Imprimatura
The imprimatura is a thin, transparent layer of paint—usually a warm, earthy color like raw umber—that artists apply to a white canvas or panel at the beginning of a painting.
Its purpose is to:
Tone down the white of the canvas, which can be too bright and distracting
Unify the colors in the painting
Help judge values (lights and darks) more accurately
It’s like giving the canvas a warm “base coat” before building up the painting in layers.