A friend asked me to "Take on art teachers that won't allow/discourages students to use black for their artworks."
First off it’s impossible for me to know exactly what your teacher is telling you, so it’s not fair for me to challenge them in absentia. However, I do have some things to say about this topic in general. Also let me be sure to include my usual disclaimer, if it needs to be said: Y'all can obviously paint however the heck you want.
CHALLENGING DOGMA
The book Art and Fear states (and I keep repeating) that dogma persists not because it is accurate or particularly useful, but because it is simple. Whenever I hear, “this teacher explained such and such so simply I finally understood,” I worry, because it’s just as likely the teaching was easily understandable because it was wrong. I mean, what could be simpler than telling you not to use a certain color at all?
Plenty of painters use black… and plenty of painters AND ART TEACHERS struggle so much with color that they grab onto any rule or system they believe will reduce things looking BAD. That’s how extreme the struggle with color is for a lot of artists. They don’t know how to make it work for them, they only desperately want their colors to not suck. I think we can aim higher.
THE NUGGET OF TRUTH
Most of the admonition against using black probably comes from the insight that “shadows aren’t black.” Unfortunately, for many artists and teachers the understanding stops there (and like most rules… this one isn’t really true). The observation that “shadows” are not black is a tiny but still important baby step in the reverse engineering of vision. It’s analogous to the realization that “eyes are not round.”
But this analogy disproves both assertions, because a) eyeballs are spherical (which is critical to understand if you want to draw them realistically) and b) you can draw eyes as circles if you want. So while it is important to realize that how we reflexively categorize what we see is not really accurate (e.g. shadow = black, eye = circle) , it’s just as bad to simply move to a different level of inaccurately simplistic categorization.
So let me flip this around: If something is not illuminated by anything, it is black (you can’t see it). If you can see something, it is illuminated, and therefore, why do you call it a shadow? So there: the only thing you can legitimately, reliably, and consistently call a shadow IS black.
WHAT IS A SHADOW?
Let me pop this bubble hopefully once and for all: “shadow” is a concept that is handy for referring to an element in a painting, like a cloud, a figure, or anything else. All we can say about this word is it is generally reserved for things not directly lit by the brightest light in the environment. How helpful is that for painting “shadows” or anything else? Well, for one thing it proves that shadows can indeed be black. The only thing they can’t be is white. So don’t use white in your paintings.
DESIGN CONSIDERATIONS
There are also design-based warnings against using black. These, too, have a nugget of truth. You may reflexively choose black for a design element (e.g. line work) when what would work better is some other dark color. Black is a special color. So are white, intense blue-green and intense red-orange. They represent the extremes on the scale of value and temperature, respectively. As such they each occupy a unique place in the color space, and play a special role in a picture, if included. And I haven't even begun to talk about the wonder that we call "yellow."
OTHER COLOR MYTHS
In another insight gone wrong, you are told how all colors influence one another due to simultaneous contrast (via what they are adjacent to). You marvel at how a certain color appears warmer when it’s on a cool background, and cooler when it’s on a warm background. However, invariably, these demonstrations involve a neutral gray square on either a blue-green or red-orange field. What this proves is that neutral colors are influencable by extremes in temperature—but you're not told that the reverse is certainly not true. The great nugget here is about the unique and vital role neutral colors (grays), and particularly middle value neutrals, play in a well-constructed image.
NEXT LEVEL COLOR THEORY
It's an attractive idea: learn a few things about how color operates in general, then apply these across the board. But the next level of understanding is the realization that every color is special and unique in its own way. Different “rules” (I prefer the term “principles”) apply to warm colors, cool colors, neutral colors, saturated colors, dark colors, light colors, and even specific hues such as the one that correlates with what we call “yellow.”
Many artists arrive in this more advanced territory through experimentation, but continue to insist on the validity of the "rules," modified by a few “exceptions,” failing to grasp or admit that THE SO-CALLED “EXCEPTIONS TO THE RULES” ARE THE ACTUAL PRINCIPLES!
Our work only becomes more frustrating and even bewildering, if we continue to deny that the truths that emerge from practice, such as:
1. There is no such thing as dark yellow* 2. It’s impossible to have a saturated blue that is also a light blue 3. It’s impossible to have a saturated red that is also a light red 4. Colors in the warm part of the spectrum appear to shift HUE as their VALUE and SATURATION changes, but this does not happen to colors in the cool part of the spectrum 5. The less saturated a color is the more easily its hue and temperature are influenced 6. The more saturated a color is the more it is able to influence other color hues and temperatures 7. There is nothing darker than black 8. There is nothing whiter than white 9. There is nothing cooler than saturated blue-green 10. There is nothing warmer than saturated red-orange 11. We perceive the lightest color in an environment as white 12. We perceive the darkest color in an environment as black 13. etc.
* Bonus question: A “red object” reflects mostly red light, a “blue object” reflects mostly blue light, so what does a “yellow object” mostly reflect?
CONCLUSION
If you have been having some success with the “rules” but are now eager to "break them” or outgrow them, be willing to FULLY LET THEM GO IF NECESSARY. Have you ever tried to ride a bike with training wheels, once you’ve learned how to balance without them? It’s very awkward! You’re more likely to fall! Just take them off!
If you want to paint convincing light (and thereby “shadows”), you need to understand how light works. Honestly, how light works is not that complicated. In fact it is HALF as complicated as what you are trying to do now, which is to understand how light works AND SEPARATELY understand how shadows work. But you don’t need to understand how shadows work, because shadows don’t exist in any fundamental way. You only need to understand how light works, and using black or refraining from using it is not going to give you that understanding.
This picture is called "Two Friends."