Fill light is used to eliminate or reduce shadows created by the key light in accordance with the narrative. If this lighting source to be used is a lighting source that gives hard light, as in the key light, or if the ratio of this source is equal to the key light, harsh or unwanted shadows will appear on the other side of the illuminated object.
A softer, second light source is needed to eliminate the harsh shadows created by the key light and to provide a natural expression. Fill lights usually consist of diffused and soft lighting sources.
The ideal spot for the fill light is thought to be just above the camera, but placing the illumination source this way can be difficult, so it is common practice to place the fill light on the opposite side of the camera and at roughly the same angle from the key light. Fill light minimizes shadows and helps reveal form, texture, and dimension in the object or space being viewed.
What does the fill light do?
- Sets the contrast ratio
- Creates depth and dimension
- Produces a more even lighting style
- Reveals the details and shapes of a subject
It should be noted that without light, there is no filming. Because video recorders do not give images without light in the design logic. Sometimes, the use of light can be used to create a shadow or to add depth to the emotion that the director wants to convey, with a different technique.