Humans perceive color when light interacts with objects using photoreceptors in the eye, primarily through the processes of transmission or reflection. Color measurements using UV-Vis spectrophotometers use the same principle as the human eye. However, UV-Vis spectrophotometers can objectively obtain a value that describes the color by offsetting the color of light used to illuminate the sample. The best choice of instrument for a particular application will depend on sample type and analysis requirements. This white paper describes the options for color measurements that are available from Agilent, including an overview of the Cary WinUV Color application that translates spectral data according to various geometrical coordinates and illumination systems.