One of the most fundamental issues of Photography and Painting is the color and the combination of colors. The difference is that, while the artist can freely create his own color, the photographer can only choose the colors available to include in the image.
A painter can master color by blending colors, he has a certain taste in color and an unlimited number of tones. In photography, colors existed before we took the shot. What we can record on the film/sensor is the debris separated from the total color of nature. The number of colors is infinite in nature, but photography cannot mix them and create new colors like a painting.
The concept of primary colors (the primary colors to create other colors) has a long history and often starts with the pure pigments found in nature. Up to now, it has been unified in two different systems, the direct light system has three basic colors: Red-Blue-Green and the reflected light system has 3 other basic colors: Red-Yellow-Blue.
Saturation: The primary colors are completely saturated then it gives maximum color intensity. In fact, in life, colors are rarely completely saturated. Therefore, the primary colors are always used as the focus of a picture if we find them in nature. In practice one can reduce the saturation of a color by adding white, black, gray or an additional color. In fact, it is rare to find completely saturated colors in nature, apart from the flowers and some animal pigments, even the unsaturated blue sky as we perceive it.
Luminate: The maximum light intensity depends on the color. Yellow is the lightest and darkest purple. Brightness makes colors light up or darken. White and black are 2 extremes. The intensity of light in photography depends on the exposure). By changing it, you will get different color effects.
Color of the objects: The things around us have no color. When light waves hit an object, it depends on the properties of the material to have different effects. Light waves can be absorbed or reflected by objects (depending on their composition).