Cross-section of the HSV Hexcone:

Saturation S varies from 0 to 1. This is represented in this model as the ratio of the purity of a selected hue to its maximum purity at S = 1. A selected hue is said to be one-quarter pure at the value S = 0.25. At S = 0, we contain the gray scale. Value V varies from 0 at apex of the hexcone to 1 at the top. The apex represents black. At the top of the hexcone, colours contain their maximum intensity. While V = 1 and S = 1, we have the "True" hues. White is the point at V = 1 and S = 0.

It is a more intuitive model for most users. Beginning with a selection for a pure hue, which specifies the hue angle H and sets V = S = 1, we explained the colour we want in terms of adding either white or black to the pure hue. Adding black reduce the setting for V while S is held constant. To obtain a dark blue, V could be set to 0.4 with S = 1 and H = 240°. Likewise, when white is to be added to the hue selected, parameter S is decreased while keeping V constant. A light blue should be designated with S = 0.3 while V = 1 and H = 240°. By adding some black and some white, we decrease both V and S. An interface for this model typically presents the HSV parameter choices in any colour palette.