When pencil shading, the first thing most people do is to move the pencil back and forth in a regular pattern, with the 'turn' at the end of each movement roughly parallel, as in the first example. The trouble is, when you use this technique to shade a large area, that even edge gives you a dark line through your area of tone. Sometimes it is only subtle, but often it looks very obvious and spoils the illusion that you are trying to create with your pencil shading. Let's look at some ways to fix this.
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