Principal photography

Principal photography is the phase of producing a film or television show in which the bulk of shooting takes place, as distinct from the phases of pre-production and post-production.

Besides the main film personnel, such as the actors, director, cinematographer(s) or sound engineer(s) and their respective assistants (assistant director, camera assistant, boom operator), the unit production manager plays a decisive role in principal photography. They are responsible for the daily implementation of the shoot, managing the daily call sheet, the location barriers, transportation, and catering. Additional typical roles during filming include the script supervisor to record changes to the script and the still photographer to produce images for advertising and documentation.

Several reports are prepared each day to track the progress of a film production, including the daily production report, the daily progress report, and the sound report.

Principal photography can take place in a studio or in an actual setting, and the choice of location depends on artistic and economic aspects. While shooting in a sound stage offers more accurate planning, constructing sets may be expensive. Costs and artistic reasons (see French New Wave and Dogme 95) are the main drives behind filming on location. However, outdoor shooting requires more effort because equipment and personnel must be transported to the location. In the early days of cinema, filmmakers tried to film outdoors as much as possible, as sunlight was needed to ensure adequate exposure of poor-quality early film stock; nowadays, due to the increased use of CGI, more shooting is done in a studio.

Depending on the laws of the respective country, the producer must obtain filming permits from private individuals, authorities or companies for the selected locations before filming begins. An extensive production may require closing the area with signs and diversions. A filming permit within an urban area usually requires a fee, which depends on the complexity and scope of the filming as well as the attractiveness of the location.

Once the locations have been set, the screenplay is summarized in a script breakdown with all information relevant to the shooting. Under the supervision of the producer, the unit production manager prepares the production schedule, production board, and shooting schedule to work out the exact sequence in which the scenes in the script will be shot. Due to a great many considerations beyond the scope of this article (but addressed at length in the production board article), the sequence of the scenes to be shot normally does not follow their chronological sequence in the script. These schedules are then used to build the daily call sheets, which summarize the relevant information from the schedule and lists exactly who has to be on the set for a planned daily shoot. At the same time, the call sheets provides information about the scene numbers, script pages and locations relevant for each day, as well as the necessary equipment.

Feature films usually have insurance in place by the time principal photography begins. The death of a bankable star before completing all planned takes or the loss of sets or footage can render a film impossible to complete as planned. Furthermore, professional quality movie cameras are usually rented as needed, and most camera houses do not allow rentals of their equipment without proof of insurance.

All this meticulous planning is necessary because time equals money. Every hour spent on set resolving issues which could have been resolved earlier—while the cast and crew wait for filming to resume—equals thousands of dollars which will need to come out of some other portion of the film's budget. As of 2012, the average "day cost" for an American film ranged from as low as $25,000 for low-budget films, to $35,000-$60,000 for midlevel budget films, to as high as $100,000-$250,000 for blockbuster films. The first assistant director is paid very well to keep filming on schedule and within the original budget, and may be replaced (that is, fired) if the production strays too far from its original schedule and budget.