You've probably seen a dark horror film, a well-lit romantic comedy, and a grim and gritty war movie. Digital effects are sometimes used to colorize the film during post-production, but what gives each of these types of films its unique look and feel is the knowledge of how to light a scene and the type of lighting used on location. There has always been a give-and-take relationship between lighting techniques and film genres. For example, filmmakers often portray villains that are heavily shadowed using silhouettes to impart a dreary feel.

Initially, many types of lighting units were developed for non-filmic uses, such as street lighting or searchlights. Only later was their potential for producing cinematic lighting effects explored. The history of film lighting is a complex chronicle of intersecting influences. The lighting techniques used in the early cinema of the late 1890s and the first years of the twentieth century were astonishingly primitive in comparison with the recent times. Filmmakers of that era relied almost entirely on bright daylight. For this reason, when films were not shot on location they were filmed on rooftop sets, or else in studios built with either an open air design or a glass roof. The use of daylight as the main source of illumination provided visual clarity. It did not allow as many opportunities to create dramatic effects as artificial lighting did, however. Nor did it permit indoor or night-time cinematography. The first uses of artificial lighting have been traced back as far as 1896, when the pioneering German filmmaker Oskar Messter (1866-1943) opened his indoor studio in Berlin. Although the use of artificial lighting was initially confined to replacing or augmenting sunlight in order to provide a clear image, by 1905 filmmakers had begun to explore the creative possibilities of artificial light.

Various lighting techniques
The range of lighting sources that were used in film, and a growing appreciation of their potential to create specific effects, encouraged the development of more sophisticated lighting styles.

Three-point lighting system

One of the best-known lighting setups is the so-called three-point system, which was used primarily for figure lighting. It uses a key light, a fill light, and a back light (or rim light). Using three lights from three different directions creates a sense of depth on people and objects guaranteeing everything will look three dimensional.

1) The Key Light - The key light is the primary light used to illuminate a subject. It is usually positioned 15 - 45 degrees from one side of the camera and angled down 15 - 45 degrees from above the subject. This light represents the primary source of light in a scene simulating the sun, a window, a light bulb or some other source of light.

2) The Fill Light - After the key light is positioned you will notice a harsh shadow on one side of the subject opposite the key light. The fill light is meant to reduce the shadow but not eliminate it entirely (shadow gives a sense of depth). A fill light should be placed on the opposite side of the key light but needs to be about half as bright and not positioned quite as high. Do not place it at the exact same angle as the key light. It is meant to simulate other light sources or light that is being reflected off other objects.

3) The Back Light - The back light needs to be placed behind the subject opposite the camera but high above both so that none of the light goes directly into the camera. This light will create a slight glow on the back of the subject and thus separate it from the background. This prevents the subject from looking two dimensional on the film. It is sometimes referred to as the hallo effect.

High-Key Lighting

A lighting scheme in which the fill light is raised to almost the same level as the key light. This produces images that are usually very bright and that feature few shadows on the principal subjects. This bright image is characteristic of entertainment genres such as musicals and comedies

Low-Key Lighting

A lighting scheme that employs very little fill light, creating strong contrasts between the brightest and darkest parts of an image and often creating strong shadows that obscure parts of the principal subjects. This lighting scheme is often associated with "hard-boiled" or suspense genres such as film noir.

Four-point lighting system

The addition of a fourth light, the background light, makes for a four-point lighting setup. The background light is placed behind the subject(s), on a high grid, or low to the ground. Unlike the other three lights, which illuminate foreground elements like actors and props, it illuminates background elements, such as walls or outdoor scenery. This technique can be used to eliminate shadows cast by foreground elements onto the background, or to draw more attention to the background. It also helps to off-set the single eye nature of the camera, this means that it helps the camera give depth to the subject.

Beyond Four-Point Lighting

Of course there are many variations to this scheme and additional lights are often added as needed, but for 95% of your movie making, this simple schematic will do. Once you have mastered this technique and are able to create and sustain a general mood throughout a movie, feel free to experiment as much as you like. However, until you do, don't start playing around too much or you could ruin an otherwise good movie with poor lighting.

Film Noir Lighting

Regarded as one of Hollywood's eminent cinematographers, John Alton was the pioneer of film noir style of lighting in cinema. His contribution to more than a dozen noirs helped to define their characteristic style of high-contrast black-and-white cinematography. In Bollywood it was Guru Dutt who inherited the traits of the film noir - created by John Alton. For example the use of low-key lit, sharp angular shooting style of the noir and the dolly-ins to close-ups were evidently seen in films like Baazi, Pyaasa and his masterpiece, Kaagaz Ke Phool. Dutt, thus, in the process, became one of the founders of what can be known as the Bolly-Noir, of the 1950s.

Exercise

Now, since we have tipped you enough with the various styles of lighting techniques, you are definitely in the position to light a scene of your own. Here's a small exercise for you to see whether you have understood the way it needs to be done.

The day's shot list calls for bikini-clad teens to sneak into the neighbour's pool in the middle of the night. In one scene, the teens are standing around the edge of the pool talking, and you really want some of that great wavering, shimmering light that comes from the pool's underwater lights or reflects from other lighting. Unfortunately, the natural lighting isn't throwing light in the right places, and you're not getting a bright enough read from it anyway. How will you simulate that great reflective shimmer on your actors or the wall behind them?