One of the challenges for a picture book illustrator is to find ways to include the text in the illustrations. In older books, the practice was to run the words along the bottom of the page and leave the illustrations free of any text. Nowadays, that look is considered old-fashioned, and it’s up to the illustrator to provide blank areas within the pictures as a background for text, to make the whole thing more organic.
You’ll notice also that the text is always black, never a color. There’s a good reason for that: if you ever needed to publish the book in a different language, black-only text is simpler and less expensive to change. To understand why that is, you’ll need to understand 4-color printing.
Remember primary colors?—blue, red, yellow. They can be mixed to create any color in the spectrum, the rainbow. When you look at an illustration in a picture book, you’re looking at a painting that’s been digitally reduced to tiny dots—blue, red and yellow dots. These dots are printed on white paper, so if you let more paper show in between the dots, the color will look lighter. If you want to darken a color, you add tiny black dots. So there are the 4 colors of the printing process: blue, red, yellow (the primaries), and black.
So if you keep an area of the picture light, and print the words over it in black, you’ll only need to change the black plate if you need to translate the text. If you printed the words in color, you’d have to change all 4 plates—more expensive. Likewise, if you had white type drop out of a color background, you’d also need to change all 4 plates if you were to change the words.
I faced a dilemma when drawing the sketches for Where’s My Mummy? In order to make the pictures look spooky, there had to be a lot of dark areas. But where to put the text? Leaving big pale patches in a dark tree trunk wasn’t acceptable. Caroline Walker, the art director, came up with a brilliant idea: since my dark areas were all blueish gray, have blue type drop out of the black plate. She explains it here: