What material is used to produce color effects in lighting by placing a thin sheet over the light?

The material used to produce color effects in lighting is a gel. Gels are thin sheets of colored plastic that are placed over light sources to alter the color of the light emitted. This technique is commonly used in video production and theater to achieve specific moods, enhance scenery, or create visual effects that support the narrative.

Using gels allows filmmakers to manipulate the illumination in a scene creatively, helping to set the tone or highlight certain elements within the frame. The flexibility and variety of colors available in gels make them a staple in lighting design.

In contrast, diffusers are used to soften the quality of light, filters can modify light properties but are generally not used primarily for color effects in this context, and reflectors are employed to redirect light rather than change its color. Each of these tools serves different purposes in lighting setups, emphasizing the unique role of gels in producing color effects.