The degree of difference can range from subtle to intense, depending upon how soft or sharp the contrast appears. Tonal contrast is characterized by differences in light and dark values within a limited range of pigment. This type of contrast is often displayed in pencil, charcoal, or ink drawings. Other tonal works include monochromatic illustrations that contain a very limited range of similar colors. Here again, the focus is on value differences and not the range of colors used.
Color contrast is defined by the comparison of, and differences between, certain colors.
Complementary colors are those that aesthetically contrast when used in close proximity. This is a key color theory concept that is universally practiced by most knowledgeable painters. True complementary colors are those that are located opposite each other on the color wheel. For example, cyan blue is the complement of red, magenta for green, and yellow for dark blue. Complementary colors become most effective when they produce maximum color contrast.