A Treatise on Painting/Chapter 187
Chap. CLXXXVII.—What Light the Painter must make use of to give most Relief to his Figures.
The figures which receive a particular light shew more relief than those which receive an universal one; because the particular light occasions some reflexes, which proceed from the light of one object upon the shadows of another, and helps to detach it from the dark ground. But a figure placed in front of a dark and large space, and receiving a particular light, can receive no reflexion from any other objects, and nothing is seen of the figure but what the light strikes on, the rest being blended and lost in the darkness of the back ground. This is to be applied only to the imitation of night subjects with very little light.