Analysis of the Applicability of Different Color Difference Equations in Printing Industry

Pages:74-79
Dinesh C. (Service Engineer, Creation Offset Press, Ernakulam)

The first color difference equation is developed by CIE (International commission On Illumination) on 1976 known as Delta E 76 or Delta E ab. Here the attributes of colors such as chroma, hue and lightness are considered in equal value or importance. That is perceptibly not suitable to the human eye. Changes in hue can easily identifiable than the changes in lightness. The color measurement committee of the society of Dyers and Colorists of Great Britain developed a new color difference equation based on the weightage for lightness and chroma difference. In 1995, CIE developed Delta E 94 where hue, chroma and lightness are specially considered by giving weightage and it gives better results. Finally most accurate color difference equation Delta E00 introduced which corrects inaccuracy in the calculation of lightness in Delta E94. This paper shows the Delta E ab or E 76 higher color differences than the other Delta E equation based color differences. The variation in Delta E 94 and Delta E 00 is very less due to the inaccurate calculation of lightness in Delta E 94. Delta E CMC l:c shows good acceptability based on the human visual perception and used in the textile industries. The ISO technical committee TC 130 accepted the Delta E2000 for color difference analysis for ISO 12647 based offset printing. Delta E 2000 will be the new industry standard by replacing the Delta E ab for color difference analysis.