Value in art is how light or dark a tone is, whatever its color. A painting built on value still holds together when the color is taken away, because value is what gives a face its roundness and a figure its distance from the wall.
The picture where it is easiest to see is Caravaggio's The Calling of Saint Matthew, painted around 1599 to 1600 for the Contarelli Chapel in San Luigi dei Francesi in Rome, where one slanting beam of light cuts through a nearly black room.
Painters check value with a plain test. They squint at the canvas, or photograph it in black and white, and the colors drain away until only masses of light and dark are left. If the picture still reads, its values are right.
Cool Stories About Art is a newsletter to learn art the fun way.
Join 200,000+ readers and get:
10 new art stories / month
The entire archive of content (140+ articles)
Comment, ask questions, and chat with other readers
In the Calling, value does the staging. A beam of light slants down from the upper right, from a source the painting never shows, and lands on the faces of men sitting around a table where a tax collector has been counting money.
Everything outside the beam sinks into shadow. Christ, half hidden behind Saint Peter, stretches out one hand, and the light has already told the viewer where to look before any gesture is read.
What the light does not say is whom Christ is calling. Tradition names the bearded man who points at his own chest as Saint Matthew, as if he were asking whether he is the one.
Another reading says that man is pointing at the young one at the end of the table, whose head is bowed over the coins. Value led every viewer to the right faces and then left them to argue over which one belongs to the saint.
Which man is Saint Matthew?
Nobody has settled it. On the usual reading, Matthew is the man who points vigorously at himself, with Christ reaching toward him from behind Saint Peter, where only his head and right arm show…
What You'll Discover
Who gave value its name.
What Whistler called his mother.
Why one painting has no color.
What hides under the black.