What is the primary purpose of using colored gels in stage lighting?

The primary purpose of using colored gels in stage lighting is to change the color of light. Gels are transparent colored materials placed in front of light sources to alter the hue of the emitted light. This allows lighting designers to create specific moods or atmospheres that enhance the visual storytelling of a production. By adjusting the color of the light, gels can evoke certain emotions, highlight specific areas of the stage, and help define the environment in which the characters exist.

While colored gels can indirectly contribute to enhancing an actor's visibility and can be used creatively to achieve special effects, their main function is focused on modifying the color itself. Sound filtering doesn't relate to the use of colored gels in lighting design, making it irrelevant in this context.