Colour concepts:

Colour concepts linked with the terms shades, tints, and tones are represented in across-sectional plane of the HSV hexcone . Adding up black to a pure hue reduced V down the side of the hexcone. Therefore, various shades are represented with

values S = 1 and 0 ≤ V ≤ l. Adding up white to a pure tone produces different tints across the top plane of the hexcone, where parameter values are S = 1 and 0 ≤ V ≤ l. Several tones are specified by adding up both black and white, generating colour points within the triangular cross-sectional area of the hexcone.

The human eye may distinguish about 128 different hues and around 130 different tints (saturation levels). For each of these, a number of shades (value settings) may be detected, based on the hue selected. About 23 shades are discernible with yellow colours, and around 16 different shades may be seen at the blue end of the spectrum. It means that we may distinguish around 128 × 130 × 23 = 82,720 different colours. For most of graphics applications, 128 hues, 8 saturation levels, and 15 value settings are sufficient. With this range of parameters in the HSV colour model, 16,384 colours would be available to a user, and the system would need 14 bits of colour storage per pixel. Colour lookup tables would be utilized to reduce the storage requirements per pixel and to enhance the number of available colours.