WATERCOLOR
Tooth
“Tooth” refers to the roughness of a painting support such as paper. Canvas has a lot of tooth, the rough and absorbent surface grabs the paint right off the paintbrush.
Smooth and glossy paper has very little tooth and it isn’t very good for pastels or charcoal drawing. If you try to draw on glossy paper with charcoal, it won’t accept the charcoal very well. The lines will be very light. Paper made for charcoal drawing has a rougher surface that will accept the charcoal lines and shading.
Sizing
Most watercolor paper has a layer of sizing on it. Sizing is typically made from gelatin. The purpose is to prevent the paint from immediately soaking into the paper. The sizing will allow the paint to sit on top of the paper so you can manipulate it before it dries.
Internal sizing is when they add it to the pulp when the paper is made. External sizing is when the manufacturer applies the sizing to the finished paper.
Cold Press, Hot Press, Rough
Watercolor paper is available in three common textures; Hot Pressed, Cold Pressed, and Rough.
Hot pressed watercolor paper has a smooth surface. When the paper is made, it’s pressed through rollers to smooth out the texture. It’s good for drawing and for creating smooth washes of color.
Cold pressed watercolor paper has a subtle, bumpy texture to it. The texture allows you to create dry brushing effects and pencil lines will have a slightly broken appearance. Cold pressed watercolor paper is probably the most common surface that watercolor artists use. The texture is created by pressing the paper through rollers along with a sheet of felt that impresses the texture into the paper.
Rough paper has the most pronounced texture. It’s made in the same manner as the cold pressed paper, except the felts have a rougher texture.
Different manufacturers create papers with different types of texture. Arches rough watercolor paper is definitely different than Fabriano rough. You have to experiment with different brands until you find one you like.
Wash
A wash is an application of diluted paint. It’s most common in watercolor painting but it also applies to acrylics, inks, etc. You can use water to dilute watercolors and acrylics. Oil paints require a solvent for thinning.
The fluid consistency of the paint allows it to flow more readily. Fluid paint will move around and create interesting patterns by itself. Watercolor artists take advantage of this to create natural looking textures and effects in their paintings.
Diluting the paint with water increases the transparency of it.
Graded Wash / Gradient Wash
A wash that smoothly transitions from one color to another is a graded wash. Being able to produce a flawless gradient will help to improve your paintings. You can use a gradient to paint a sky or a smooth water reflection in a watercolor painting.
An interesting observation is that it’s easier to produce a smooth gradient on rough paper than on a sheet of smooth watercolor paper.
Watercolor Bloom
If you paint into a wash of watercolor paint that’s almost dry, it can create a bloom. A bloom is a pattern that has cloud like shape with rippled edges. The center is usually lighter.
Some watercolor artists consider blooms to be a disaster because they can be quite distracting. Other artists create them on purpose to create random shapes and textures.
Wet Into Wet
Painting into a wet layer of paint is known as “wet into wet.” It’s a common technique that’s applies to most painting mediums.
The benefit of painting into a wet layer is that it creates interesting effects. In oil painting, it creates softer edges and it allows you to blend colors into the existing wet layer. It’s also somewhat more challenging in oils to build wet paint on top of wet paint.
In watercolor, the effects are more pronounced because of the very fluid nature of watercolor paint. A watercolor painting that relies entirely on the wet into wet technique will have soft and indistinct edges.
Granulating vs Staining Pigments
The properties of the watercolor pigments have an impact upon how it behaves on the paper. Larger pigment particles tend to clump together as they dry and it produces a pattern.
Granulating colors stand out more when you paint them over a bright color. The brighter color should be dry first. When you paint over it without a granulating color, the bright color will show through. In the above painting, the Yellow Oxide shows through the darker granulating colors.
Staining colors don’t granulate at all. They produce smooth applications of color. These pigments have a way of staining the paper. If you try to lift them by scrubbing over it with a wet brush to remove some of the paint, it will leave a stain.These pigments are usually transparent and have a lot tinting strength. Staining colors are usually made from organic pigments.
