## True Modeling Of Rounded Form

The simplest way to explain the fundamental principle of rendering light and shadow is to think of a ball with light focused upon it just as the sun lights the earth. The area on the ball closest to the light is the high light (A), comparable to noon. If we move on the surface of die sphere away from the high light in any direction, we find that the light begins imperceptibly to fade into the halftone arca (fí), which may be compared to twilight, and then to last light (B+), and on to night (C). If there is nothing to reflect the light, there is true darkness; however, if the moon, a reflector of the sun's light, comes up, it will reflect light into the shadow (D). When light is intercepted by a body, its silhouette falls upon the adjacent light plane. This, the darkest of the shadows, is callcd "cast shadow." It is still possible, however, for a cast shadow to pick up some reflected light.

The artist should be able to look at any given place on his subject and determine to which area it belongs — the light, the halftone, the shadow, or the reflected light. Correct values must be given in order to obtain unity and organization of these four fundamental areas. Otherwise a drawing will not hold together. Treatment of light gives a drawing cohesion no less than structural form.

There are many things you can learn from photographs if you use them intelligently. Remember, however, that the range of light to dark is much greater in the eye than in pigment. You cannot possibly put down the full range; you have to simplify.

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