The Four Accidental Colours of Tree Foliage
Shadow, light, lustre and transparency, and how they merge at a distance
In two short red-chalk notes Leonardo defines the "accidental" colors of tree foliage as four: shadow, light, lustre and transparency. He then adds a rule for their demonstration: at a long distance the accidental parts of the leaves blend into a single mixed appearance, which takes on most of whichever accident occupies the greater area. The page carries only these notes, with no figure.
On this page
The four accidental colours of foliage
Leonardo names the accidental colors of the foliage of trees as four: shadow, light, lustre and transparency. These are the appearances the same leaves take on under light rather than their own local color, the raw material of any painter representing a tree.
Foliage colours blend at a long distance
Of the accidental parts of the leaves seen at a long distance a mixture is formed, which partakes more of whichever accident is of the greater size. Thus a distant crown of leaves reads as one merged tone dominated by its largest component, whether that be shadow, light, lustre or transparency.