Colour Checker Chart
The ColorChecker Classic Card from X-Rite is a checkerboard array of 24 scientifically prepared coloured squares. The colours of these squares represent natural objects such as human skin, foliage, and blue sky. These squares are not only the same colour as their counterparts, but also reflect light the same way in all parts of the visible spectrum. Because of this unique feature, the squares will match the colours of natural objects under any illumination and with any colour reproduction process.
This makes the ColorChecker a non-subjective standard of comparison to help determine the true colour balance of any colour rendition system, and it provides the needed standard for comparing, measuring and analyzing differences in colour reproduction in various processes.