Second unit

Second unit is a discrete team of filmmakers tasked with filming shots or sequences of a production, separate from the main or "first" unit. The second unit will often shoot simultaneously with other unit or units, allowing the filming stage of production to be completed faster.

The functions of the second unit vary, but typically the first unit films the key face-to-face drama between the principal actors. Two frequent ways a second unit is used are:

In both of these scenarios, the purpose of the second unit is to make most efficient use of some of the resources that are expensive or scarce in film production: actors' and directors' shooting time, sound stage usage and the cost of sets that may have been built on stages, and the money that is tied up in a film as it is being made – the quicker it can be finished, the sooner production costs can start to be earned back.

The work of second units should not be confused with multicamera setups, where several cameras film the same scene simultaneously. Large productions may have multiple second units. Although filmmakers may refer to having "three or four units working", each unit would be called an "additional second unit"; usually none would be described as the third or fourth unit.

The second unit has its own director and cinematographer. A key skill for a second unit director is to be able to follow the style being set by the film's primary director. Peter MacDonald, second unit director on X-Men Origins: Wolverine, The Bourne Ultimatum, and Harry Potter and the Goblet of Fire, has said, "The most important thing about any second unit is that you can't tell the difference between the second unit and the first unit. It must have the stamp of the first unit, both in photography and the style of direction. ... You try and copy what the first unit does as much as possible. You mustn't be on an ego trip and try and do your own style, because your material has to cut into theirs and it mustn't jar, it must fit in exactly so no-one can tell the difference."Brett Ratner, commenting about Conrad Palmisano, who directed second unit for Ratner on Rush Hour 3 and After the Sunset, said, "He has the understanding of what it takes to create a great action sequence and never deviate from the story or the tone of the film."

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