The multiple-camera setup, multiple-camera mode of production, multi-camera or simply multicam is a method of filmmaking and video production. Several cameras—either film or professional video cameras—are employed on the set and simultaneously record or broadcast a scene. It is often contrasted with a single-camera setup, which uses one camera.
Description
Generally, the two outer cameras shoot close-up shots or "crosses" of the two most active characters on the set at any given time, while the central camera or cameras shoot a wider master shot to capture the overall action and establish the geography of the room. In this way, multiple shots are obtained in a single take without having to start and stop the action. This is more efficient for programs that are to be shown a short time after being shot as it reduces the time spent in film or video editing. It is also a virtual necessity for regular, high-output shows like daily soap operas. Apart from saving editing time, scenes may be shot far more quickly as there is no need for re-lighting and the set-up of alternative camera angles for the scene to be shot again from the different angle. It also reduces the complexity of tracking continuity issues that crop up when the scene is reshot from the different angles.
Drawbacks include a less optimized lighting setup that needs to provide a compromise for all camera angles and less flexibility in putting the necessary equipment on scene, such as microphone booms and lighting rigs. These can be efficiently hidden from just one camera but can be more complicated to set up and their placement may be inferior in a multiple-camera setup. Another drawback is in the usage of recording capacity, as a four-camera setup may use (depending on the cameras involved) up to four times as much film (or digital storage space) per take compared with a single-camera setup.
A multiple-camera setup will require all cameras to be synchronous to assist with editing and to avoid cameras running at different scan rates, with the primary methods being SMPTE timecode and Genlock.
Film
Most films use a single-camera setup, but in recent decades larger films have begun to use more than one camera on set, usually with two cameras simultaneously filming the same setup. However, this is not a true multiple-camera setup in the television sense.
Some films will run multiple cameras, perhaps four or five, for large, expensive and difficult-to-repeat special effects shots, such as large explosions. Again, this is not a true multiple-camera setup in the television sense as the resultant footage will not always be arranged sequentially in editing, and multiple shots of the same explosion may be repeated in the final film—either for artistic effect or because the different shots can appear to show different explosions since they are taken from different angles.
Television
Multiple-camera setups are an essential part of live television. The multiple-camera method gives the director less control over each shot but is faster and less expensive than a single-camera setup. In television, multiple-camera is commonly used for light entertainment, sports events, news, soap operas, talk shows, game shows, variety shows, and some sitcoms, especially ones filmed before a live studio audience.
Multiple cameras can take different shots of a live situation as the action unfolds chronologically and is suitable for shows which require a live audience. For this reason, multiple camera productions can be filmed or taped much faster than single camera. Single-camera productions are shot in takes and various setups with components of the action repeated several times and out of sequence; the action is not enacted chronologically so is unsuitable for viewing by a live audience.
In multiple-camera television, the director creates a line cut by instructing the technical director (vision mixer in UK terminology) to switch between the feeds from the individual cameras. This is either transmitted live, or recorded. In the case of sitcoms with studio audiences, this line cut is typically displayed to them on studio monitors. The line cut might be refined later in editing, as often the output from all cameras is recorded, both separately and as a combined reference display called the q split (a technique known as "ISO" recording). The camera currently being recorded to the line cut is indicated by a tally light controlled by a camera control unit (CCU) on the camera as a reference both for the talent and the camera operators, and an additional tally light may be used to indicate to the camera operator that they are being ISO recorded.