The technique of painting, as I have already said, is not to be confused with the style of painting or personal touch of the artist. Technique is the artist's trade, which he must master in order to be able to express himself. Technique, however, is closely connected with the artistic idea: a painter who is master of many techniques will not only interpret an experience or visual impression into a formal composition, but will also immediately translate his vision into a definite technique. Some people go about it the other way: they have devoted themselves to a single technique and only let themselves receive visual experiences which correspond to it.
Rembrandt, for example, was never, from all we know of him, inspired to a picture by a tender balmy spring landscape which would require the soft transparent coloring of watercolors. Rembrandt had to use oils in order to achieve his mysterious deep darkness from which he could then draw out the light only with thick layers of paint. Perhaps one could say more correctly that his motif dictated this particular technique, which could o'nly be oil painting; and from this technique, the famous chiaroscuro, he never deviated.
Titian also often painted on a similar principle, i.e., bringing the light out of the darkness, but he used a less heavy painting for the light and gave an essential role to a light underpainting, letting it shine through the thinnest glazes, sometimes using 30 or 40, one over the other, and at the end putting in a few opaque lights. Titian's pictures often stayed in the studio for months, as each layer had to dry out before he went on to the next; so he had several pictures under way at the same time. Monet or Cezanne would not have got very far with such a procedure. They painted mostly outside from nature at an intense tempo. The picture was begun in a few hours and often finished without a break. The Impressionists used the so-called alia prima oil technique which can be executed only with the most consistently behaved tube oil colors.
Value judgments are irrelevant to a painting method insofar as it is a means of expression, but a picture can be judged from the technical point of view with absolute standards. The best technique is that which maintains the picture permanently in the condition in which it was left by the artist. Permanent is a strong word, for ultimately all material is perishable. Experience shows, however, that paintings which have not altered after a few years or decades can last for centuries without traces of decay.
You already know what the different factors are which contribute to this problem: the three components, pigment, ground, and binder. The most problematical is the binder, the least complicated, the color. The ground or surface stands in reliability between the two. But even the best technique is uninteresting if its materials are wrongly or imperfectly used. And the picture is uninteresting if it speaks to no one and provides no experience. However, whoever has taken the trouble to learn painting properly will surely have something to say with it.
The whole wide range of techniques stands between the two poles of watercolor and oil painting. All the rest are intermediate modes of expression, to be recognized externally from the depth of color obtainable. It can be theoretically imagined thus: watercolor works from a white ground into the color and dark and soon reaches its limit there; oil painting grows from the depth of darkness into the light, which can extend through colors to pure white-white put on and not achieved by leaving out, as in watercolor.
This, at any rate, is the broad principle of technique, which can, of course, be varied, particularly in oil, where it is possible to work with the thinnest transparent paints of which watercolor consists entirely. With these transparent paints it is possible to achieve a glow of color comparable to fhe stained glass of a cathedral when the light is shining through it.
The many techniques are best understood by experimenting with the tendencies and styles of the two opposed methods, both in seeing and execution.
The similarities and differences in painting can perhaps be best explained by a comparison with music, for both arts have many ideas in common, even many common terms - for instance, "tone," "color harmony," "tone color." A painting can be compared to the many-colored sound of a full orchestra,
a solo song to a drawing. As in musical.
technique there are in painting many Italian terms which cannot reasonably be translated: al fresco, fresco-secco, alia prima, sfumato are words familiar to every painter and art historian. A comparison with instrumental music will make the qualities of watercolor and oil technique quite clear: the watercolor begins with a soft and gentle note and ends with a full deep concord. Everywhere at the same time the greatest depth of which it is capable should be enveloped in the fluidity of the lighter colors.
The oil picture begins with a mild deep sound of solo wind, grows in the many colors of the full orchestra, over which stand out the trumpets and horns with the brightest tones; violins and flutes draw light contours, and the high lights resemble the echoing cymbal.
Even if an oil painting is performed in the hurried pizzicato of Kokoschka the mark would be legato and the time andante. Watercolor can only be prestissimo; the technique allows of no exception.
Technically speaking, watercolor is the simplest way of painting. (This you know already from what has been said about water paints and paper.) When it comes to ability, however, and sureness, it is one of the most demanding of all techniques on the painter's ability.
Oil painting requires a thorough knowledge of the materials, and the way the picture is built up technically needs to be well thought out if it is to last. The old masters knew their job so thoroughly because they produced, or at least prepared, everything themselves: the grounds, pigments, and, most important of all, the binders. The Impressionists (and not they alone!) relied on the products of industry which were just coming on to the market and were by no means perfected. They worried very little about the technique of mixing and putting on paints, and the result is what one would expect: very many pictures of the second half of the last century are deteriorating irretrievably.
A consistent oil color has never been found which will stay unchanged in both upper and under layers. Added to this the different pigments influence the setting time of oil binders. For this reason oil colors cannot be worked with so unconcernedly as watercolors. On the other hand, with oil colors you can, if you go the right way about it,
work at the same picture either at one sitting or after weeks or months, glazing and repainting solidly.
If you are equally conversant with the principle of watercolor painting and with the various ways of painting in oils you can proceed with all the other techniques. A painting with reversible glue as binder can be done as quickly as a watercolor, but it also allows as leisurely work as oil colors. This depends entirely on what you wish the final effect to be. Fresco on damp plaster requires the same speed, and as far as possible single-coat painting, like watercolor, while with frescosecco you have plenty of time and can overpaint as you wish.
Painting with genuine tempera and the mixed techniques of mineral painting allows both the thin transparent texture of watercolor and the opaque, even-modeled effects of oil color. Pastel is the only exception; it is made up of fine or broad lines, but this you already know from the section on drawing.
Next: Watercolor painting