Value and contrast are often dependent upon the texture of the the object being rendered. In the diagram above, you can see that the sphere on the left, although adhering to the characteristics of chiaroscuro, does not seem to have a graduated change in value. This is caused because the texture of the sphere is somewhat like that of a wound ball of string and there are additional values breaking across the surface. These lines help to create value and by overlapping the lines one can create lighter and darker value gradations (hatching and cross-hatching).

The cube in the center has a pattern which appears to darken on the top plane. What is actually happening is that the background behind the pattern has lightened, creating the illusion of darker spots.

The cylinder at the far right has a slick reflective surface. In such a surface there is a broad value range, usually from bright white to black. The transitions between these extreme values is usually more sudden than on a matte or heavily textured surface. You will find that reflective surfaces placed in compositions with heavily textured objects will create interesting contrasts that compliment each other.

Hint: When dealing with texture, remember that heavily textured items will have slow gradual changes in value unless the plane ends abruptly. In contrast reflective surfaces will have sudden changes in value, from one extreme to another, with only slight changes in the direction of the planes.