Chap. CLXXXIV.—Of Drawing by Candle-light.
To this artificial light apply a paper blind, and you will see the shadows undetermined and soft.
Chap. CLXXXV.—Of those Painters who draw at Home from one Light, and afterwards adapt their Studies to another Situation in the Country, and a different Light.
It is a great error in some painters who draw a figure from Nature at home, by any particular light, and afterwards make use of that drawing in a picture representing an open country, which receives the general light of the sky, where the surrounding air gives light on all sides. This painter would put dark shadows, where Nature would either produce none, or, if any, so very faint as to be almost imperceptible; and he would throw reflected lights where it is impossible there should be any.
Chap. CLXXXVI.—How high the Light should be in drawing from Nature.
To paint well from Nature, your window should be to the North, that the lights may not vary. If it be to the South, you must have paper blinds, that the sun, in going round, may not alter the shadows. The situation of the light should be such as to produce upon the ground a shadow from your model as long as that is high.
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.