Spotlight (theatre lighting)
A spotlight, sometimes known as a followspot, is a powerful stage lighting instrument which projects a bright beam of light onto a performance space. Spotlights are controlled by a spotlight operator who tracks actors around the stage. Spotlights are most commonly used in concerts, musicals and large scale presentations where highlighting a specific, mobile, individual is critical. Spotlights are sometimes located overhead on catwalks. In some theatres, they may also be located in the control booth or purposely built "spot booths" in addition to the catwalk. Spotlights may be arranged in a variety of patterns for coverage. For example, they are aimed at the stage in front of them in theaters, located to the back or rear. This location can become problematic due to fan noise or any communication by headset communication from the spot operator speaking into his headset microphone. In circus and sports, spotlights may be arranged around the facility covering both sides and the ends. In a concert setting, they may be in a position Front of House (FOH), while other positions may have the spotlight upstage used as back or top light. Some concerts use truss spots on a truss downstage but closer than catwalk spots in an amphitheater style catwalk layout. In other places, spot locations are at the mercy of the architect who designed the space.
Characteristics of a typical spotlight include:
- A strong light source, often a high-intensity discharge lamp with a high colour temperature.
- A lens which can be manually focused.
- A manual device to change the intensity of the beam, especially when an HID source which can not be electronically dimmed, is used.
- An "iris" to adjust the size of the spot/angle of the beam.
- A color magazine or "boomerang" consisting of several gel frames which can be swung in front of the beam.
- Some sort of physical sight to assist in aiming is sometimes added onto the lamp by the operator.
Perhaps the best known brand of spotlight is the Super Trouper by Strong Entertainment Lighting, as made famous by the ABBA song of the same name. Other well known spotlights include the Altspot line by Altman Lighting and Aramis and Ivanhoe lines by Robert Juliat.
The optics of a spotlight