Renaissance_ A Short History, The - Johnson, Paul [50]
Roman methods of wall painting never wholly passed out of use in the West, though they lost their complexity and sophistication. From a crude base, then, techniques were gradually improved, rather than revolutionized. In the age of Giotto, the procedure was as follows. The surface was smoothed. Then a rough arriccio was applied, one part lime, two parts water. The painter then drew the outlines in charcoal and went over them with a brush to produce the sinopia. The entire work was then divided into sections, each one of which could be finished in a day—these were known as giornate. Then, at the beginning of each day, the allotted portion was covered by the intonaco, the outlines were drawn in again and the painting proceeded. Some bits could then be redone in secco, but with all its disadvantages. The technique is described in detail in Cennino Cennini’s treatise, Il Libro dell’arte, published about 1390. It has one huge and obvious disadvantage and one less-obvious but important advantage: Fresco painting meant final decisions had to be made at an early stage in the work. Once the sinopia was complete and measured up, no major changes in composition were possible, and even minor changes raised problems. Spontaneity was ruled out, and as the painter saw his work emerge, he must have been agonized by the faults and misjudgments that emerged too, and he could not correct them, as a rule, without starting all over again. Hence, despite the growing freedom of treatment that artists enjoyed thanks to foreshortening and perspective techniques, a certain formality and woodenness persisted even in the best work of the early Renaissance.
On the other hand, in Florence in particular, where fresco was always ruthlessly preferred to other methods, artists were forced to think out their projects carefully in advance, and to prepare for them with detailed drawings, of the whole and its parts. This was the great advantage of the system. It made the Florentines concentrate on what they called disegno, which embraced both design and draftsmanship. Florentine artists, or those trained in Florence, thus formed the habit of producing countless drawings, thousands of which survive and some of which—Raphael’s, for instance—have become among the greatest treasures of Western art. The drawings were increasingly from life, enabling Florentine artists to observe the human form with fiendish concentration and reproduce it with wonderful fidelity. The glories of the High Renaissance, and its celebration—one might almost say sanctification—of the human body, would have been impossible without this meticulous tradition of draftsmanship.
All the same, wall painting in fresco imposed odious limitations on excitable and volatile painters. Mixing pigments with egg yolk has many drawbacks. Some pigments have to be excluded altogether. The paint has to be applied thinly, using a delicate hair brush with a point. It cannot be applied thickly, with impasto, and if the artist wants this kind of effect he has to put on repeated layers. He cannot apply the paint smoothly, so that his brushwork becomes invisible, but has to produce a hatched or stippled effect, extraordinarily monotonous on close inspection. He cannot blend or fuse or mix his colors and tones on the surface, which rules out any of those delightful accidental effects that rejoice the heart of every good artist, and which, more important, means that he