be anywhere, like apart from each other or in different locations.