What does the CIE rating mean?
The C.I.E. (International Commission on Illumination) Publication 51 describes a standardized method to assess daylight simulator quality for colorimetry and color matching. The latest update from 1999 provides a rating system for the daylight simulators. The system is divided into two parts. The first indicates the quality of the source in the visible spectrum (400-700nm). The second indicates the source’s quality in the UV spectrum (300-400nm). An A/A rating is the best and an E/E rating is the worst. A rating of “B” in the visible spectrum will give between a 0.25 and 0.50 CIELAB Delta E visible difference, better than most people can observe. ASTM D1729-96, the standard for visual appraisal of colors and color differences, requires a rating of B/C for critical color differences and appraisal applications.
