HOW to calculate the Color Rendering Capacity ?
* The key to calculating the color
rendering capacity of a given spectral power distribution is to
calculate the volume of the color solid correspondinr to the given spectral power distribution.
Suppose the calculation is conducted in the CIE 1976 u*v*L* color space..
* Using the spectral reflectance curves of special type that consist of either one single reflecting
band or one single absorbing band with the values of spectral reflectance being either 0.0 or 1.0,
in conjunction with the given spectral power distribution , a group of chromaticity coordinates
(u*v*) can be calculated for one specified value of L* .
* A polygon can be constructed with this group of chromaticity coordinates (u*v*) for the
specified value of L*. And the area of the polygon can be calculated.
* The sum of those areas of the 9 polygons associated respectively with L*=10,20,...,and 90 comes
, approximately, to the volume of the color solid corresponding to the given spectral power
* A software CRC99 has been available for calculating the Color Rendering Capacity of any
kind of light sources.
Download a simplified version
of CRC99 to calculate the
color rendering capacity of any light source: CLICK HERE
1 Download the file Crc99.zip (18KB) to drive C:
2 Extract the file to folder C:\Crc99\
3 Run C:\Crc99\Crc99.exe, that is all.
A printout of CRC99 calculation results: