Portrait of a Man by Juan Bautista Martínez del Mazo

This is "Portrait of a Man" by Juan Bautista Martínez del Mazo, circa 1650, at The Metropolitan Museum of Art. The painting's real secret is a tiny signature, almost invisible against the dark background.

Look at the sitter's eyes, which seem to follow you, and his meticulously groomed mustache. The dark jacket hints at his status, while the play of light and shadow sculpts his face.

Mazo was a follower and the son-in-law of the great Spanish painter Velázquez. He was a master in his own right, known for portraits and landscapes. This painting is a fine example of his technique, closely emulating his mentor's style.

The skill in rendering the background so subtly that a signature can hide within it is remarkable.

Details

Look closely at the background.
Look closely at the background.
His direct gaze and slightly furrowed brow convey a sense of introspection or perhaps mild apprehension.
His direct gaze and slightly furrowed brow convey a sense of introspection or perhaps mild apprehension.
Transcript

He looks directly at you. His mustache is perfectly groomed. The dark jacket suggests wealth. Light and shadow shape his face. Velázquez's follower painted this. Look closely at the background. There is a tiny signature.