Atmospheric effects on color
Colors do not just gray as they move away from the observer, they also change temperature, hue and saturation. You cannot get good color without paying attention to all these shifts.
Colors reside in a natural place on the value scale; this spot is where the color is at full saturation. If you look on most tubes of paint they will tell you what the value is for that color. If I look at the colors of my palette the values are , Ultramarine 2, Cobalt 3, Alizarin 2, Cad Red 5, Cad Yellow 7, Cad Lemon 8, and Titanium White 10.
As things move away from you they lose saturation and they cool, how much depends on the angle of light and the atmospheric condition and other variables but this is an observable phenomenon. The contrast between the lights and shadows also diminishes.
This does not mean cool colors recede. A blue box and orange box on a shelf both appear as close. Ruskin proved this idea 150 years ago but people still repeat the ‘everything is blue in the background idea’. The best way to dispel this notion of things turning blue is look at white and yellow as they recede. White shifts towards red and so does yellow.
So if you have similar colors in the foreground and the background, then background colors have to lose saturation and they also cool which means they move through the spectrum. Depending on their value they will also lighten or darken with great distance. This is observable with all colors when compared to similar colors in the foreground. So forget about pure color everywhere, that’s wrong. Pure saturation everywhere has the opposite effect; it flattens the space.
Instead instead of pure saturated color, focus on clean color and its relationship to similar colors in the scene. Clean color means a discernable color family in relation to other color families.
Remember compare lights to shadows for the overall effect; then compare shadow to shadow and lights to light within the effect to find chroma, temperature and value for the appropriate color note.