Lighting is a vitally important element of filmmaking and is a quintessential technique in evoking a specific style. The three core types of lighting are key, fill and, backlighting – each serving a different purpose which is explained below.
Types of lighting
Key Lighting
The key light acts as the primary light source of a scene, usually being the strongest light on the set. The key light can be placed anywhere to create a number of different effects, but it is recommended to avoid placing it near the camera.
There are two main types of key lighting, being high key and low key. High key lighting refers to a style of lighting that displays an extremely bright scene, with no shadows present. Conversely, low key lighting contains lots of shadows and perhaps only one strong key light source.
Fill Lighting
Fill lighting is used to ‘fill in’ any unwanted shadowy areas that the key light creates. Noticeably weaker than the key light, the fill light is usually placed in the opposite direction to the key light.
Backlighting
Backlighting completes the third dimension of a scene, usually facing the primary subject of the scene. Once again, the backlight is considerably less intense than the key light. In effect, a backlight accentuates the silhouette of a subject.
Otis Morley’s A-Level Film Studies Blog 