The inherent lightness or darkness of a form - its local-tone - is a given quality of all forms. It is affected by, but separate from, the light and dark areas that result from light falling on forms.
Nathan GoldsteinValue gives the artist the means of showing subtle changes in a form's surface-state, and it helps clarify the relative distance between forms.
Nathan GoldsteinValue, whether the result of massed lines, broad strokes, or washes, is the necessary and only tool for modelling form with light.
Nathan Goldstein