1. - A soft lighting and without distorting it it is the one that is obtained by a focus which light projects it bounced from the wall.
2. - If the sculpture needs a wide lighting it is achieved by two foci: one directing the light to the roof so that it receives it bounced and other straight towards the work.
3. - If one does not try to accentuate the volumes of the work, the appropriate lighting is the one that comes to him widely from above.
If the light is projected loudly and from only one angle it highlights the volumes of the same one, accentuating and hardening his expressiveness.
Leonardo points out that one of the differences between painting and sculpture consists of the fact that the first one possesses proper light, while the light of the sculpture is exterior.
As he explains himself in The keys of the sculpture / the light "it is necessary to warn that the sculpture possesses two lights: the proper one, which the same sculptor tries after the planes of the volume work, with his protrusions and inlets, and that of the luminous focus that lights it."
We can perceive, then, jointly a luminous focus, the clair-obscure one of the sculpture and the shades that express the volumes beyond the figure.