The article "Color Error Analysis of Standard Swatches Under Different Light Sources" by Ying Chaofu, a scholar from Zhejiang Normal University, mainly expounds the conversion of chromaticity coordinates under different light sources by using standard swatches as samples, and gives the results of different light sources. The color error of the standard swatch.
Because objects have the properties of selective absorption and selective reflection for spectral components, different objects will show different colors under the same light source. In addition, the color of the object is closely related to the light source. The same object is illuminated by different light sources. Due to the different spectral power distribution of the light source, the color of the object will also be different. In order to quantitatively analyze the color error of objects under different lighting sources, the author uses the photographic standard color plate (white plate) developed by the Chinese Academy of Metrology as a sample to calculate its color difference under standard light sources A and D 65 and bromine tungsten lamp illumination.
In the whole research process, the chromaticity coordinates of the light source were analyzed first, then the chromaticity coordinates of the standard color palette under different light sources were calculated, and finally the color difference of the standard color palette under different light sources was calculated.
Conclusion: To sum up, due to the difference in spectral power distribution of different light sources, the color of the same object will be different under different light sources. Of course, the size of the color difference depends on whether the selection of the color difference formula is consistent with the subjective evaluation of people [3～4 ] and other factors. The tolerance of human beings to the size of the color difference depends on the specific application situation and the sensitivity and preference of the observer to the color. As for the range of the color difference of the object that should be allowed to be considered appropriate, it depends on the specific situation. In the CIE1964W*U*V* uniform chromaticity space, for paints and textiles, a slight difference in color is more obvious, and the allowable color difference should be controlled within a few NBS units, but the reproduction of the typical color of color TV, the average color difference If it is controlled within 10 NBS units, it is considered that a satisfactory reproduction effect has been achieved.
It can be seen from the calculation results that the color error of the standard color palette under different light sources is within 5 NBS, and such a difference is generally invisible to our human eyes.
