by Wendon Blake
You’ll think of plenty of other combinations. But keep your tints pale and stay away from saturated colors. You don’t want to lose the luminosity of the painting surface. Nor do you want the tinted surface to swallow up the colors you put over it. This is why a dusty yellow like yellow ochre is better than a vivid yellow like cadmium. For the same reason, avoid bright pinks, greens and violets, and when you use a vivid blue like phthalocyanine, be sure to add it a speck at a time; this color is so powerful that a little goes a long way.
Preparing Textured Surfaces
You may not only want to alter the color of your painting surface, but also its texture. Acrylic gesso lets you do this with ease.
Let’s take something simple. Painters sometimes wish they had a gritty surface something like sandpaper. To prepare this type of surface, just collect some clean sand from a beach or from your building supplier, paint a coat of fairly thick gesso on a Masonite panel, and then sprinkle the sand on the gesso while it’s wet. When the gesso dries, a fair amount of sand will stick. Dust off the grains that don’t stick. Then paint a second coat of gesso over the sand which has stuck to the first coat. This restores the whiteness of the surface and assures you that your paint will stick.
An important trick in getting an evenly textured surface is to dump on more sand than you think you’ll need. It doesn’t hurt to cover the entire coat of wet gesso with a layer of solid sand; you can then dump nearly all of it into your children’s sandbox and only a very thin layer of sand will stick to the gesso. This is the way to be sure that there won’t be any gaps in the sandy surface.
You can use the same technique with almost any granular substance. The early cubists liked to texture a surface with coffee grounds. I’ve often thought of doing it with oatmeal. Sawdust would work too.
If you’re texturing a large panel, don’t cover the entire surface with gesso and then start sprinkling the sand. By the time you start throwing on the sand, a lot of the gesso will be dry. It’s easier to apply the gesso to an area about a foot square and then sprinkle on the sand. Then go on to an adjacent area and do the same thing. When the entire surface has received its first coat of acrylic gesso and its coat of sand, you can give the whole area its final coat of gesso.
Wood’s Edge by John McIver, A.W.S., acrylic on 300 lb. rough Arches watercolor paper, 22”x30”. This extremely bold use of drybrush exploits the coarse texture of rough watercolor paper. For such effects, handmade paper is distinctly superior to machine-made paper. The heaviest drybrush effects can be achieved with tube color blended with gel medium and just a touch of water. Although, at first glance, the picture seems to be entirely drybrush, the artist has delicately enriched the drybrush tones with washes that move in behind the strokes and integrate the dark and light pattern. (Courtesy Risley’s Gallery, Evansville, Indiana.)
Winter Trees by Victor Ing, A.W.S., acrylic on canvas, 19”x24”. Although canvas is an unlikely surface for traditional transparent watercolor, this material can be very receptive to acrylic watercolor. A fine grained canvas, primed with several thin layers of gesso, can be useful for the type of wet-in-wet painting shown here. The liquid color settles into the fibers of the canvas and takes on the delicate texture of the cloth. It’s often easier to control the random, unpredictable spread of a wet-in-wet wash on canvas than on paper. It’s also easier to wipe away lights and areas that need correcting. In this wet-in-wet painting, the artist has established the general distribution of lights and darks wet-in-wet, then added sharper details, like branches and other growth, when the surface is semi-dry or completely dry. The distant trees are painted on a dry surface, while the foreground growth is stroked into a semi-dry surface and allowed to blur very slightly, but not enough to swallow up the stroke.
4.
Colors and Mediums
When you paint in traditional watercolor, the only medium that you normally add to your color is plain water. Periodically some manufacturer introduces a gel or a paste which can be added to watercolor to alter the brushing consistency of the fluid paint. Occasionally, watercolorists experiment with tricks like adding starch to produce a pastier paint. But such things rarely catch on, and most painters in traditional watercolor stick to a simple mixture of tube color and water.
You can do the same if you paint your watercolors in acrylic; mixed with plain water, acrylic paints behave more or less like traditional watercolor, with the additional advantage that the paint dries waterproof. But you’ll miss the full potential of the medium if you don’t try the various additives that make acrylic the most versatile watercolor medium devised by man. These additives aren’t merely gimmicks, introduced to inflate the manufacturer’s profits. They give you unprecedented control over the brushing qualities of your paint, luminosity of color, drying time, and surface finish.
Gloss Medium
When I described how acrylic paint was made, I explained that the liquid adhesive—the glue that binds the dry color to the painting surface—is a milky plastic emulsion that dries water clear. This emulsion is sold by the bottle. If you brush the pure emulsion, straight from the bottle, on a bit of paper, you’ll see that this acrylic medium dries to an absolutely colorless, glossy finish. As soon as the water in the emulsion evaporates, the microscopic particles of plastic form a tough, durable skin which will no longer dissolve in water.
