After principal photography is concluded, the production process moves to postproduction. Postproduction transforms the thousands of feet of raw footage into a finished film. One of the most important elements of postproduction is the editing process in which shots are selected and assembled in an appropriate order. Attention is then turned to the soundtrack. While the majority of US films record dialogue on set, some parts may be rerecorded due to poor sound quality. Music and sound effects must be recorded and the different tracks combined into a final mix. Opening and/or end credits must also be added, and other optical and visual effects work may be required.
Editing, like script development, goes through several stages. Traditionally, the editing process has involved working with a physical copy of the film, cutting and splicing pieces of footage manually. It is now more common to load the images onto a computer using a system such as Final Cut Pro or Avid, which allows easy experimentation with different ways of arranging the shots. Whichever method is used, the basic processes remain the same. First, the dailies are assembled in the order specified in the shooting script. Excerpts are then taken from individual shots and arranged in such a way as to tell the story as economically as possible, while at the same time preserving a sense of coherent time and space. This is traditionally referred to as the "rough cut." Although normally it does not have a soundtrack, it is generally a reliable guide to the finished film.
The editing that produces the rough cut often uncovers deficiencies that had not been detected before. A common problem is that shots do not fit together well because the director did not film enough coverage of the action to clarify the spatial relations between them. More rarely, the movie may simply be too short. This happened with Duel at Silver Creek (1952), when director Don Siegel paced the action too quickly. The resulting rough cut ran for only fifty-four minutes, far too short for a feature release. The obvious remedy in such situations is to shoot additional footage, but it is one most producers strive to avoid because of the difficult logistics and potentially great expense of reassembling actors and sets.
While the editing is taking place, work is carried out on the soundtrack, with different crew members working on the music, sound effects, and dialogue. Normally the composer does not begin work until after viewing the rough cut, but in rare cases the musical score is written before filming begins. Ennio Morricone's music for Il Buono, il brutto, il cattivo ( The Good, the Bad, and the Ugly , 1966) and John Williams's score for Close Encounters of the Third Kind (1977) are well-known examples of such a practice. Sound effects are often taken from existing recordings held in sound libraries, but some films require the creation of new effects. This process is undertaken in a recording studio by a foley artist. It may also be necessary to record postsynchronized dialogue. This normally entails placing the actors in front of a film projection so they can ensure their lip movements match the image.
The different pieces of sound are recorded on separate tracks. They are combined in premixes, which are the sound equivalent of the visual rough cuts. As the editing of the image track progresses, the sound needs to be remixed in accordance with the lengthening, shortening, rearranging, or deleting of scenes. This process has been made easier by the development of computerized sound-editing software.
When the editing of the image track has been completed, a copy of the original negative is cut to match the edited print. A new positive print, known as an "answer print," is struck from the edited negative. This print is then graded, which ensures that color and light levels are consistent throughout the film. The process may be repeated several times before unwanted variations are eliminated. At the end of this process, a print called an "interpos" is created, from which another negative, called an "interneg," is struck.
Work on the final version of the soundtrack is also completed at this stage. The final sound mix is made to synchronize perfectly with the finished image track, and the sound is recorded onto film in order to create an optical soundtrack. A negative is created from this and combined with the interneg. Any titles and optical effects are also added at this stage. The resulting combined optical print will be the source of the "interdupe" negative, from which the final release prints will be struck.
Throughout postproduction, executives of the producing or distributing company carefully monitor the progress of the film. If dissatisfied with the results, they may insist on changes, sometimes even replacing the original editor and/or director. This may happen at any stage from the rough cut onwards. The insistence of studio executives on their right to determine the final cut has frequently resulted in bitter conflicts with directors who often regard themselves as the "authors" of the finished film. A confrontation that entered the Hollywood annals took place during the studio era between MGM and director Erich von Stroheim. Producers were alarmed by von Stroheim's forty-two-reel (approximately nine- or ten-hour) rough cut of Greed (1924). Aware that a film of this length could never be screened commercially, von Stroheim cut almost half the footage himself, and then handed the reduced version to a trusted associate for further editing. The results failed to impress MGM executives, who demanded further cuts. When von Stroheim failed to comply, they appointed their own editor, and cut the film down to the more marketable length of ten reels.
If the studio is uncertain about the audience appeal of a film, it will often undertake test screenings in order to gauge reaction and obtain guidance for improvements. Test screenings may be repeated several times until audience scorecards indicate the film has attained the desired response. Reediting, or even reshooting, may be required if audience reactions fall short of expectations. Recent films that were substantially altered following test screenings include Troy (2004), which replaced Gabriel Yared's score with completely new music by James Horner, and King Arthur (2004), for which a new ending was shot and the violence toned down. With each batch of changes, however, the postproduction cycle must be repeated, as new versions of sound and image track need to be married and new negatives and prints created.
It is also common to prepare multiple versions of films for release in different countries. Perhaps the most obvious feature that needs to be localized is the language. Often the dialogue is dubbed into local languages, which means the newly recorded voice tracks need to be remixed with the music and sound effects. Title sequences may be replaced completely—sometimes with entirely different visual designs—or subtitles may be added to the existing credit titles. If the film has not been dubbed, dialogue subtitles will be needed throughout the film.
Language is not the only feature that varies between countries, however. Different censorship regulations mean that sequences allowed in one country may have to be removed in another. Obviously this can affect spatial and/or narrative coherence. Sometimes major changes are made to a film in order to give it greater appeal outside its home territory. Francis Ford Coppola's first directorial assignment (under the pseudonym of Thomas Colchart) was to take the Japanese disaster film Nebo Zovyot (1960) and completely reedit it for US audiences, transforming the plot and adding not only new dialogue but also new footage. The film was released in the United States as Battle Beyond the Sun (1962).