“To draw does not mean simply to reproduce contours; drawing does not consist merely of line: drawing is also expression, the inner form, the plane, and modeling.
Drawing is the probity of art.”
-Jean Auguste Dominique Ingres (1780-1867)
Painting Style & Technique...
From the earliest days of oil painting to the time of this writing (late Twentieth Century, into the early
Twenty-first), a number of oil painting techniques have evolved. A great deal has been learned through the processes of trial and error and from the experiments of various artists through the
centuries. From Jan and Hubert Van Eyck, possibly the first innovators to paint pictures in oils, in the late Fourteenth and early Fifteenth Century, to William Bouguereau, Jean Léon Gérôme,
Alexandre Cabanel, Jehan-Georges Vibert and the other French Academic painters in the late Nineteenth Century, technical knowledge developed more or less continuously, as artists of each generation
added their discoveries to what their predecessors had learned.
The continuity was interrupted around the end of the Nineteenth Century as a result of the popularity of the Impressionists, who were viewed as a rebellion against the academic style of painting. The emotional reaction to the Impressionists' emergence resulted in a total rejection of the Academy and all it stood for, to the detriment of art instruction throughout the Twentieth Century. The techniques taught at the Academy and the ateliers of the Academics represented the culmination of at least five hundred years of more or less continuous development in representational drawing and painting, dating back to the early Renaissance. This wealth of knowledge included many of the discoveries of the Old Masters, yet it was suddenly regarded as "old fashioned," “passé,” etc., and therefore of no further interest. Technical development essentially ceased at that point. Fortunately, a few of the dedicated students of the Academics carried on in obscurity, and passed what they had been taught on to their students.
There was also enough written documentation of the older techniques to enable this author, and a few other similarly obsessed individuals, to gain some understanding of what was involved, undaunted by the best efforts of several universities' art departments to discourage the pursuit of this knowledge. These written clues made possible a more thorough reading of the paintings themselves, sought out in museums across Europe and the United States over many years. Conservation scientists have also been able to provide a considerable amount of extremely valuable information previously only guessed at, which has helped to unravel the mysteries of the past, as technological advances and ongoing scientific inquiry continue to provide an ever-sounder base of knowledge from which to operate. Only after considerable practice in painting can one fully understand what is there to be read in the paintings of the Great Masters and in the books which attempt to explain the techniques.
THE FLEMISH TECHNIQUE
The earliest oil painting method evolved from the earlier discipline of egg tempera painting, as an
attempt to overcome the difficulties and limitations inherent in that medium. As this took place initially in Flanders, the method is referred to as the Flemish Technique. Essential to this method of
painting are a rigid surface primed pure white, and a very precise line drawing. The Flemish painted on wood panels primed with a glue chalk ground, which caused the transparent passages to glow with
warmth from beneath the surface of the paint. As this method did not easily accommodate corrections once the painting was under way, it was necessary to work out the idea for the picture with studies
done on separate surfaces.
The completed drawing was then transferred to the white panel by perforating the "cartoon", or a tracing of it, along its lines, then positioning it over the panel and slapping it with a pounce bag, or sock filled with charcoal dust. The stencil was then removed, and the drawing finished freehand. Another method for the transfer was to cover one side of a piece of tracing paper with charcoal, or with a thin layer of pigment and varnish or oil, which was then allowed to become tacky, and use it as one might use carbon paper. Once the drawing was transferred to the primed panel and completed, its lines were gone over with ink or very thin paint, either egg tempera, distemper (glue tempera), watercolor or oil, applied with a pen or small, pointed, sable brush, and allowed to dry. The drawing was then isolated, and the absorbency of the gesso sealed, by a layer of varnish. Sometimes a transparent toner was added to this layer of varnish, which was then called an imprimatura. The tone of the imprimatura set the key for the painting, making the harmonization of the colors easier, and allowing for more accurate judgment of values. A field of white primer tends to make everything applied to it appear darker than it is, until the white is completely covered, at which time the darks are sometimes seen to be too light. And when the darks are too light, generally the rest of the tones are too light as well. By toning the isolating varnish (a warm tone was most commonly used), to a tone somewhat darker than white, this problem could be avoided or minimized.
