From the Wikipedia page on the RGB color model -> Numeric representations:
A color in the RGB color model is described by indicating how much of each of the red, green, and blue is included. The color is expressed as an RGB triplet (r,g,b), each component of which can vary from zero to a defined maximum value. If all the components are at zero the result is black; if all are at maximum, the result is the brightest representable white.
What exactly is each step in one channel/color? What does it increase? Luma? Intensity? Saturation? Chroma? Chrominance?
I honestly don’t understand Luma, Chroma and Chrominance well enough to explain why it is or isn’t increased by adding to one or more of the channels. It might increase them, or it might not. I wouldn’t know.
It definetly does NOT increase saturation. If we start at (0, 0, 0) and add the same ammount to all channels, the saturation stays zero.
However, adding to a channel increases Brightness.
This is intuitively true, given that the color component on a screen shines brighter for higher values.
It is also well defined, that is,
brightness = (R+G+B)/3
Source : Link , Question Author : Dan Dascalescu , Answer Author : Kjeld Schmidt