CERULEAN WHO?

I generally recommend genuine colors over imitations, but there is one impersonator is actually useful.

Imitations, often labeled as “hues,” are economical alternatives to costly authentic colors. They are made from mixtures of inexpensive pigments that approximate the true color. “Hue” versions, however, are rarely as brilliant or clean as the genuine color, and they are always different in character (i.e., lacking the same nuance, not as opaque or transparent, and so on).

Naples yellow is frequently imitated, for instance. Inexpensive cadmium “hues” are popular replacements for highly opaque and powerful cadmium reds and yellows. Cerulean blue “hue” is a less pricey option over real cerulean blue.

Genuine cerulean is an opaque, subtle sky blue. It is a beautiful and useful color, but it is also one of the most expensive. For example, Gamblin’s genuine cerulean currently retails for $35, the highest price point in the company’s line (and even more expensive in some other brands). It’s no wonder, then, that many students choose Gamblin’s more affordable cerulean blue “hue” at just $12.

Cerulean blue is an expensive warm, slightly greenish blue. Inexpensive imitations, which approximate the genuine color, are useful replacements for phthalocyanine blue when the phthalo blue is to be diluted with white paint.

There is a surprise in store with imitation cerulean, though: it is so powerful that it overwhelms other colors it is mixed with.

“Hue” versions of cerulean are typically composed of phthalo blue combined with a touch of phthalo green, plus a lot of white. Even though they are heavily diluted in white, the phthalo colors still exhibit their awesome strength. They are the most potent of all artists’ pigments.

Imitation cerulean is never a good replacement for the genuine article. Nonetheless, it has its uses…as a replacement for phthalo blue. When you intend to use phthalo blue and reduce it with white paint (which is almost always the case), cerulean “hue” can be used instead since it is basically phthalo blue already mixed with white. This means you need not plow through tons of white paint nor take up your time in making phthalo blue paler since cerulean “hue” is essentially a pale phthalo blue.



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FOOD FIGHT!

There are lots of kinds of paints – oil, acrylic, water – along with varieties of each. The serious painter should acquire at least a passing acquaintance with as many as possible. To do otherwise is to deny yourself the opportunity of discovering a form of paint that you might otherwise have developed a passion for.

Toss The Olives

Three sorts of oil paint are made: traditional, alkyd, and water soluble.

The main ingredients in all of them are pigment (the coloring agent) and binder (to hold the pigment particles together and to the painting surface). In traditional oil paints, the binder is usually linseed oil. Binders for alkyd and water soluble oil paints are molecularly altered oils that give the paints distinct performance characteristics.

Several types of oil-based paints are shown. From left to right are Winsor & Newton brand traditional oil paints, Holbein Duo Aqua water-mixable oil paints, and Griffin alkyd paints from Winsor & Newton.

A solvent is used in conjunction with almost every kind of paint. Solvent thins the paint and rinses painting tools. Odorless paint thinner and turpentine are solvents for alkyd and traditional oil paints. Called volatile solvents, since they evaporate rapidly, many individuals are sensitive to their vapors and react to them upon contact with their skin. Water is the solvent for water soluble oil paints.

Each oil paint variant requires its own type of painting medium. Painting medium changes the consistency of the paint, modifies its drying rate, alters its handling characteristics, (usually) adds translucency, and – depending upon the formula of the medium – enhances or minimizes the glossiness of the dried paint.

A wide range of oils and mediums are available for use with oil paints. At left is refined linseed oil, although stand linseed oil, sun-thickened linseed oil, cold-pressed linseed oil, poppy seed oil, and walnut oil are also commonly used. Galkyd painting medium by Gamblin company, on the right, is one of several alkyd-based mediums available from a number of manufacturers. At center is linseed oil that is specially formulated for use with water mixable oil paints.

An oil-based medium is typically used with traditional oil paints, although an alkyd painting medium like Liquin is also acceptable. Alkyd paints perform best with an alkyd painting medium.

Specially formulated oil-based painting mediums are made for use with water soluble paints; these mediums are compatible with water, allowing the artist to avoid the hazards of turpentine and odorless paint thinner. Ordinary linseed oil and alkyd mediums may be used instead with water soluble oil paints; however, once this is done the paints can no longer be mixed with water and volatile solvents must be used to thin the paint and clean tools.

Traditional oil paints dry rather slowly, requiring 24 hours to several days, and a few colors can take as long as a week to dry when applied in a substantial layer. Because they dry slowly, traditional oil paints allow the artist plenty of time to blend patches of color smoothly into one another, employ wet-on-wet techniques, or scrape and wipe paint off the picture to make alterations.

