Charles W. Hawthorne wrote, "If you will only put a spot of color in the right relation to other spots, you will see how little drawing it takes to make form. Let color make form, do not make form and color it." Hawthorne was not suggesting that we care little about drawing skills, he was suggesting that we learn to see color in relationships, and that by doing so, we will be drawing without ever having had the first thought about the actual "noun" we are trying to describe with paint.
Color terms seem to overwhelm us. You really only have three questions to answer when determining color.
Is it cool or warm?
Is it neutral and intense?
Is it light or dark?
The answers, however, are always relative to every other color used while fitting together the painting-puzzle. You cannot simply say that red is warm any more than you can describe the intensity of the spring green grass, or the lightness of the new mauve color you have just chosen to paint the walls of your dining room, without also giving a frame of reference in which make comparisons. The local color of a red of a tomato may be relatively warmer than, say, the local color red of a cherry. The only reason spring green grass appears so intense, is because the greens in winter are not. If the dining room wall is described as light mauve, it is probably painted somewhere darker than pure white, but lighter than your cherry dining room table. For this reason, I have not broken down color and value into two separate subjects here, but instead always think of color and value as one.
Let me stop here to make sure you understand a term I just used: local color. Local color is that hue name we use to describe at an object when the least amount of external effects have changed it. So, for instance, the local color of a red cherry is the hue red. Let's use something a bit larger to help you understand. The next time you are in a room that is painted a color (as opposed to white, tan, or other neutral) try this. We'll use an imaginary "red" room for our example here. Identify the wall in the room that appears closest to the red you learned as red in your crayon box. At some angle in the room, you might see something darker, that is, in shadow. At another angle you might have bright light from a nearby window and you would normally identify this as something lighter. But don't stop there. Let's try to identify the color, not just the value.
Using your "hand-y" view finder, isolate a spot on the wall you have identified as red. (Below I describe how to make your handy view finder.) Now, while looking through the view finder, move your eyes from wall to wall. Notice how the color you see through the hole in your hand changes? What you were taught is that this is a red room. If you can let that go, and forget that it is red, what you actually see could be called any of the other colors in the spectrum. This takes some practice, because for however many years old you are, you have been taught that red is red. But if you keep trying, it's like one of those magic pictures, suddenly you will see it and it is a HUGE step to painting growth when it does.
Okay, so that was a lot of explanation, but let's get back to the original post here. As a cherry painter, you might realize at this point, that every time there is a plane change, a change of direction in the surface of the cherry closer to or further away from the light source, there is a color change--not just a change in value. "I'm a landscape painter," you say, "I would never paint a cherry anyway. What good is this information to me?" Ah, because if you learn to recognize color as it sits in relation to other colors, whether on an objects or in a scene, you will never have to remember the "rules" of atmospheric painting. It will all become natural, just as walking or talking or reading. Otherwise, you will be doomed to a life of rules that will, doubtless, produce some pretty nice pictures, but all start to look a like. You might never fully learn how to describe overcast days or foggy mornings as they compare and contrast to bright sunny days with long-drawn shadows. For me, personally, that is much less satisfying than being a part of the interpretation and development of the painting. Try the handy view finder to observe how the colors on the form of a tree change as the form turns. Now compare those colors with the colors of the distant trees. As you identify the color by it's hue name, also identify if it is lighter or dark than the other colors you just identified. Warmer or cooler?
Each of us sees a bit differently. That's where YOUR interpretation comes in to this practice. Also, the way you edit or use of the information that you gather will make the painting YOURS, not mine. That's another subject for another day.
I must say that the rules that have been presented to us are pretty good ones. Because of the effects of atmosphere (that is layer upon layer of smog, fog, humidity, haze, etc.) on light rays, there are some predictable ways color will bend and be changed. There are tons of websites describing these scientific effects. If you're a lover of all things science, and I have to admit there is that side of me too, try this one, http://www.handprint.com/LS/CVS/color.html. You can get lost here for days!
But what I love to do, is find a scene that defies the rules and try to interpret it accurately. That's where the interest is for me as an artist. Compare the images I have included here. Even without titles like "mid-day delight," "afternoon sun," or "morning fog," you can imagine the setting and time of day these were painted. This is why you will hear me say time and time again, that I do not want to paint "nouns." Don't teach me to paint a palm tree. I want to learn to paint adjectives and adverbs . . . descriptions.
Seriously, nothing is new that I am sharing here. My mentor charged me to share what has been shared with me, run through my tiny "Lori filter" brain, and I hope you feel free to pass it on.
Instructions for making your handy view finder: Make a closed fist. With your thumb and forefinger still in "fist" position, raise (but relax) your other three fingers. It's a little like a very tightly close "ok" hand sign. Hold your hand out at arm's length NOT UP TO YOUR EYE. Glance through the tiny hole made by your thumb and forefinger. GLANCE . . . do not stare. The first color that comes to your mind, is the color you should identify. The best part about this viewfinder is that it is free and always with you... how handy!