Bright oranges and yellows create cheerful moods, reds are exciting, blues and greens are calming and serene, violet is mysterious. Intensity refers to the strength the hue. Browns are low intensity reds. Changes in intensity can be used to reveal form as in the illustration to the left. Foreground objects tend to have higher intensity colors than background objects.
Value is variation in lightness and darkness.
Changes in value are the primary means of shading objects to convey form. Warm and Cool Colors Colors such as red, yellow, and orange, that are associated with sunlight, excitement, and action, are called warm colors. Blue and blue-greens are associated with ice and water. These are called cool colors. Warm and cool are relative terms since a red may appear cool next to a bright orange.