Once the isolating varnish or imprimatura was dry, painting commenced with the application of transparent glazes for the shadows. The paints used by the early Flemish practitioners were powdered pigments ground in walnut or linseed oil. There is widespread speculation regarding whether other ingredients, such as resins, balsams, and/or various polymerized oils were added, and the issue is not yet resolved as of this writing. All opinions on this subject must be understood to be guesswork until scientific analyses have been completed on enough paintings from this era to settle the issue. It is likely, though not definitely established, that the brushing characteristics of the paints might have been altered to a long molecular configuration by the addition of boiled or sun-thickened oils, and possibly balsams such as Strasbourg Turpentine or Venice Turpentine, and/or resins. Strasbourg Turpentine, sap from the firs growing in and around what is today Alsace Lorraine and elsewhere in Europe, is similar to Venice Turpentine but clearer and faster drying. Balsams and polymerized oils add an enamel like consistency to oil paint, changing its structure to a long molecular configuration. Long paint is easier to control than short paint, especially with soft hair brushes on a smooth painting surface, as in the Flemish Technique. Brushes used by the early Flemish oil painters were primarily soft hair rounds. Some were pointed at the tip; some were rounded, and some flat. Hog-bristle brushes were also used for certain purposes, such as scrubbing the paint on in thin layers for glazing and other effects. Painting commenced with the laying in of shadows and other dark shapes with transparent paint. In this method, the painting is carried as far along as possible while the paint is wet, but is usually not finished in one sitting. Large areas of color are applied after the shadows are laid in, and worked together at the edges. These middletone colors may be either transparent, opaque, or somewhere in between, depending on the artist's preference. The highlights are added last, and are always opaque. Several subsequent overpaintings may be applied after the initial coat is dry, if desired. Some Flemish artists also employed an underpainting of egg tempera, or egg oil emulsion paint, to help establish the forms before painting over them in oils.
The Flemish method, in summary, consists of transparent shadows and opaque highlights, over a precise line drawing, on wood panels primed pure white. The painting medium may possibly contain a resin and/or balsam, which increases clarity and gloss, or a combination of a polymerized oil with a raw oil, which takes on the most desirable characteristics of a resin when used together (i.e., sun-thickened linseed or walnut oil, plus raw linseed or walnut oil, mixed together), without the defects of natural resins. The innovations are the use of oil paint and the technique of glazing with transparent color. A glossy varnish is applied at least six months after completion. Paintings are generally limited to smaller sizes, due to the difficulties involved in constructing, priming, and transporting wooden panels of greater dimensions. It had its limitations, but was a vast improvement over egg tempera, both in ease of execution and in the beauty of the final result.
Although it originated in Flanders, word quickly spread of the marvels of oil painting, and it was soon adopted by the German artist Albrecht Dürer, who is known to have traveled to Flanders and to Italy, and by Antonello da Messina, who studied in Flanders, according to Vasari. Giovanni Bellini then learned it from Antonello, and taught it to Giorgione and Titian. The Flemish painter Rogier van der Weyden, who was adept at painting in oils, came to Italy around 1449 and influenced a number of Italian artists, including Piero della Francesca. The use of oil as a painting medium was adopted cautiously by some, and derided by others, as anything new always seems to create controversy. Michelangelo refused to paint in oils, and reportedly ridiculed Leonardo for adopting it. Titian (Tiziano Vecellio) recognized its merits, and soon added several innovations of his own.
THE VENETIAN TECHNIQUE
Titian and Giorgione are generally credited with originating what became known as the Venetian
Method of oil painting. The Venetian Method, or Venetian Technique, shares with the Flemish Method the use of transparent glazes for the shadows, darker darks and for certain special effects, and
opaque highlights, but differs from the Flemish method in several important ways.
The method evolved out of necessity, as the church desired large paintings of religious scenes for cathedrals, and wealthy dukes wished to adorn their palaces with large paintings of mythological themes and other subjects. The difficulties of constructing and transporting huge wooden panels influenced artists to seek an alternative. Canvas was soon adopted as the most convenient support for large paintings, as it could be rolled up and delivered, then reattached to the stretcher frame, or another of the same dimensions, at the painting’s destination and hung. However, the rough texture of the cloth created a need for certain adjustments in technique and perhaps in the chemistry of the paints. A new primer was also needed, as gesso (gypsum bound with animal glue) and glue/chalk grounds are brittle, and thus unsuitable for use on a flexible support. After years of experimentation, involving the addition of oil or honey to gesso to render it more flexible, white lead ground in linseed oil became the accepted primer for canvas. The canvas was first given an application of weak glue sizing to render it nonabsorbent, as the linseed oil would have otherwise caused the canvas to rot. The glue sealed the absorbency of the canvas and excluded the oil from the linen or hemp fibers.
