There are a number of other circumstantial and environmental factors which impact how the eye perceives light and color. The intensity of the surrounding light changes the perceived color of any object.
Color temperature is a way of measuring the intensity of light radiating from a light source.
Color temperature is a measure of the relative intensity of all wavelengths in the visible spectrum. It is measured by comparison to a specific metal contained in a black box and heated to a specific temperature. The unit used to measure color temperature is Kelvins. The table in Figure 1-10 represents the approximate color temperature of different sources of light. The standard color temperature for viewing color reproductions is 5,000 Kelvins.