Consider now the illumination of an

Consider now the illumination of an object with white light. If object reflects equal amount of all wavelengths, it will appear to the observer as white or some shade of grey. The greater the absorption, the darker the grey. An object which appears red when viewed in the same light has generally absorbed a predominance of the shorter wavelengths of the visile spectrum and reflected the remaining light into the eye of the observer. The absorbed light energy is usually remitted as heat. Thus, it is apparent that perception of colour in objects is totally dependent upon the way in which that object attenuates the light waves incident upon it. The relative absorptions of the various wavelengths determine its colour or hue, and the total absorption the lightness of that colour.