Final answer:
The method that artists use to apply value to 2-D artwork to create the illusion of 3-D is known as chiaroscuro, which is characterized by the contrast of light and dark. Artists also use perspective, including linear and atmospheric perspective, to convey depth and volume on a two-dimensional surface.
Step-by-step explanation:
Various methods are used by artists to apply value to 2-D artwork in order to create the illusion of 3-D art. One such method is chiaroscuro, which involves the use of strong contrasts between light and dark to give a sense of depth and volume. For example, artists like Raphael employ chiaroscuro by using variations in value and strategic shading to make subjects, like the woman in La Donna Velata, appear three-dimensional on a canvass. Similarly, the technique of perspective plays a crucial role, where linear perspective involves the use of a vanishing point to create the illusion that objects shrink in size and space. Atmospheric perspective, on the other hand, uses color and clarity to indicate distance, with distant objects appearing paler and less defined, as seen in works like Albert Bierstadt's The Rocky Mountains, Lander's Peak.