What is LED Fixtures?
Dimmable color-mixing fixtures using Light-Emitting Diodes represent a fairly new theatre technology. While in theory, they allow the designer to mix any conceiveable color, in practice this is limited by several factors, including the purity of the color produced by the LEDS as well as their relative lack of intensity.
Various manufacturers have chosen different approaches to the design of these fixtures; some use only the three primary colors, while others have as many as 7 different colors of LEDs in each fixture. LEDs are extremely efficient; one could conceiveably run an entire show from 2 or 3 wall outlets. They produce relatively little heat, as compared to conventional fixtures. It is possible to mix the visual equivalents of many commonly-used gel colors; a spreadsheet showing the settings for several of these, for use with the LED products made by Color Kinetics and Altman) can be found on Jeffrey E. Salzberg's web site.
LED fixtures are manufactured as wide-dispersal, "wall-wash" type architectural fixtures or as a more controllable, PAR-like instrument. The Altman SpectraPAR TM (as well as certain products by other manufacturers) is available in the same field sizes as conventional PAR64s.