Now, if you add this milky medium to a blob of tube color instead of adding water, you get a new kind of watercolor. The pasty tube paint dissolves in the medium to form a thick fluid that’s roughly the consistency of maple syrup. For the moment the paint looks a bit milky—not completely transparent—because the medium has a faintly whitish tone when wet. But when this paint dries, it’s every bit as transparent as the purest watercolor wash. Yet the color has a new luminosity, an inner light like a varnished oil painting.
The brushing quality of this fascinating mixture is a bit like oil paint too. It’s thin enough to be applied with a soft sable brush in a smooth, regular coat. But it’s just thick enough to be applied with a stiffer bristle brush, which makes a distinct stroke and leaves the marks of its bristles. Thus, you have the choice of smooth or textured color.
If you’ve painted in traditional watercolor, you’ve probably learned, by bitter experience, that it’s unwise to go back and try to push around a wet passage once it’s begun to settle into the paper. But acrylic medium thickens your paint just enough to give you that vital extra time to rebrush a wet passage and get it right before it dries. The paint still dries quickly, but it remains viscous just a moment longer.
However, you’ll probably find that mixing tube paints with pure acrylic medium makes the paint a bit too thick for most purposes. You’ll find such paint perfect for strong accents and big, rugged strokes—like tree trunks, for instance—but you’ll want somewhat thinner paint most of the time. The trick will be to thin your paint first with water, then add a brushful of medium to get the consistency exactly right. I keep a paper drinking cup filled with acrylic medium right next to the quart jar of water that I use to thin my paint. In this way, I can add the necessary brushfuls of water and medium to make my paint thinner or thicker, as I see fit.
Matt Medium
Traditionally, a painting in watercolor has a matt (non-glossy) surface. Most watercolorists will rebel at the very idea of adding a glossy medium to a watercolor wash, which then comes out looking something like a glaze in an oil painting. Fortunately, acrylic medium comes in two forms: the gloss medium, which I’ve just described, and matt medium, which dries to the non-glossy finish which most watercolorists actually prefer.
The chemical composition and behavior of matt acrylic medium are essentially the same as those of gloss medium, with just one difference: the matt medium contains an inert substance that takes the shine out of the paint. When wet, matt medium looks just as milky as gloss medium, but it dries clear as glass, without any hint that a medium of some kind has been added to your paint. Drying time and brushing qualities a
re the same for both matt and gloss mediums, which have exactly the same consistency and exactly the same effect on the behavior of your paint. In fact, when they’re in liquid form, it’s virtually impossible to tell the difference between matt and gloss medium; the difference shows up only when they dry.
Whether you prefer matt or gloss medium is purely a matter of taste. Gloss medium does seem to add luminosity to your colors, much as a layer of varnish gives a bit more glow to an oil painting. On the other hand, much of the charm of traditional watercolor lies in subtle color and atmospheric delicacy, for which a matt surface may seem more appropriate. The choice is up to you.
Gel Medium
Acrylic medium comes in a third form, called gel. This is thick, pasty stuff which comes in a tube like paint. When squeezed from the tube, it has the same cloudy, milky look as the matt and gloss mediums when they’re still wet in the bottle. But gel medium, too, dries clear.
Gel was developed primarily for painters who want to use acrylic like oil paint. Mixed with tube color, gel keeps the paint stiff and buttery for so-called impasto painting, which generally means a heavy buildup of color, with lots of rough brushstrokes and knife strokes.
Watercolorists, of course, generally deal in thin layers of liquid color. Thus, impasto painting seems to be at odds with the essential nature of watercolor. If you’re using acrylic as a watercolor medium, I don’t think it’s likely that you’ll want to pile on big gobs of color thickened with gel medium. On the other hand, there are some ways in which gel medium can be used to extend the range of watercolor techniques without turning your picture into a gummy pile of paint.
Every watercolorist does have certain moments when he wishes that he had just one or two brushfuls of really thick paint for a passage that needs more than usual texture. I’ve often felt this when I tried to render a particularly craggy rock formation or a particularly rugged tree stump in the foreground. If you don’t overdo it, gel medium is just what you need for these rare moments. Just one dab of gel medium, added to some paint straight from the tube, undiluted with water, and applied with a really stiff bristle brush, and you have a brushful of paint quite unlike anything you can get in traditional watercolor. Yet gel dries absolutely transparent and this transparency will harmonize with the more fluid passages in the rest of the painting.
But I repeat: don’t get carried away with the fascination of this luminous, transparent paste. A few notes of it may be fine, but too much gel and your painting will cease to be a watercolor. At that point, if you really fall in love with gel medium, you’re no longer thinking like a watercolorist, but more like an oil painter; put away your watercolor brushes, get yourself some big bristle brushes and palette knives, and start working on canvas.
Drought by Gene Matthews, acrylic, watercolor, and dry pigment on foil paper, 18”x24”. Because acrylic paint and medium will adhere tenaciously to almost any kind of paper, Matthews has chosen a metallic surfaced paper for his lively landscape study. In the lower right hand corner, you’ll see how the liquid color has formed streaks and beads on the nonabsorbent surface, and this accounts for the fascinating, blotchy, speckled quality of the painting as a whole. It’s worth noting that dry pigment can be mixed with pure acrylic medium to make your own paint, or the pigment can be sprinkled on a wet layer of medium previously applied to the painting surface.
