A measure of saturation can be obtained with the help of the following experiment. A achromatic color is taken. For each wavelength, the pure hue is added to this color, until the hue is detectable to a human observer. The results are shown in Figure 2 .Obviously, substantial amount of differences exist in our capacity to detect different hues. Thus, saturation depends upon the relative dominance of pure hue in a color sample.
Saturation decreases if the band of wavelengths in a color is increased.
It also decreases if the amount of neutral color added to the pure hue is increased Saturation also depends on the wavelength of the pure hue. For example, yellow always appears desaturated and the rate of decrease of saturation is also larger.