Q. Why do watercolors granulate? How can I prevent--or encourage--this?
A. Granulation is a natural property of certain pigments, such as cerulean blue, French ultramarine, manganese blue, raw sienna and others. The pigment settles out of the binder and water in a wash into the valleys of textured watercolor paper. Sometimes it will settle out on smoother papers, as well. This property can be very useful for some subjects--clouds, beaches, fog and more. It's a good idea to test all your colors for this property by wetting your paper and flowing some color onto the paper, then rocking the paper back and forth to help the pigment settle. (See pp. 44-45 in Exploring Color Revised. Many colors do not granulate, so if you prefer this, test your colors to find them. Usually synthetic substitutes for granulating colors don't have this property.

Q. What are watercolor mediums for?
A. Most of the mediums described below are Winsor & Newton products. A few are available from other manufacturers.

• gum arabic--slows drying; intensifies color; fades less as it dries; covers better ; stains less; creates shine
• ox gall--a watercolor flow medium that breaks surface tension on high-gloss surfaces; eliminates streakiness in gouache; helps spreading in marbling
• masking medium--resistant to water; protects areas on the paper; can be removed with rubber cement pickup; bonds to paper if left on too long
• permanent masking medium--same as above, except cannot be removed at all
• watercolor medium--dries "harder"; more water resistant; harder to lift; glossier when dry; more luminous, intense color; affects colors that react to acid, such as ultramarine
• prepared size--reduces absorbency of paper; easier to lift; resists staining
• blending medium--slows drying time; more "open time" for blending
• lifting preparation--easier lifting of dry washes with damp brush or sponge; primes paper to allow for corrections
• texture medium--fine particles add texture to colors
• granulation medium--gives mottled appearance or enhances granulation of pigments
• iridescent medium--pearlescent or glitter effects when mixed with paints
• Aquapasto--thicker impasto effect; used for coating monotype plates
• Absorbent Ground (Golden)--makes acrylic-coated surface accept paint more like watercolor paper

Q. How can I remove color stains from my watercolor palette?
A. I use the special non-abrasive cleaner for ceramic cooktops on my John Pike palette and a couple of other plastic palettes that were badly stained. Works like a charm! Be sure to wash the palette with soap and water and rinse thoroughly before using it again. There may be a little beading at first, but that seems to go away in time. I know of two other methods. Rub the palette with a soft cloth moistened with mineral spirits or Goo Gone cleaner. Then wash it thoroughly with soap and water.

Q. What is the correct way to use salt in watercolor paintings?
A. For the past twenty or so years sprinkling salt on a damp watercolor wash has been a popular means of adding interesting texture to a painting. The paint is drawn to the salt as it dries and leaves crystal shapes dotted throughout the wash. I used to use this technique occasionally myself, until I noticed what salt water dripping on my garage floor did to concrete after a bad winter! After talking to several technical people in paint manufacturing, I've come to the conclusion it isn't a wise practice if you want your paintings to last. If you're painting for reproduction or other commercial, short-term use, by all means use it to get the effect you want. But to be sure you're using a pigment that will react properly to salt and give the maximum effect, test the color with salt on the same type surface you'll be working on. Otherwise, for a similar effect simply spatter water on a partially dried wash. See Exploring Color p. 44.

Q. How do you achieve a luminous glow in a painting?
A. Use high-key, pastel tints, very clean and bright, surrounded by middle-key (not dark) low-intensity (gray) neutrals. In the illustration I've surrounded yellow and pale red with a grayed violet. Because the violet is complementary to the yellow, the glow of the center is enhanced. This was J.M.W. Turner's method. Avoid hard edges and let the colors blend to enhance the effect of the glow. Here's a demo of this technique. Exploring Color p. 109.

Q. In watercolors, how much water and how much paint do you use to load your brush?
A. If I had a formula for this, I would patent it and get rich quick! Unfortunately, there isn't one answer to this question, just, "it depends." It depends on the paint you're using: if it's richly pigmented, you can use more water without losing the intensity of the color. If it's a weak color, less water would be the rule, if you want strong color in your painting. This is where beginners have a problem with student-quality paints--they have to pile on the color, and the paintings get muddy and chalky very quickly. It also depends on what kind of finish you want in your picture. If you want delicacy and transparency, use more water and transparent pigments. If you want a velvety, rich surface to the painting, use less water and a paint that has less transparency but lots of pigment in it. Browse the techniques faq for more on this question.

Q. Is it okay to use black or white in watercolors?
A. There used to be strict taboos against using black or white, but like a lot of other rules today, things are a lot more relaxed now. My personal preference is purist watercolor, without either black or white, but I've seen marvelous paintings that have both in them. The trick in watercolor is to make these neutrals look like they belong, and this can be tricky, as they have a tendency to come off pretty opaque and may contrast too strongly with the transparency of the transparent watercolors. Keep in mind if you do use them that there are exhibitions that accept only pure transparent watercolors, and you can't enter a painting that has acrylic black or Chinese white in it.

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