Back Cove, Pemaquid by Norman Kenyon, A.W.S., acrylic on Arches watercolor board, 18”x25”. To render the rich, irregular textures of rock formations like these, you have the option of using acrylic tube color, very slightly diluted with water, or you can develop the right paint consistency by adding matt or gloss medium—or even the much thicker gel medium, which gives you a consistency more like oil paint. Thick acrylic tube color on heavily textured watercolor paper is particularly effective for drybrush passages like the patch of light at the middle of this composition.
Testing Mediums
Before you start painting with these three different acrylic mediums, here are some tests that are worth trying. These little exercises will help you to find out more about how each medium will behave in action.
(1) Gather some scraps of watercolor paper that are too small, too battered, or too dirty to use for anything else. You’ll need plenty of these scraps for this and the following tests.
Now squeeze out a dab of some cheap color–earth colors like burnt umber cost a lot less than the cadmiums—since it’s silly to waste your most costly colors on this sort of thing. Pick up some paint on a sable brush, without any water, and paint a block of color about 2” square. Then pick up another dab of color, thin it with a little water, and paint another block about the same size. Keep repeating this process, thinning your tube color with more and more water, and paint blocks of color that get lighter and lighter.
The whole idea is to see what you get when you use only water as your painting medium. This is what you’d do if you were painting in traditional watercolor, with no matt, gloss, or gel medium. You’ll find that acrylic tube paint does behave like traditional watercolor, with one notable difference: when you paint in traditional watercolor, you use just a touch of tube color and a great deal of water; when you paint acrylic watercolors, you’ll use proportionately more tube paint and less water. This is why tubes of traditional watercolor are so small and tubes of acrylic are so much bigger. A tube of watercolor is much more concentrated: it’s practically all pigment, with just a bit of gum arabic binder. Acrylic paint contains much more binder—acrylic emulsion, that is—which dilutes the pigment and takes up more room in the tube. In both cases, you get about the same amount of color for your money. It’s just that one paint is more concentrated than the other.
(2) Squeeze out some more color and pour a little gloss medium into a paper cup next to your water jar. Pick up a touch of color on a sable brush, then pick up a dab of medium, and mix them together on your palette. Be sure to mix them thoroughly so that no streaks or bubbles of milky medium remain. Then paint another block of color on one of your paper scraps. Now pick up some more color on your brush, some more medium, and this time some water. Mix them thoroughly on the palette and paint another block of color.
Keep repeating this process, adding a bit more water each time, so that the amount of medium in the mixture keeps diminishing.
The purpose of this exercise is to let you examine the effect of color thinned only with medium and then compare this with the behavior of color that’s thinned with varying proportions of medium and water. Then, when you actually go to work on a painting, you’ll know when you want fairly thick paint (thinned only with medium), when you want somewhat thinner paint (thinned with varying proportions of medium and water), and when you want really thin paint (diluted only with water).
It’s also important to get used to the process of combining color, medium, and water. Because you’re dealing with three materials, each with a different consistency, this takes a bit more care than just picking up a touch of watercolor on the tip of your brush and swishing it around with water. You must keep your eye on the paintacrylic medium-water mixture, making sure that it’s thoroughly blended before you apply it to paper.
(3) I recommended that you try the last test with gloss medium. Now do the same thing with matt medium. As I said earlier, you’ll find that they behave in exactly the same way. But they obviously dry to different finishes. Study these finishes carefully and see which one you prefer. If you’ve been brought up on traditional watercolor—like me—you’ll probably prefer the matt medium. But don’t be a conformist. If you really prefer the look of the gloss medium, stick to your guns!
You might want to try a compromise between the matt and gloss mediums. You can produce a semi-gloss surface by mixing matt and gloss mediums half and half in a paper cup. Try thinning your paint with this mixture and see what kind of finish you get.
(4) Now squeeze out a small gob of gel medium on your palette. Using a bristle brush, pick up some tube color and mix this with the gel med
ium. Apply this stiff, pasty mixture to the paper with a quick, direct stroke. Don’t iron the color out. When this dries, you’ll find that you have something which is not only impossible in traditional watercolor, but just as unlikely in oil painting: a transparent impasto. The thick, dried paint will retain the grooves left by your bristles.
Now mix some more color with some more gel medium and paint it on the paper once again. But this time, spread the color out a bit more, dabbing and patting and stroking to produce a variety of brush textures. You’ll find that the paint retains these strokes and textures very precisely, just as oil paint would, and remains transparent.
Now try thinning your mixture of color and gel with just a touch of water. If you don’t add too much water, the paint will take on a bit more fluidity, but will still be stiff enough to retain interesting strokes and textures. However, if you add lots of water—and maybe you ought to try it—you get fluid paint that’s no different from tube color which has been diluted with gloss medium. This obviously defeats the purpose of the gel. If you want paint which is creamy but fluid, you’re better off using gloss or matt medium.