Perhaps the most important element to painting is the use of values.
Put very simply value is the amount of light and dark in a given color. Artists use value to express three dimensions and depth in their work.
Color and value
All color has value. In this example the painting has been altered to show how the painting still works even without color to help express depth. We will talk a lot about the use of values. Artists often play with color in a painting while keeping the value relationships. For example, the painting could easily be painted in any color so long as the values continue to unify the painting.
As stated above, colors relationship to value is essential to expressing depth. In the example, the painting is now shifted to warm hues. Because the values have not changed the colors can be played with. They are now painted with a palette of warm colors.