The 180-degree rule is a fundamental principle of cinematography that is used to maintain visual coherence in film and video production. This rule states that the camera should maintain the same side of a shot, relative to the subjects, throughout a scene.
The 180-degree rule is based on the idea that the audience has an innate sense of spatial orientation and that this orientation should be maintained in order to provide a clear and coherent visual representation of the action. The rule states that the camera should always remain on one side of an imaginary axis that runs through the center of the action, and that the axis should never be crossed. This allows the audience to maintain a clear sense of the spatial relationships between the subjects in the scene, even as the camera moves.
The 180-degree rule is most commonly used in scenes that involve two or more characters who are facing each other, such as in a conversation or an argument. In these scenes, the camera should be positioned on one side of the axis, and should remain on that side throughout the scene. This means that the camera should not cross over the axis and change sides, as this would create a disorienting and confusing visual experience for the audience.
In addition to maintaining visual coherence, the 180-degree rule is also used to create a sense of continuity in a scene. When the camera remains on one side of the axis, the audience is able to see the characters' physical movements and expressions more clearly, which helps to create a more immersive experience. The 180-degree rule is also used to create a sense of visual tension and drama, as the camera can be positioned in such a way as to emphasize the action or the emotional state of the characters.
There are, of course, exceptions to the 180-degree rule, and some filmmakers choose to violate the rule in order to achieve a specific visual effect. For example, crossing the axis can be used to create a sense of disorientation or to convey a character's confusion or emotional state. However, these instances are relatively rare, and most filmmakers adhere to the 180-degree rule in order to maintain visual coherence and continuity in their films.
In conclusion, the 180-degree rule is a fundamental principle of cinematography that is used to maintain visual coherence and continuity in film and video production. This rule states that the camera should maintain the same side of a shot, relative to the subjects, throughout a scene, and that the axis should never be crossed. By adhering to this rule, filmmakers are able to create a clear and immersive visual experience for their audiences, which is essential for effective storytelling.
Source: American Society of Cinematographers (ASC). "The 180 Degree Rule." American Society of Cinematographers, www.theasc.com/education/asc-knowledge-center/the-180-degree-rule.