a crucial part of painting that contain outside elements is atmospheric perspective. Shadow and light tones are affected differently as they recede but in a predicable manner. In both cases the hue shift is always to wards the color of the sky, in most cases this will be blue, but not always. In the shadows you will see big jumps in the hue of a color as it moves away from the viewer with relatively small changes in saturation. also shadow s will get lighter untill they approach the value of the sky itself.
Lights on the other hand will see a big change in saturation will relatively small changes in hue ( moving towards the color of the sky again) the value will move towards the value of the sky as well but in the case of lights it can get darker or lighter depending on the local color of the object. obviously the changes in value will be relatively small compared to the value changes in the shadows because it has less distance to travel to match the value of the sky. the changes in color of the lights is a direct mix of the main light source and secondary light source imposed on the object. so say the conditions are as follows.... the sky is yellow green and the main light source is orange-yellow. since both have a considerable amount of yellow in them objects with a local color of orange , yellow or gray will have considerable saturation as they recede compared to normal sunlight conditions (orange yellow main light and blue sky)