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by TigerhawkT3


1. What are "HID" and "metal halide"?


Q: What are "HID" and "metal halide"?
A: "HID" stands for High Intensity Discharge. It refers to a family of bulb technologies, such as low-pressure sodium, metal halide (MH), xenon short arc (XSA), and others. This family produces light neither by exciting electrons (LED) nor by heating a tungsten filament (incan), but by various other means. XSA, for example, contains two metal surfaces between which travels a spark of electricity, creating a tiny, intense ball of plasma. MH lamps operate in a mostly similar fashion, but require a ballast to regulate the conditions inside the lamp. Most HID lights used in flashlights (and by CPFers) are of the metal halide type, so the terms are often used interchangeably. MH lights are quite efficient, and their efficiency increases at higher power levels. At around 15-20W, they are about as efficient as modern LEDs. This creates huge output with very reasonable runtimes. MH lamps' CCTs vary from 3000K up to 20,000K.