The perception of color relies on three elements: the light source, object and observer. From a scientific viewpoint, an object does not have inherent color. The perception of color is created solely by the reflection of light from an object."
I would like to add another component besides "light source", "object" & "observer", and that is "environment". Because other color objects that are in the surrounding also reflect their light(color light), and these different light will to a certain extent affect the color of the object we see.
Blue objects absorb great amount of red light and reflect blue light. If you see a red object with a high intensity white light shining directly on its surface, of course you see red as red; Red object reflects red light. But if the other side of the red object is in a shade, not directly shined by the white light, then its red color will be affected by the surrounding color light reflected by other objects. In this case, if there is a blue object besides it, then the blue light will shine on the red object, resulting in it looking purplish in color!
A large part of the environment we live in is in shade. We don't really see everything in direct lighting, like what we see in a photo studio where various lighting are pointing at the subject from different angles. Especially, you can witness very vibrant photos of models; All colors are in maximum saturation. This is due to the various artificial lighting shining at the model from different angles, which is not possible in a normal & mundane environment of our everyday lives.
Let's say, if you shoot your model in a park where there is a lot of greenery. With today's digital technology, you won't have to worry about your model looking green in color due to color cast. Especially, if the model is dressed in white clothes, you will see green instead. But those who shoot in film will have to worry about casting, they will normally attach a magenta colored filter to counteract the green color.
Sometime, you can see a slightly magenta color cast on actors/actresses' skin in a TV serial, if you are discerning enough. When you can notice it, you know they have used a magenta filter to counteract the green light; In such case, the scene of the shooting is definitely in a park or where there is a lot of greenery in the surrounding.
