The painting technique Leonardo mastered, using subtle transitions between colors, is sfumato. The term comes from the Italian word fumo, meaning “smoke,” and describes edges that appear softened rather than outlined sharply.
Sfumato creates gradual shifts between light and dark and between neighboring colors. Leonardo used it to make faces, atmospheric backgrounds, and forms appear more natural, particularly in the Mona Lisa and Virgin of the Rocks. The effect reflects his interest in optics, shadows, and how human vision perceives objects at different distances.
Sfumato is often confused with chiaroscuro. Chiaroscuro emphasizes strong contrasts between light and shadow, while sfumato focuses on delicate blending and disappearing contours. Other Renaissance artists, including Raphael, Correggio, and Giorgione, also used the technique, but Leonardo is its most celebrated practitioner.