Glazing is a term for layering or stacking color, for instance think of different sheets of colored glass or tissue paper one stacked on top of the other. You are able to see through the transparent layers to the ones below, glazing in watercolor is the same idea but instead using thin washes of transparent color. For the cleanest color mixing and purest glazes use only the most transparent color. The reason is these colors allow light to pass through and reflect off of the papers surface leaving beautiful jewel-like effects.
Here are only a few of the transparent colors you may want to consider, New Gamboge, Indian Yellow, Winsor Red, Alizarin Crimson, Carmine, Permanent Rose, Quinacridone Magenta, Winsor Violet (Dioxazine), Indanthrene Blue, French Ultramarine, Cobalt Blue, Antwerp Blue, Prussian Blue, Viridian, Winsor Green (Yellow Shade), Perylene Green, Hooker’s Green, Permanent Sap Green among others.
More opaque the colors have a greater coverage and are useful to tone down color mixtures but they can easily flatten a wash, leave a chalky residue or even give a muddy appearance. Some suggested colors you may want to avoid when glazing are the cadmiums, cobalt’s or other earth colors. Such as cadmium yellow or red, Cerulean Blue, Manganese Blue Hue, Cobalt Turquoise, Cobalt Green, Naples Yellow, Yellow Ochre, Sepia and Indigo.
Why Glaze (or Layer)
Watercolor always dries lighter, 10% when applied to dry paper and 25% when applied as a wash. If you try to speed up the process without building layers color can appear weak and wimpy, glazing helps to deepen or modify color and change the colors hue. This very effective technique can give paintings the illusion of depth, for instance in landscapes it helps to give the impression of and distance with different layers and multiple shading such as in the leafs of trees and grasses. It also gives the impression of light and luminosity such as in skies or the delicate glow in a petal. Glazing like so many other techniques gives a degree of excitement with its unpredictability, and can be very rewarding.
How to Glaze
Each layer must be completely dry before the next is applied, remember you are stacking multiple layers of color and if you apply the next layer too quickly you can easily lift the previous layer and mix it into the current one ruining the effect, and depending on the colors you have chosen possible turning the color into mud. How you check if a wash is ready for the next application is to touch it with the back of your hand and if it is cool to the touch it is still too damp. Another thing when using this technique is that to use soft brushes because if the brush is too stiff you can easily lift color and end up with unwanted brush lines.
How many layers is enough?
Every artist will have a different approach and idea of how they will want to use this technique; some artists like to use up to 50 – 100 very thin layers of color, which usually entails covering the entire sheet with multiple washes. This technique is very time consuming but the results are beautiful and can be well worth the effort, many of these paintings focus on larger shapes of glazed color (such as a sky) with minimal subject areas.
Other artists like myself just don’t have the patience for that many layers and are quite satisfied with much less, approximately 3-4. Here the wash instead of being applied to the entire sheet is limited to selective areas and by localizing these spaces I am able to get rich color depending on how much water and color is used.