The gloss inherent in paints formulated for the Flemish Method was found to be objectionable for large paintings, and Titian seems to have made adjustments to produce a less reflective surface. It is likely he eschewed the use of polymerized oils, balsams and resins, all of which increase gloss, and opted instead for simpler paints ground in raw oil only. Thus the paint would have been of a short molecular configuration, rather than the (presumably) long paints of the Flemish. It was found that stiff, hog bristle brushes worked better with the short paint and rough textured canvas.
The combination of large, stiff brushes, short paint, and the tooth of the canvas made the painting of hard edges more difficult. Sharp edges occur quite naturally in the Flemish Technique, with its smooth surface, long paint and soft hair brushes, whereas the stiff brushes and short paint produced soft edges as a normal result on a coarse textured canvas. Titian (or perhaps Giorgione, who died young), however, apparently found the softer edges more to his liking, and used them extensively, as they gave the effect of being slightly out of focus. The edges could be sharpened selectively, where desired, to call the viewer's attention to an area of greater importance, or to describe an object whose edges were actually sharp, such as a starched collar, sword, or piece of paper or parchment, or they could be left soft in the interest of Selective Focus.
The systematic use of soft and hard edges together gave the paintings a more lifelike appearance, and more closely approximated the visual experience than did the overall use of hard edges, as had been the previous practice. Titian was perhaps not quite as accomplished a draftsman as Michelangelo, who is said to have criticized him for it, so he devised a technique which allowed him greater latitude for corrections. This technique involved the use of an opaque underpainting, with the edges left soft and nebulous to allow for later adjustments where necessary. Once the forms were established to the artist's satisfaction, he would allow the underpainting to dry, while he worked on other paintings. When dry, the underpainting could then be painted over in color, beginning with the transparent glazes for the shadow areas, as in the Flemish Technique, and developed further with opaque passages representing the areas of light.
In the Venetian Technique, color is often applied over the underpainting initially as transparent glazes, which are then worked into, while wet, with opaque pigments. The paint is worked together wet into wet until the desired effect is achieved, or until the paint becomes slightly tacky, at which time it is allowed to dry thoroughly. This process may be repeated as many times as necessary.
At some point, someone, perhaps Titian, discovered that a light, opaque tone, rendered semitransparent by the addition of a bit more oil and/or simply by scrubbing it on thinly with a stiff brush, applied over a darker area produced an effect that could be put to good use. This is what we now call a scumble. It was found that a scumble over a flesh tone would produce the same effect as powder on a woman's face; that is, it made its texture appear softer. This is a useful device when painting women and young people of both sexes. It is also useful for indicating atmospheric density over distance, or atmospheric perspective. Both glazing and scumbling create optical illusions. As such they effectively expand the capabilities of the limited palette of the early painters in oil. It was imperative that they get the most out of the materials they had.
Glazing is the application of a darker transparent paint over a lighter area. The optical illusion created by the light rays’ having passed through a transparent darker layer, bouncing off the lighter surface underneath, then traveling back through the transparent layer to the viewer’s eyes, is unique to glazing, and cannot be obtained in any other manner. A warm glow is created, and the color thus produced appears warmer and more saturated (higher in chroma) than the same pigment applied more thickly and opaquely. The effect, in the darker passages, is that of a shadow seen up close, with no atmosphere between the viewer’s eyes and itself. The rich, golden glow in Rembrandt's dark browns is produced in this way. Rembrandt was influenced by Titian, and is reported to have at one time owned at least one of his paintings. Glazed darks appear darker than opaque darks, because the light rays are allowed to penetrate more deeply into the paint layer, and are thus subjected to a great deal of filtration before reflecting back out to the viewer’s eyes. This effectively expands the value range possible with paints, which are handicapped on the light end of the spectrum by the fact that white paint is not as light as light in Nature. The Old Masters compensated by carrying their darks as far as they could, to create as wide a range of values as possible. This can only be accommodated through the use of transparent paints on the dark extreme. Furthermore, as light contains color, the artist must make the highlights darker than white in order to include color in them. This further limits the value range, and makes necessary the darkening of all tones by a corresponding amount in order to maintain the proper contrast and relationships between each category of light or shadow. Transparent darks allow the expansion of the dark end of the range.
Scumbling is the opposite of glazing. A scumble uses a lighter opaque paint, spread thinly enough so as to become translucent, over a darker passage. The optical effect thus produced is bluer than the paint applied, as the underlying layer is not completely obscured, and exerts its influence on the overall sensation, as has been previously described. It is very effective in softening surface textures, as soft cloth, such as velvet or cotton, or youthful complexions, the surface of a peach, etc., and, as mentioned, for indicating atmospheric haze over distant land planes and in the sky near the horizon. Overcast skies may be scumbled all over, as in Bouguereau’s “The Broken Pitcher.”
