Stage lighting accessories

Stage lighting accessories are components manufactured for conventional (non-automated) stage lighting instruments. Most conventional fixtures are designed to accept a number of different accessories designed to assist in the modification of the output. These accessories are intended to either provide relatively common functionality not originally provided in a fixture (such as beam shaping through barn doors), or to extend the versatility of a lighting instrument by introducing features. Other accessories have been designed to overcome limitations or difficulties some fixtures present in specific applications.

All stage lighting accessories fall into one of three distinct categories: components installed inside the fixture, components affixed to the front of the fixture (in front of the lens), or components mounted elsewhere on the exterior of a fixture (to the side, top or bottom).

Barn doors, or occasionally a set of barn doors, are an attachment fitted to the front of a Fresnel lantern, a type of lantern used in films, television, and theatres. The attachment has the appearance of a large set of barn doors, but in fact there are four leaves, two larger and widening on the outside, two smaller and getting narrower towards the outside. They facilitate shaping of the beam of light from the fixture, and prevent the distinctive scatter of light created by the Fresnel lens from spilling into areas where it is not wanted, such as the eyes of audience members.

Barn doors are mounted with a ring that fits inside of the color gel slot on the instrument. Because of this, barn doors have a gel slot built into them, so the light can still be colored. Depending on the size and local practices, barn doors may be attached to the pipe or the instrument with their own safety cable.

Barn doors are generally not used with "profile" or "ellipsoidal reflector" spotlights such as the Source Four because they have internal shutters which work more effectively. Barn doors are not effective at shaping the light of a PAR lights and a narrower lens would be a better way to do this.

A top hat, also known as a stove pipe or snoot, is a device used in theatrical lighting to shield the audience's eyes from the direct source of the light. It is shaped like a top hat with a hole in the top, and the brim being inserted into the gel frame holder on a lighting instrument. The cylinder allows light to pass through but takes away the glint of a lighting instrument facing the audience. It also reduces flare created by the light, which is often useful when the unit is hung near the proscenium or other objects that the designer does not want to light. There are also half-hats or "eyelashes", which function in a similar manner but have only half the cylinder, and short hats, which are shorter in length. Top hats are manufactured for most modern-day lighting instruments with gel frames of varying sizes.

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