Term: Underpainting

An underpainting is the initial layer of paint applied to a ground which serves as a base for subsequent layers of paint. Underpainting gets its name because it is normally hidden underneath the finished painting. It can serve several purposes ranging from a simple composition guide to an integral background element visible in the finished painting. It may be a very rough sketch or a finely rendered image. It's chief value is in creating luminescence in the painting, since light reflects through it from the back of the canvas. There are several different types of monochromatic underpaintings, such as verdaccio and grisaille.