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  Frequently Asked Questions - Lighting Education

How is quality of light determined?

Quality of light is determined by the relationship between the color temperature of the light, and the color rendering index.
The color temperature indicates the appearance created by the light source. The higher the color temperature, the "cooler" the color.
Typically, color temperatures of 2000K -3000K create a warm (yellow) appearance; above 4000K are cool (blue) in appearance. Between 3000K and 4000K are considered intermediate and tend to be preferred.
Color rendering index (CRI) rates a light source's ability to render colors in a natural way, based on a scale from 0 to 100. In general, light sources with high CRI (80-100) will make people and things look better than those with lower CRIs.

 
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