How to distinguish lightness from nine tones

1. Firstly, the lightness is divided into nine lightness zones from deep to shallow, which are low lightness zone, medium lightness zone and high lightness zone.

2. Then within the three color differences, it is divided into weak contrast, medium contrast and strong contrast.

3. Finally, nine light tones can be obtained, including low short tone, low alto, low long tone, medium short tone, medium alto, medium long tone, high short tone, high middle tone and high long tone.