Measures of saturation at threshold and suprathreshold levels were studied for wavelengths between 460-650 nm and at approximately a constant luminance (29 +/- 5 cd/m(2)). The suprathreshold functions, obtained by magnitude estimation, are distinguishable by their lower exponents from those of the monocular functions. This effect is probably related to a strategy of the cortex for the unification of signals. The reiteration of the saturation measures observed through our own data and those of other authors represent a reliable source for the analysis of the chromatic vision, both at the retinal as well as the cortical level. (C) 2000 John Wiley & Sons, Inc. Col Res Appl, 26, S53-S56, 2001.