Accuracy of color measurement by using digital cameras and the standard color chart

Abstract

We examined five different digital cameras and evaluated their accuracies of color measurement. Commercially available digital cameras are not intended for use in color measurement. Thus, users have to calibrate the camera system by themselves for the purpose. We adopted the image correction method, in which, samples are photographed with some standard color charts side by side in one photo and the photographed images are color-corrected using the colorimetric data of the color charts. This method has an advantage that the measurement accuracy does not depend on the camera used; Users can freely replace the cameras. Using the X-rite ColorChecker 24-color chart as standard colors, we examined how the accuracy of color measurement depends on the camera used. As a result, we showed that the expected accuracy is less than 5 in the CIE L*a*b* color difference unit within the color gamut of the standard colors, irrespective of the camera.