DIR Information Network | Lighting System FAQ

What is the difference between HID and Halogen lighting?

High Intensity Discharge (HID) lighting technology replaces the filament of the light bulb with a capsule of gas. The light is emitted from an arc discharge between two closely spaced electrodes hermetically sealed inside a small quartz glass tubular envelope capsule. To operate, they require ballasts, which supply proper voltage and control current. The amount of light produced is greater than a standard halogen bulb, while consuming less power, and more closely approximating the color temperature of natural daylight.

HID lighting has several advantages over conventional halogen primary lights:

• More light output. Halcyon's 18 Watt HID light source produces approximately the same lumens at the light source as a 55 Watt halogen bulb at a three to five times the halogen's efficiency. The 10 Watt HID only produces ~500 lumens, but thanks to its true 6000K color temperature it appears almost as bright as a 55 Watt halogen bulb when in use. The HID lamp's lumens per watt (LPW) efficacy is roughly six to eight times that of an incandescent lamp.

• Whiter light. The color temperature of HID lighting more closely approximates the color temperature of natural daylight than does a halogen system, which appears yellowish in comparison. We use the term "correlated color temperature" to indicate that the light appears as if the discharge lamp is operating at a given color temperature-- traditional measurements of color temperature are drawn from the properties of the metal used in the bulb's filament. Typical color temperatures are 2800K (incandescent), 3000K (halogen), 4100K (cool white or SP41 fluorescent), and 5000K (daylight-simulating fluorescent colors). Both of the Halcyon HID lights produce a light with a color temperature approaching or above 5000K. A white light has a perceived brightness which may equate to the higher stated efficacies-- ie., although an HID lamp might have equivilant lumens as a higher wattage halogen bulb, the HID will appear brighter to the eye.

• Longer Service Life. An HID lamp will last, on the average, 3 to 5 times as long as a halogen bulb. In normal use, your Halcyon HID bulb should last beyond one thousand ignitions.

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