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Light Bulb Color Temperature

Light Bulb Color Temperature

Many people are familiar with "cool" white or "warm" white fluorescent light bulbs. These bulbs have vastly different color temperatures. A "cool" white bulb commonly has a color temperature of 4,100K. This is in the low range of blue color, similar to ice. Hence, the "cool" adjective.

The "warm" fluorescent bulb often has a color temperature of 3,000K. It imparts a more orange / red light on objects. Because you normally associate warmth with red or orange objects, this accounts for the "warm" descriptive name, even though it is a cooler temperature on the Kelvin scale.

As we discussed in photography, color temperature can affect the way things look in your house. If you decorate with reds, browns, and oranges, you want to illuminate these rooms with bulbs that have a color temperature in the 2,750 - 3,000K range. Conversely, if you happen to like green carpets, or blue colors, light these rooms with bulbs that produce color temperatures of 4,000K or above.

What happens if you have both colors in a room? No problem! Use a mid range bulb. You can purchase bulbs that produce light in the 3,500K range.

Color Rendition

This color thing gets even more confusing. Don't blame me! I'm trying my best to make sense out of it.

Two different bulbs that have the same color temperature can produce vastly different looks on colored objects. In other words, an inferior or poor quality bulb can make a red object actually appear green! I'm not kidding! As such, light scientists developed a way to measure the ability of a bulb to render true coloration. They use a color rendering index. It is simply a scale of 0 to 100. The closer a bulb is to 100, the better job it does at rendering true colors.

When you purchase bulbs from a lighting store, they normally have this information in their catalogues. I doubt that you can easily obtain this information from a giant home center store that has hundreds of light bulbs on their shelves.

It is really worth it to visit a full blown lighting center. Ask the sales people what they know about color temperature. Ask for literature. The major bulb manufacturers have GREAT booklets on this subject with dramatic photography showing just what can go wrong.

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