The quality of individual portraits is variable; they were often produced in many versions with varying degrees of help from his assistants. In his best works, Pantoja introduced an impressive combination of sophistication and geometric abstraction achieved by means of powerful contrast of light and shadow. His portraits are noted for the meticulous detail of representing the intricate embroidery of dresses and jewelry designs. The subject is usually portrayed standing against a dark background. The face and hands are depicted with a more flat and subtle technique. Among his portraits are: Philip III, Queen Margarita of Austria, 1606, Prado, Madrid). Infanta Isabel Clara Eugenia (1599), Alte Pinakothek, Munich. (Duchess of Braganza, 1603, col.; Unknown lady, col. Marquess of Viana; D. Diego de Valmayor, 1605, Hermitage, St Petersburg.