There are still more advanced and sophisticated developments of the Venetian Technique. The "semiglaze", which can be either transparent or semiopaque, or anywhere in between, is a very thin application of color to an area of the same value as the paint being applied. Its purpose is to modify the color of a given area after that area is dry, as in the addition of a tiny bit of vermilion to a cheek or nose, and/or to allow subsequent wet into wet painting over an area in which the paint has dried. It tends to soften unintended too-harsh transitions of tone from the previous sitting, if used properly, and thereby adds a higher degree of refinement to the image. It is applied thinly, by scrubbing it on with a stiff brush, after the addition of a small amount of oil or a painting medium to lubricate the dry surface of the area to be repainted. Titian is reported to have sometimes applied glazes and semiglazes with his fingers, or perhaps he was wiping the excess away after having put too much on with a brush. Stippling with a flat tipped brush is a good technique for applying glazes, scumbles, and semiglazes, though other means work very well in skilled hands. As a further development of the Venetian Technique, the underpainting, or certain parts of it, may be executed in opaque color, rather than totally in neutral greys. One popular variation was Venetian Red and Flake White. The underpainting palette should be limited to lean paints (paints with low oil absorption) which are opaque and/or very high in tinting strength. High tinting strength fat paints (paints with high oil absorption) may be used if mixed in very small quantities with very lean paints like Flake White. The objective is to keep the underpainting leaner than the layers applied over it. When dry, the color may then be subsequently modified with glazes, scumbles, and semiglazes, or painted over with opaque color. These steps may be repeated as many times as necessary. The highlights are placed last, applied wet into wet with a fully loaded brush. Impasto is often employed in the highlights, to produce the most opaque passages possible, and to ensure that they remain opaque. Oil paints become more transparent with age. Therefore, in order for the highlights to retain their opacity over the centuries, they must be applied heavily. The illusion thus created is that of direct light falling on a solid surface, ricocheting from that surface to our eyes. It is not actually an illusion, as that is exactly what is happening. Juxtaposed with the transparent shadows, the illusion of depth is thus enhanced.
The underpainting, sometimes referred to as a grisaille if done in greys, should have its darkest passages painted somewhat lighter than the desired final effect, or the superimposed colors will lose much of their brightness and depth . Except for certain special effects, as in the technique of Rembrandt, the texture of the underpainting should be as smooth as possible. Any brushstrokes not smoothed out before the underpainting is dry, or scraped down before painting over, will produce a problem area in the next stage. Artists who prefer visible brushstrokes should decide where to place them in the final stages of the painting, as accents.
The Venetian Technique allows the widest range of possibilities of any oil painting method yet developed. Its systematic use of opaque passages, glazes, scumbles and semiglazes stretches the capabilities of oil paint to the absolute limits, and allows the artist the greatest latitude for adjusting the picture at any stage. The employment of the optical illusions created by glazing and scumbling, combined with the control of edges (selective focus), enables the oil painter who has mastered it to indicate three dimensional reality more convincingly than is possible with any other technique.
Among the Old Masters who used the Venetian Technique in one variant or another were Rembrandt, Franz Hals, Nicholas Poussin, Jacques Louis David, Jean Auguste Dominique Ingres, Jean Léon Gérôme, and many other great Masters whose names are not well known today.
It should be stressed that the wonderful results achieved by the Old Masters and other great painters were attributable, in great measure, to the preparations undertaken prior to their beginning work on the final canvas or panel. The concept for the painting had first to be worked out in smaller drawings, sketches and studies done on separate surfaces, to solve all the problems to the artist's satisfaction beforehand. This accounts for the impression most often conveyed by their paintings, of having been executed without the necessity of corrections. In truth, there were many corrections, but the major ones, at least, were most often solved in the study stage before the painting itself was touched. For very large paintings, the usual practice was for the Master to paint the painting first on a smaller scale to work out its composition, and then turn it over to his apprentices to be transferred to the large canvas by means of a grid. Refer to the sidebar for a more detailed description of the grid method of enlarging a design. In some cases, the smaller painting was done without color, to be used by the apprentices as a guide in applying the underpainting to the large canvas, which process the Master would oversee, and usually correct and complete after the students and/or apprentices had done most of the work. Often many supplemental studies were drawn and painted by the Master, either to aid the assistants in painting the large picture, or to solve some of the problems for himself, in the development of the concept for the painting. This practice is as much a factor in the excellent quality of the works these great painters produced as were the actual painting techniques they used so well.