Much ink has been spilled about the color wheel and the multitude of strategies for creating harmonious yet dynamic color schemes. I am no expert in color theory, but I have learned my fair share from experience designing magazines and creating illustrations for children's books.
The importance of maintaining a coherent color scheme throughout the illustrated children's book cannot be understated. It is a fundamental technique for establishing unity throughout the story and controlling the mood of each illustration without alienating certain parts of the story.
Good stories have emotional variation, so it's necessary for the color scheme to be flexible enough to accommodate a range of moods and feelings. A perfect example lies in the depictions of the school in my fourth book. There are two images of the school's facade back to back in the book, one cheery and optimistic, the next sullen and dejected:
Both of these paintings are composed of the same basic colors, which allows for totally oppositional moods to still feel part of the same story. These are subtle things that no reader is thinking about, but being careful about these quiet details as an artist takes your project to the next level. This is not something I was conscious of on my first books—I was way too concerned with representing the story "correctly" and figuring out how to use my techniques to make sensical illustrations.
Before you can apply your color scheme to creating multiple coherent illustrations, you—perhaps obviously—must decide on a color scheme. This can be easy or difficult, depending on how many colors of paint you have to choose from. I have a palette with 14 colors of watercolor paint on it, which is pretty generous. I can defend my choice to have lots of colors on my palette later. The point is that I have to do a lot more work paring down my palette to generate a good color scheme than someone who only keeps 6 colors on their palette.
On the right is the color scheme I chose for the book I'm using as an example for this post (12 colors). Above are the 14 colors that are natively on my palette.
You may ask, "What's so hard about trimming a 14-color palette down to a 12-color scheme?" It's not about the number of colors. It's about the balance between the colors you do choose and how you can modulate those colors to fit the needs of your illustrations.
The middle row of my color scheme in the image at right above is the core. Because the book project comprised 15 some paintings, I needed every primary and secondary color. This was also because the story was about a school and I wanted a pretty traditional, elementary feel. But I also included six mixed/muted colors on top and bottom of those core six. I'm calling these "fringe colors." These are important because they restrain willy-nilly mixing, which can undermine your color scheme. When I needed more neutral colors in a background, I tried my best to stick to these gray-violets and gray-greens.
"What about those oranges? Those are hardly neutral!"
This color scheme is the backbone for the color profile of the book. So whatever colors I was planning on including in the illustrations, I needed to represent in this color scheme. That way, I could decide whether my choices were balanced and harmonious before I started. I knew I wanted more warm colors than cool, and I knew the oranges were going to be important for the youthful attitude they impart (again because of the subject matter). So I needed to dignify these colors in the color scheme.
At right are samples of three paintings from the book. Notice how they almost feel as if they could be pushed together and form a single painting, color-wise. There's consistency in the core colors, yet they're flexible—the middle painting is a flashback to the school in the 70s, yet I was able to use the same color scheme to illustrate this totally different era.
You may notice a glaring exception in some of the images I've included in this post: the blacks and browns. These are really functional colors for shadows and adding deep values, but they're not part of my "official" color scheme. Black and brown tend to go with almost any combination of colors because they're made by mixing almost all the colors. So all six of my core colors are represented in that brown (theoretically), and that's why it works with my color scheme, and with almost any color scheme you can come up with. Black is the same way.
These are the fundamentals of what I've learned about using color strategically in multi-image illustration projects. The coherency of colors throughout a book lends a sense of legitimacy and sophistication to your work and helps you to control the mood of your illustrations.
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