RGB/CMY Hue System
Bendito's Master thesis 'Perceptual Analysis of the RGB Color Cube' has led to the development of a perceptual notation system. This notation has been greatly influenced by the works of Munsell, Birren, and Ostwald.
Notation Structure
The primary and secondary colors are represented by the beginning letter of their name:
Notation Structure
The primary and secondary colors are represented by the beginning letter of their name:
R = Red
B = Blue
G = Green
M = Magenta
C = Cyan
Y = Yellow
Tertiary colors are made from a combination of primary and secondary colors. The notation for the tertiary color is the combination of the two beginning letters of the colors they are made of. For example, Red (R) and Yellow (Y) produces the tertiary Red-Yellow.
The Red-Yellow is subdivided into five color steps which are labeled Ry, RY, RY, YR, Yr. The upper and lowercase letter are used to represent the level of perceptual predominance of either a primary or secondary color. The capital letter indicates the predominant color:
The Red-Yellow is subdivided into five color steps which are labeled Ry, RY, RY, YR, Yr. The upper and lowercase letter are used to represent the level of perceptual predominance of either a primary or secondary color. The capital letter indicates the predominant color:
Ry = Mostly red, a little yellow
RY = Almost even, more red
RY = Even amount of red and yellow
YR = Almost even, more yellow
Yr = Mostly yellow, a little red
Note: The RY colors do not appear in the RGB3 Color Wheel.
Expanded RGB3 Notation System
The colors of the RGB color cube can be mapped within consistent patterns related to a gray scale and to the level of purity of the color as shown below:
The colors of the RGB color cube can be mapped within consistent patterns related to a gray scale and to the level of purity of the color as shown below:
The RGB3 gray scale has 6 even steps from black to white. The intensity of a color increases from left to right towards its pure state.
Each color can be mapped according to the family it belongs to (i.e. red, blue...), its relation to the gray scale, and its level of intensity.
Each color can be mapped according to the family it belongs to (i.e. red, blue...), its relation to the gray scale, and its level of intensity.
For example the notation Y 8/4 means:
- Y = This color is yellow (Y)
- 8 = This is the location of this color in relation to the gray scale.
- 4 = This is the level of intensity. Color has low intensity.
- Y = This color is yellow (Y)
- 5 = This is the location of this color in relation to the gray scale.
- 10 = This is the level of intensity. Color has high intensity.

Note: Compare the three notation system below. The perceptual notation (PN) system has the potential to pinpoint the color family, its relationship to the gray scale, and its level of purity (intensity).
PN Notation Limitations
This notation system has been applied only to the web color lookup table (also known as the web safe colors) which is composed of 216 colors sampled from the RGB Color Cube.
This notation system has been applied only to the web color lookup table (also known as the web safe colors) which is composed of 216 colors sampled from the RGB Color Cube.