Assistant director

The role of an assistant director on a film includes tracking daily progress against the filming production schedule, arranging logistics, preparing daily call sheets, checking cast and crew, and maintaining order on the set. They also have to take care of the health and safety of the crew. The role of an assistant to the director is often confused with assistant director but the responsibilities are entirely different. The assistant to the director manages all of the Director's in development, pre-production, while on set, through post-production and is often involved in both personal management as well as creative aspects of the production process. Historically, assistant to director was a stepping stone to directing work; Alfred Hitchcock was an AD, as was James McTeigue. This transition into film directing is no longer common in feature films. It is more common now for an assistant to the director to transition to a production management or producer role than to directing.

Often, the role of assistant director is broken down into the following sub-roles:

The sub-roles of assistant directors differ among nations. For example, the distinction between second second AD and third AD is more common in North America. British and Australian productions, rather than having a second second AD, will hire a "second" 2AD experienced in the same duties, and trained to the same level, to allow a division of the duties. 3ADs in Britain and Australia have different duties from a second second AD, and the terms are not synonymous.

One of the first AD's most important responsibilities is to "call the roll" — that is, call out a series of specific cues for each take to ensure that all cast and crew on set are aware of exactly what is going on so they can perform their particular role at the appropriate moment. Over the years, special procedures have been developed for this task to achieve maximum efficiency during shooting, which are usually some variant of the following:

The above roll sequence can be varied by, for example, eliminating the sound calls and the clapping of the slate if the shot is mute or "MOS" ("MOS" is a universal abbreviation for "Motor Only Shot"). At other times, for expediency (e.g. if the shot begins with a closeup of a closed door which then opens), the slate may be shown at the end of the take rather than the beginning. In this case, once the sound is rolling, there is an audible announcement of "End board" (also "end slate," "tails," "tail slate," or "tail sticks") so that the editing department knows to look for the sync marks at the end of the action. At the conclusion of the action, the director will still call "cut", but the first AD (and possibly others) will immediately call "end board!" or so that the camera and sound recorder are not turned off before the clapper is clapped. Also, as a visual cue to the editors, the clapper-board will be shown upside down on camera.

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