Lamps and Lighting

Cruising down Main St. after dark, you notice how different various signs appear, but you may not be aware that these variations have as much to do with the lighting source as they do with the color and type of translucent material. Lamp coloration is a vital component of the illuminated image. Not surprisingly, sign specifiers are quite particular about the lamp characteristics they select for major identity programs. Specifications vary depending on the lighting effect the customer desires. Some users prefer a warmer, "soft and fuzzy" image, while others choose the cool, clinical, "corporate" look. The terms "warm" and "cool" describe the first major color characteristic of light – color temperature. The color temperature scale for lighting (see accompanying figure) is based on the color assumed by a piece of metal (technically called a "blackbody radiator") when heated to a given number of Kelvin (K) degrees. These colors correspond to the full spectrum of natural light, ranging from orange/red at the cool end of the scale to blue/white at the hot end. Confusion arises because a lamp that appears "warm" emits light registering at the cool end of the color temperature scale. By contrast, "cooler" lamp colors register higher on the scale. This is because the "warm" and "cool" designations refer to the subjective way in which humans perceive these colors and their psychological effect, not the color temperature.