Watercolor Techniques: Overlaying Washes (Glazing)
Learning to paint washes is fundamental to watercolor painting. A wash is a watercolor paint diluted with water. You can control the value, or tone, of the wash by controlling the ratio of paint to water – the more water, the lighter the value will be. To cover a large surface with a flat, or even, wash you want to use a large amount of the paint and water mixture to keep the edges blended.You can also overlay transparent washes, also called glazing. Applying a glaze on top of the same color darkens the value. The more glazes you add, the darker the value will become.
It’s important to note that edges can be hard or soft. A hard edge shows a distinct and even line between colors or strokes. A soft edge is a blurred or blended, often indistinct, line between colors or strokes. In watercolor, a hard edge can be achieved by painting wet paint onto a dry surface (wet on dry). A soft edge can be achieved by painting wet paint onto a wet surface (wet on wet).
Overlaying Washes of the Same Color
One way to darken the value of watercolor is to overlay washes. Controlling value is important to be able to define form and create the illusion of depth and space on a two-dimensional surface. This method uses the transparency of the watercolor by overlaying washes of the same color. In this method you allow the paint to dry, and then add successive layers of the same color, letting each layer dry before painting another layer. Each additional layer darkens the value of the color. Note that letting the paint dry between applications leaves a hard edge between layers.
Try overlaying washes with a number of different paint colors and on different papers to see how many layers you can get and how dark a value before the paint and paper start to degrade. Start with a flat wash of your lightest value covering the whole page. After that is completely dry, leave about an inch at the top and cover the rest of the surface with another flat wash of the same color. Repeat that process as you work your way down the surface, leaving part of each preceding layer showing.
Overlaying Washes of Different Colors
You can also overlap washes of two colors to change the tone and hue of the underlying color. The transparency of the top color with the underlying layer creates a third color. With this technique, it is essential to let the paint layers dry before applications to avoid the colors running together. It is also important to know how colors will interact with each other. To test this, we recommend painting a grid of lines. First, paint a vertical line of each color you want to test and let the lines dry. Then paint a horizontal line of each color over the vertical lines. You will see the new color created at the intersection of the vertical and horizontal lines.
Painting the grid will also enable you to see which colors are more transparent and which are more opaque. Watercolors can be transparent, translucent, or opaque.