The shifts in color and/or value of the planes indicate the turning of form. The use of large planes generally requires significant simplification of the forms being depicted, and the artist must make choices concerning which aspects of the form will be emphasized. The shape of each plane can be unique, or the artist can choose to use a particular shape or set of shapes for all of the planes. For instance, only triangular shapes might be used, or circular, or rectangular, etc.

Large planes used to indicate form need not be hard edged. Each plane might be created with a single brushstroke or swipe of a palette knife, and these strokes/swipes might blur into one another. Or each plane can be carefully filled in and each edge between these planes can be blurred or outlined in any number of ways (see Edges.)

Large planes can also be used in purely abstract works that create the illusion of a three-dimensional abstraction.

Featured: Portrait of the Artist’s Mother by Georges Valmier.