The Air Between the Eye and the Object
Aerial perspective, and the three perspectives that make up painting
This all-text page turns from mechanics to painting. Leonardo argues that at a given distance an object appears more or less distinct according to how rare or dense the interposed air is, so the painter should let the definition of a body's outlines fall off in the same proportion as its distance from the eye. Under 'On the parts of painting,' he states that the first part is to make bodies appear in relief and their backgrounds recede into the wall by means of the three perspectives, that is, the diminution of the figures, of their sizes, and of their colors. The second part, he adds, is giving figures appropriate actions and varied statures so the men do not look like brothers.
On this page
Definition fades with the interposed air
An object shows itself more or less distinct at the same distance according as the interposed air is more or less rare; knowing that a greater or lesser quantity of air makes a body's boundaries more or less confused, the painter should lose the definition of bodies in the same proportion as their distances from the beholder's eye.
The three perspectives of the first part of painting
The first part of painting is that bodies appear in relief and their fields recede into the wall by means of the three perspectives: the diminution of the figures of bodies, of their magnitudes, and of their colors. The first arises from the eye, the other two from the air between the eye and the objects seen.
Rarity of air and the confusion of edges
The quantity of air interposed between eye and object governs how confused the boundaries of bodies become to the eye, two of the three perspectives deriving their effect from that intervening air rather than from the eye itself.