About   |   Glossary   |   Site map   |   Help   |   Credits   |   Contact  Home   Color   Describing and Measuring Color   Color Rendering Index   Color Rendering Index The Color Rendering Index (CRI) describes the visual impact of light on colored surfaces. The CRI compares the effect of light emitted from any light source to the effect of light emitted from incandescent sources of the same color temperature and indicates the deviation of the color of the light source in comparison with that achieved by a true continuous spectrum incandescent light source.     Left - A scene lit by a 6 kW discharge fresnel. Right - the same scene lit by a 5 kW halogen fresnel spot. La Boheme, The New Israeli Opera. For example when a colored surface is illuminated by a fluorescent lamp with a correlated color temperature of 3,800O K, its color will appear different from its apparent color when it is illuminated by an incandescent source of the same color temperature. The CRI can vary between the values 0 and 1. A close match will be described by a high CRI while a poor match will be expressed by a low CRI . The color rendering index is of great  importance in the field of lighting for  television and photography. A fluorescent lamp (SP30) with a CCT of 3000K, and a CRI of 82.      An incandescent lamp of 3000K. For typical color rendering index (CRI) values for light sources.