Before beginning any film that involves controlled lighting, choices should be made on the lighting style you hope to achieve. The cinematographer and director can look at films, photographs and paintings. In documentary films, flat bounce lighting is used sometimes to ensure that the entire filming space is sufficiently bright and to allow the camera and subject to move without the lights being repositioned. The fact that a location looks deliberately lit rather than naturally lit may be of little concern or perhaps defended on the grounds that this is “truer” to the reality of filmmaking. The black-and-white fiction films of the 1930s look lit in a different and highly stylized way. These films were usually made on sets with scores of lights that bathed the actors from lighting grids above and around the sets-places where lights could never be located in a normal building interior. In many feature films today, the prevailing lighting aesthetic is naturalism. Although many lights may be used, the intent is to simulate the light that might occur under normal conditions in the filming space.

    The essence of naturalism in lighting is to ensure that the prevalent light on the location is “motivated,” that is, seeming to come from a logical source. Window light is a good example of a motivating source. Often a few household fixtures are placed in a scene as practical, either to actually supply light or to act as motivation for light from professional lighting units.

    The quality of fast lenses and film stocks has improved and it has become increasingly feasible to shoot film indoors entirely in available light, without bringing in any special lighting equipment. Feature filmmakers sometimes restrict themselves to available light in a scene to achieve a feeling of realism or perhaps to simulate a “documentary look.” For the documentary filmmaker, especially those making unscripted films, the decision of whether to use available light can be fundamental to the film. Since unscripted documentaries often involve intimate filming of family life, personal experiences and similar situations, there is usually a great premium on minimizing the disruption caused by the film crew. Bright lights can create an “on-the-set” feeling, and people under the lights often feel like they should perform. Also, since it is difficult to light an entire house or location, the use of lighting transforms some areas into filming spaces while others remain living space. All of this disrupts the natural flow of life that the filmmaker may hope to capture.

    Although some filmmakers argue that lights do not add significantly to the distraction caused by a film crew’s presence, especially in scenes that are inherently public, there is no question that the reliance on bright lights detracts from a crew’s mobility. Filmmakers who work primarily with available light have more freedom, carrying perhaps a few photofloods or screw-in quartz lights in case they need to film in very dark interiors. However, the use of larger lighting units may sometimes be needed at night or for large interiors.