How I Shade Across a Drawing

Shading a face is challenging . . . the hair, the chin, the eyes.  Trickier still can be shading a face across the entire page.  Let me explain.

To shade a face (or any subject for that matter) across an entire page, I just answer one question.  Where does the strongest light come from?  In the following example, the strongest light comes from the front-top-left.  How does asking this question help me?

Knowing that the strongest light comes from the front-top-left tells me where the lightest part of the entire drawing is-the top left!  Any point closest to the strongest light is always brightest, even if I can't discern that with my naked eye.  And since light travels in a straight line here on earth, the side opposite that brightest spot (where the light hits my subject last) will be the darkest-the bottom right!  You can see what I mean in this example, where I've shaded the paper without the face.

Now I put the two examples together.  The face goes from having been shaded, to having been shaded across the entire drawing.

Shading across an entire drawing can get even trickier.  For instance, what if there were more than one light source?  What if there were more than one subject?  And what if these subjects were different distances from the viewer?  I'll be writing about these later!