relies upon the use of an opaque colored ground
or toned underpainting applied to the canvas before the actual
painting begins. The intended purpose is to provide an overal
foundation for the building up of modeled tonal areas.
By working over a mid-toned underpainting, highlights and
shadows can be economically applied, achieving an immediate
sense of dimensionality. To most sixteenth century painters, the
preferred ground colors were in the yellow ochre to burnt umber
range, although many painters experimented with their own
individual color blends.
The detail shown above well illustrates the imprimatura method
where the use of light-toned pigments have been applied to the
noticeable underpainting beneath.