Tone in photoshop cs (noun explanation)

Hue is actually its own color feature, which is manifested in the warmth and coldness of color and the psychological feelings it can cause. It is the most fundamental feature of color, which is ultimately determined by the wavelength of light. Brightness is determined by the energy intensity of light, and purity is determined by the amount (proportion) of a single color. The more colors are mixed, the lower the purity. The mixing lightness of color and light will increase, because the total energy value will increase, and the three primary colors (red, green and blue) will be mixed into white, which is called additive three primary colors. The brightness of the pigment mixture will decrease, and the mixture of three colors (red, yellow and blue) or complementary colors will turn black in theory, but in fact it will only become dark gray. Because the absorption spectrum is wide and the reflection is less, it is called subtractive tricolor. In addition, you will find that although there are red and blue in addition and subtraction, their red and red are different, and so are blue and blue. For example, if you add a color: red+green = yellow, you will get a brighter yellow than red and green. The subtractive method blue+yellow = green, which is darker than blue and yellow. So you will find that the green in RGB is brighter and brighter than the green in CMYK. Color elements basically make you understand.