Continuity in Film.

Shot Reverse Shot

Shot reverse shot is a film technique where one character is shown looking at another character and the other character is looking in the opposite direction, which implies the two are looking at one another. This is often used when the scene involves two people talking. This creates a realistic effect to the audience that both characters are interacting. The primary elements of a shot/reverse shot sequence are derived from the three-camera set up. The shots you should have for a basic shot reverse shot are: a two-shot of the characters usually in wide or medium shot; an over the shoulder shot on character A; and an over the shoulder shot on character B. The diagram below should give you an idea of the set up. (https://www.youtube.com/watch?v=FiWrkLJDQCQ)

180 Degree Line Rule

This rule is essential in keeping the viewer focussed and avoiding confusion. Once the scene has started the camera has to stay one side of the actors and action. This is called the 180 Degree Line Rule. In a dialogue scene between two characters, a straight line can be imagined running between the two characters, and extending to infinity. If the camera remains on one side of this line, the spatial relationship between the two characters will be consistent from shot to shot, even if one of the characters is not on screen. Shifting to the other side of the characters on a cut will reverse the order of the characters from left to right and may disorient the audience. The rule also applies to the movement of a character as the "line" created by the path of the character. For example, if a character is walking in a leftward direction and is to be picked up by another camera, the character must exit the first shot on frame left and enter the next shot frame right. (https://www.youtube.com/watch?v=y4wX_dmh8_g)

Match on Action

Match on action is a very simple but is essential, where the perspective of the camera changes during a scene and the scene continues the flow of the film. An example is a man walking up to a door and reaching for the knob. Just as his hand touches the knob the scene cuts to a shot of the door opening from the other side. Although the two shots may have actually been shot hours apart from each other, cutting on action gives the impression of continuous time when watching the edited film. By having a subject begin an action in one shot and carry it through to completion in the next, the editor creates a visual bridge, which distracts the viewer from noticing the cut or noticing any slight continuity error between the two shots. (https://www.youtube.com/watch?v=Mv93covb53w)