The degree to which the light source appears to the color of the object is called color rendering, that is, the degree of color fidelity. The light source with high color rendering has better color reproduction. The color we see is closer to the natural primary color, and the color rendering is low. The light source's reproduction of the color is poor, and the color deviation we see is also large.

In principle, artificial light should be the same as natural light, so that the human eye can correctly distinguish the color of things, of course, depending on the location and purpose of the lighting.

The degree to which a light source is rendered for an object's color is called color rendering. Usually called the "color rendering index" (Ra).

Color rendering refers to the true color of a thing (its own color) and the color relationship displayed under a standard light source. The Ra value is determined by comparing the eight test colors defined in the DIN6169 standard with the standard light source and the tested light source. The smaller the color difference, the better the color rendering of the color of the measured light source.

A light source with a Ra value of 100 indicates that the color displayed by the object under its light is consistent with that under a standard light source.

In general use, the color temperature and color rendering index and brightness are mainly considered. The effects of the three objects on the irradiated object and the traditional lighting parameters are different. It needs to be matched according to the specific situation. In the future, LED lighting opens up the era of digital lighting。