Cyc Lights

What is a cyc light

Cyc lights are floodlights designed to create a soft and uniform spread of light onto a cyclorama for background illumination. Cyc is short for cyclorama. A cyclorama is a large stage curtain made of canvas, muslin, or other material. It is usually hung in a U-shape drape and located at the farthest upstage. Sometimes a cyclorama can be a plaster-finished upstage wall. Cycloramas are designed to mask backstage areas of a stage from spectators and serve as a backdrop which may be plain in order to project light and/or images onto it or painted with a decorative or pictorial scene to fit a specific show. Cyc lights are installed overhead and/or free standing on the stage floor and throw evenly distributed wash of light from up where they’re hung all the way to the floor and/or from the floor to the ceiling. There are two types of cyc lights: linear striplights and asymmetrical floodlights. Striplights are versatile fixtures that can be used as cyc lights, borderlights and footlights. Asymmetrical floodlights have been developed specifically for cyc lighting.

Light distribution requirements

Homogeneous illuminance distribution is a critical design requirement for cyc lighting. Striplights are typically direct lighting systems which may produce a scalloping pattern or hotspots on the cyclorama when the luminaires are rigged near the vertical surface. Asymmetrical floodlights make use of light reflecting off an asymmetrical reflector to achieve an even spread of light. This optical system results in photometric distributions generally comparable to those of perfectly diffuse emitters, with the additional advantage of creating a more controllable beam pattern. Asymmetrical floodlights are more suited to illumination of tall cycloramas owing to their ability to distribute high uniformity light across a long distance.

Color alteration

Traditional cyc lights use filament lamps which are not only electrically and optically inefficient, but also require the use of filters to alter the color of light when a colored effect is desired. Within the stage lighting industry, LED technology has become a game-changer and is driving the development of new lighting concepts and applications. Cyc lights, with no exception, have an accelerating adoption of LED technology.

LED cyc lights provide color changing lighting in a breeze

An LED cyc light has an integrated light engine that can be configured to deliver a variety of design options in both function and form. The LED technology platform allows to engineer the spectral power distribution (SPD) of a lighting system at the chip-, package-, and/or module-level without using color filters. Beyond providing basic white or single-color illumination with the LEDs mounted on a simple switched or dimmed circuit, LED cyc lights can be designed to provide tunable white lighting or additive color mixing for a full spectrum of colors. These systems use multiple groups of LEDs with each group controlled by a dedicated circuit.

LED driving and dimming

A multi-channel LED driver is used to control individually the LED channels. More sophisticated digital cyc lights use addressable LEDs to deliver different color effects and dynamic patterns across the light emitting surface (LES) of a single luminaire. Dimming of the LEDs are usually accomplished through pulse width modulation (PWM). The light fixture communicates with a lighting controller using the DMX512 protocol. The LED drivers are typically designed as switching power supplies in order to provide tight line and load regulation for the LEDs.