Alkyd paints permit all these same methods to be used, but for a more limited time. Within an hour or so, the paint begins to grow tacky, reducing the ability to freely manipulate it. In about 24 hours the paint is dry-to-the-touch. Many illustrators favor alkyd paints since they handle in a manner similar to oils but dry swiftly enough that the picture can be delivered in a timely manner to meet the client’s deadline. Some painters dislike the slippery and greasy character of alkyd paints (they feel like petroleum jelly).

Water soluble oil paints are a boon to those who want the benefits of painting with oils without the health risks associated with traditional oil painting solvents. They tend to dry more swiftly than traditional oils, usually being touch-dry within a day or two. Water mixable oils cannot be manipulated for as long a period as regular oil paints, growing tacky within a relatively short time. This is particular so when they are mixed with water alone; used with an appropriate painting medium the water soluble oils dry at a more acceptable rate.

A selection of opaque, semi-transparent, and fully transparent colors are available in every type of oil paint (traditional, alkyd, water soluble). Thus, direct painting methods can be used, including impasto, as well as indirect techniques like glazing.

Toss The Custard

Acrylic paints are made of pigment and a polymer (plastic) binder. They can be thinned with water, which is the solvent for acrylic paints, plus a wide assortment of acrylic painting mediums is available.

Acrylic paints are available is a number of forms. Illustrated here, from left to right, are soft body, heavy-body, and liquid acrylics.

Available in several consistencies (Heavy-body, soft-body, and liquid), all acrylic paints dry swiftly, within 5 to 15 minutes. Manipulation of acrylic paint must therefore be carried out with dispatch. Since they dry so quickly, the opportunity to blend colors or work wet-on-wet is severely impeded. Retarders are made that slow the drying of acrylic paints, but the artist still has only a brief period in which to complete any operations. A recently developed product, Open Acrylic paints from Golden Artists’ Materials, remain workable for an hour or more in thin layers, and many hours in thick deposits. This allows oil painting techniques like blending and wet-on-wet to be exploited. Open Acrylics can also be reactivated with water for a limited time after they have dried, resulting in some interesting effects.

Golden’s Open Acrylic paints combine working characteristics similar to oil paints with the rapid drying rate quality of traditional acrylics.

Artists who work with traditional acrylic paints take advantage of the facts that there are no fully opaque acrylic colors and that the paint can be made more translucent with the addition of an appropriate painting medium. Artists exploit this characteristic to thinly layer colors one upon another in the manner of a glaze.

Acrylic paints of all types tend to level out as they dry, and retain little evidence of brush marks. Super Heavy Body by Liquitex, as well as similar products from other companies, is unusually thick and preserves brush and knife marks for those who desire a textured surface. Heavy-body acrylics are the consistency of custard or pudding, and feel and handle somewhat like oil paints. Soft-body paints are similar to the heavy-body variety, but are a bit more creamy and dry to a perfectly flat finish. Liquid acrylics are, as they are labeled, liquid, and remain workable for a reasonable length of time so that they can be manipulated as one would gouache or even watercolor paints.

Toss The Juice

Aqueous paints like watercolor and gouache are composed of pigment with a binder of gum arabic. No special painting medium is necessary, only water, to bring the paint to the desired consistency. Watercolor is available in hard cakes or as a moist paste in tubes. Gouache is always sold as tube paint.

Watercolor paints can be obtained as dry cakes or pans, such as in the compact travel kit seen on the left, or as a moist paint in tubes. At center are tubes of gouache paints.

Watercolors are typically applied in thin, transparent layers of paint well diluted with water; thick passages of paint are avoided. Gouache is basically watercolor paint with a white pigment added to increase the paint’s opacity. In thicker layers it is fully opaque, while in very thin layers it in nearly as transparent as watercolor. All aqueous paints dry rapidly, generally within a few minutes, and can be re-moistened with water to further manipulate them.

Three basic methods are used with watercolor paints. In the direct technique, color is mixed to the degree of intensity desired, painted into the picture, and allowed to stand without further modification. Layering is an indirect method and is carried out by putting down a light wash of color, allowing it to dry, and then painting over it with another thin film of color to adjust the first. For wet-in-wet techniques, the paper is often kept moist to facilitate the bleeding and blending of colors to create soft effects.

When thinned with an abundant quantity of water, gouache can be used like watercolor, except it is not so transparent. The result is a smoky effect when one color is laid thinly over another, particularly when the top layer is paler than the one beneath. When very little water is added to the paint, it can be applied in opaque passages.

