In the fall 2006 issue of Drawing, we explored the art of drawing realistic heads. Here, we present an excerpt from the article about drawing with light and shadows.
by Dan Gheno
|Study of a Boy With His Hand to His Mouth
by Giovanni Battista Tiepolo, pen and brown ink over black chalk,
9 5/8 x 7¾.
Squint your eyes when you look at the model, and assess the big value masses as Tiepolo did in this strongly graphic drawing. All the details should merge into the bigger shapes. None of the details in shadow should jump out and appear as light as anything in the light shape, and none of the lights should look as dark as anything in the shadow.
I could write an 8,000-word article on the subject of drawing light and drawing shadow—indeed, Leonardo enthusiastically filled more than six notebooks dedicated to the subject (plus many extensive passages in other notebooks). Briefly put, once you find the outside contours of your head and features, you need to see the "third line" within the limits of your forms—where the light terminates and the shadow begins. Called "the terminator" by astronomers, this line helps establish the inner form where the big planes of the head meet and turn crisply. Therefore, the light on the eye and the cheek that is closer to the light source is almost always brighter than the ones that are farther away. As an example, let's say you're drawing someone with a weak chin, illuminated from above by a bright lamp. You may correctly place all of the terminator lines, perhaps finding a strong shadow shape running down the length of the face from forehead to chin, as in the drawing above by Tiepolo. But if you make the broad lights on the lower part of the face the same bright value as the forehead, the chin will not recede and you won't achieve a likeness or a sense of full volume no matter what else you do.
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