and landscape shots, establishing shots and intermediate images as well as for mass, action and stunt scenes. The length of the filming depends not only on the length of the film, but also on the number and type of locations. The shooting time for a 90-minute film in Europe is 12 to 100 days. In the USA, depending on the film project, a shooting time of 15 to 20, 40 to 50 or, for larger productions, 80 to 100 days is used as a basis for studio productions, although in other countries the shooting takes considerably longer. Because of breaks in recording and subsequent shoots that are difficult to calculate, the principal photography is usually planned longer than actually necessary. Once a film concludes principal photography, it is said to have wrapped, and a wrap party may be organized to celebrate. During post-production, it may become apparent that some shots or sequences are missing or incomplete and are required to complete the film, or that a particular scene is not playing as expected, or that a performer needs to be replaced entirely. In these circumstances, additional material may have to be shot. Follow-ups When using analog cameras, the exposed photographic film from a day of shooting is rushed to a photographic processing lab for development overnight, and then the developed raw footage is viewed by the director, cinematographer and producer the next day to determine whether reshooting is needed. With digital cameras, the so-called dailies can be viewed immediately after they are recorded. If the material proves to be inadequate or faulty, a re-shoot will be carried out on the day of shooting (digital) or on the day of the viewing (analog). Sometimes, additional shooting is needed after principal photography is complete, because the shots already made have subsequently turned out to be unusable or additional shots are required. For example, serious deficiencies in the narrative structure may become clear only after filming (such as when a rough cut of the film is put through test screenings with audiences who have not had the benefit of reading the screenplay in advance). Other reasons for re-shoots may be the production company's desire to make the film more commercially appealing, or the replacement of actors whose performance was lacking or who no longer fit the project after significant revisions to the film's plot or tone. If the new material has already been