There's an old rule that animators keep in mind: "Put it where you can see it."
It's true for illustrators, too. When you're designing a picture, the parts of the pose that are important to the story should be in clear view, while the less important parts can be concealed.
For this illustration in Dinotopia: The World Beneath, I wanted to show Arthur Denison helping a young Giganotosaurus free his foot, which was trapped between some fallen logs. While I was planning the picture, I thought about what things I needed to show to explain what was going on: Arthur's face and hand, the dinosaur's face and the tip of his tail, his ankle, and the logs.
I didn't need to show the dinosaur's hands, Arthur's feet, or the details of plants on the ground, so those parts could be hidden or blurred. The greenish brown background tone helps to disguise unimportant edges at the bottom of the picture.
Because Arthur's face was especially important, I contrived a lot of lines to radiate out from it, a compositional technique called "spokewheeling."
More about the rule in the book: The Animator's Survival Kit
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