The setting sun over mist, clouds and city: precepts on light
Colour perspective, reddening light, and the central-line rule of light and shade
The page opens by distinguishing linear perspective, which does not diminish the visual angle, from the perspective of colours, which pushes an object to a greater apparent distance while preserving its size, so distant things look larger and blurred. A series of numbered precepts then treats the setting sun: falling mists thicken the air, shaded things stay dark and confused while lit surfaces redden and yellow, and city buildings stand out sharply because of their dark shadows. Further notes describe clouds lit from below near the sun, the two shadows cast by sun and sky, and the rule that the central line of primitive and derivative light coincides with that of the shadows.
On this page
Colour perspective enlarges and blurs distant objects
Leonardo explains that an object of uncertain, confused outlines can appear larger than it is. Linear perspective does not diminish the angle carrying the object's image to the eye, whereas the perspective of colours drives the object off to a greater distance than it really is: one removes it from the eye while the other preserves its magnitude.
The setting sun reddens what it lights and darkens the rest
When the sun is in the west, the falling mists thicken the air; things not seen by the sun remain dark and confused, while those it illuminates redden and yellow according to the sun's position at the horizon. Everything appears of a single colour unless it is directly seen by the sun.
A sunset townscape: lit buildings against dark shadows
Houses lit by the low sun are strongly evident, especially the buildings of cities and villages, because their shadows are dark; their clear appearance seems to rise from confused and uncertain foundations. This gives painters a rule for rendering a landscape of towns at dusk.
Two shadows, and the central-line rule of light and shade
A precept notes that clouds between viewer and setting sun are lit below while nearer ones stay a reddish dark. A body lit by the sun is also lit by the air, creating two shadows, the darker being that whose central line runs straight to the sun; and the central line of the primitive and derivative light always aligns with that of the shadows.