Each of the 12-Tones can be accurately mapped within colour space. When we do this we create what is known as a Colour Gamut. Sometimes it is helpful to ‘see’ where the hues sit in a Tone in order to understand that each one has identifiable and measurable parameters.
Image (a) allows us to see that the hues of the L Su Tone are found mostly on the cooler side of the colour gamut (between the red/blue/green points), rather than on the warmer side of the gamut (red/yellow/green). This is because the LSu tone is Cool/Neutral. If the Tone was warmer (as seen in the Light Spring) we would see more of the colours sitting between the red/yellow/green points of colour space.
Image (a)
The colours of the Light Summer Tone are medium to high/medium in Chroma. The closer the colours are to the center of the gamut the lower the Chroma, the closer they are to the outside, the higher the Chroma. If the hues of a tone are lower in Chroma (such as those found within the Soft Summer Tone) we would see more of the colours sitting closer to the centre of the circle (gamut). The opposite would be true for a higher Chroma Tone such as Bright Winter.
Image (b)
Image (b) shows us the Value of the LSu Tone. The horizontal line across the centre of the Gamut represents the mid point of the Value scale (light vs. darkness), with the black dot at the bottom of the axis the representing the lowest value point, and the white dot at the top representing the highest value. We can see that the majority of the L Su colours sit on the upper half of the horizontal line. This is because the predominant colour dimension of the L Su Tone is High Value or lightness of Hue.