Sfumato: Leonardo's Smoky Secret

Sfumato is a technique that uses fine shading to create soft, imperceptible transitions between colors and tones. The word comes from the Italian sfumare, “to tone down” or “to evaporate like smoke.”¹

The National Gallery in London describes it as the “smoky” quality that blurs contours, so that figures emerge from a dark background through gradual changes of tone, without any harsh outlines.²

In his unfinished treatise on painting, Leonardo advised painting “without lines,” and you can see that atmosphere in his own works.²

He and his followers built subtle gradations from light to dark with no lines or borders, for very lifelike faces and for atmosphere.¹ Here, the angel's cheek simply turns into shadow.

The two are cousins. Chiaroscuro is about the contrast between light and dark; sfumato is about the softness of the passage between them. Britannica links them directly.¹

The most famous example is a smile. In the Mona Lisa, soft, smoky transitions with no hard outlines make the face seem to move and the smile flicker.³ (Her eyes are another story: see the Mona Lisa effect.)