Home / Glossary / Underdrawing
Glossary · Technical Analysis
Underdrawing
A preliminary drawing made directly on a prepared panel or canvas surface, beneath the final paint layers — the compositional foundation of a painting, invisible to the naked eye but revealed by infrared reflectography.
Technical art history
Beneath the surface
Definition
An underdrawing is a drawing made on the gessoed and primed panel surface before any paint is applied. It typically traces the main compositional outlines — figure positions, major contours, important internal lines — to guide the painter. Media used include:
- Black chalk — the most common in Italian Renaissance practice, including Leonardo's
- Charcoal — soft, easily corrected, absorbed or fixed before painting
- Metal point — a metal stylus that leaves a fine, permanent line in the gesso
- Liquid media — brush and ink or diluted paint, sometimes used for more elaborate underdrawings
Leonardo's Underdrawings
Leonardo's underdrawings, as revealed by infrared reflectography, are notably different from those of his contemporaries. Rather than precise, detailed outlines, his underdrawings tend to be:
- Suggestive rather than definitive — broad indications of mass and position rather than hard contours
- Extensively revised — pentimenti (changes) are common, suggesting Leonardo continued to work out the composition on the panel itself
- In some areas, absent — particularly in background landscapes and some drapery, which may have been painted directly without preliminary drawing