Since watercolor and gouache can be reactivated by moistening with water, the picture can be edited at any stage.

Toss The Eggs

In its most basic form, traditional egg tempera is prepared by the artist by combining dry pigment with a mixture of egg yolk (binder) and water (solvent). Prepared egg tempera paints are now offered by a few manufacturers. They are sold in small jars or tubes in a liquid state ready for use.

         

Traditional egg tempera has been in use for thousands of years. Until recently, it was made in the studio by the artist by combining dry pigment (left) with water and egg yolk (center). Only recently have manufacturers discovered how to produce and preserve egg tempera paints that remain moist in the tube for an extended period (right).

Egg tempera dries almost immediately to an absolutely permanent, transparent film. Once dry, it is impervious to most solvents, including water. Pictures made with egg tempera are built up from many layers of transparent paint. Color transitions are effected through control of how those layers are developed. Historically, small soft-haired watercolor brushes are used and the paint is put down in a series of cross-hatched marks in a manner very similar to drawing. Many artists refer to egg tempera painting as drawing with color. Modern practitioners have taken to also using larger brushes and brushes of other materials to spread broad washes of color or to create a variety of textural effects.

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QUESTIONS CORNER

Question:
I have a question regarding used canvas. What do you do with canvas that was previously painted, but you're not happy with the painting? Can you just paint over it entirely? And since different colors have different degree of translucency, would you be able to hide the previous image completely? Or do you think it's not worth the effort to reuse the canvas?

----- Candy Yeung

Answer:
When on a budget (as most of us are), reusing old paintings can save a lot of money. Like you and I today, great masters of the past tried to minimize their expenses, and one way they did so was to paint over their old pictures. In general, however, I don’t recommend painting over old paintings when the new picture is intended for exhibition and sale. But, for studies, sketches, or student works the practice is acceptable and economically prudent.

Old canvases can be resurrected by painting right on top of the old picture, provided the media are compatible. Acrylic and oil paints may be safely applied atop acrylics, but it is not technically sound to work acrylic paint or acrylic gesso over oil paint.

Some artists find it distracting to paint over an old image, and therefore cover it up with white acrylic gesso (in the case of an acrylic painting) or oil paint (if the original picture was done with either oils or acrylics). If this is the route you decide to take, it is recommended that the old painting first be roughed-up by scraping with a palette or painting knife; this will give the new paint a more toothy surface to adhere to. Other artists do not find it disconcerting to paint directly onto an old picture, and some (such as me) actually make use of the underlying color by incorporating it into the new painting.

The artist has painted a new portrait over a rejected earlier one. To execute the new painting, the artist had rotated the original 180 degrees so that remnants of the shoulders of the old figure are now visible at the top of the picture. Turning an old painting upside-down is helpful in reducing the distraction of an old image when painting over it.

There are, of course, drawbacks to either approach. The most obvious is the difficulty of completely obliterating the old image, or at least those parts that interfere with the clarity of the new one.

This canvas has been given a new coat of gesso over the old picture. Note that the coating appears uneven and is gray in places rather than white.

Coating an old picture with white paint or gesso only reduces it to a vague pattern of darker and paler patches, but cannot restore the surface to an even and brilliant whiteness. Whether treated with a white coating or painted directly onto, there may be places where the old picture shows through the new one to an unacceptable degree. In such cases it may be necessary to build up the new paint to a considerable thickness. Keep in mind also that, in oil paints, even the most opaque colors can’t always obliterate what’s underneath, and in acrylic paints there are no truly opaque colors.

There are two other important potential problems with painting over an old picture. The most immediate of these is the surface character of the original painting. Even if the color can be obscured, marks made by brushes and painting knives, along with variations in paint thickness, will still be evident in the new picture and must be taken into account when designing and painting the new image.

Over the long term, there is the issue of pentimento. Paints become increasingly translucent with time and eventually the underlying image will begin to show through the newer picture on top, even when thick and opaque colors have been used. You may have seen this effect in older pictures of interiors where the checkerboard pattern of the tile floor is visible through the figures painted on top. However, if you do not expect your pictures to be admired by future generations, it is not an issue for concern.

Winslow Homer's 1875 painting, Milking Time, is an excellent example of pentimento. Although painted only little more than a century ago, the upper layers of paint have become so translucent that the underlying band of dark, plowed earth is clearly visible through the woman's dress.

Overall, the economic benefits of painting over old pictures frequently outweigh other considerations, particularly for the prolific artist.

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