The only thing a painter can paint is the light. It seems like he's painting a tree or a face, but he's painting the look of the light that is bouncing off the object and landing on the retina. The subject is the light. Even if it's in the shadows, a painter is painting something about the light: the bounce light, the ambient light; if it can be seen, it has light touching it somehow.
The light has a color to it that will be felt by the viewer as warm or cool, and will influence the local color of the object. It's smart to try to understand this, as it does influence color choices. A blue light on a red ball will make the local red color look different (purple) from a yellow light on a red ball (orange). This is because blue and red make purple, and yellow and red make orange! The funny thing is, if you paint it right, it will read "red," even if it was actually painted with purple or orange pigments.
And the shadow that will be cast is different according to the color of the light as well. "Warm" light casts a cool shadow; "cool" light casts a warm shadow. The first thing a painter has to do is determine the color of the light.
Each of these four studies, done when I was painting with Gerhartz, was painted in a different light. I was glad to be able to really closely scrutinize the temperature and relationships for as long as I wanted. Well, as long as I wanted in three hours.
(I don't know how these will be presented in the email version of this post, so if you want to see it in its natural and deliberate format, please click www.kimcarlton.blogspot.com )
You've already seen part of one of these in the last post. Here are all four:
There is cool natural light (the girl with the flower); cool natural with warm artificial light (the girl in the kimono); cool artificial light (the auburn-haired girl); and warm artificial light (the man). The most challenging one was the cool natural with warm artificial light. Most of the face was in shadow and I had to concentrate to discern the temperature there. In spite of the warm artificial light, the shadow was warm, maybe due to the overall cool light pouring in through the north-facing windows. The studio is painted a warm color so that would also affect the feel of the bounce light.
No matter where we are or what we're looking at, it's all about the light. The purpose of most representational painters is to share a light impression, regardless of what the objects in the painting happen to be. I feel like it is true in life as well: it's not about the objects; it's all about the light. The way you see the world is related to the kind of light you put on it.