Smithsonian.com

A mock-up of the multiple layers of Rembrandt’s “Old Man in Military Costume,” photo by Andrea Sartorius via J. Paul Getty Trust.

Rembrandt van Rijn’s “Old Man in Military Costume,” captures a rich history in one portrait. As the painting’s current home, the Getty Center in Los Angeles, describes its subject,

His military costume may symbolize Dutch strength and patriotism during the struggle for independence from Spain. Although he faces front, the man’s torso is turned in a three-quarter view; his watery eyes gazing off to the side give the image a sense of immediacy.

For several decades, though, art historians and scientists have been intrigued by another story embedded within the 380-year-old painting—the artist’s methods.

Using conventional X-ray technology, researchers investigated “a confusing area of greater density” in one area of the portrait, to try to find out whether it was an earlier portait attempt that the artist had painted over. According to the Getty website, by 1984, conservators had discovered that there was, indeed, another figure hidden beneath.

The difficulty of revealing the “underpainting” lies in the fact that Rembrandt used the same type of paint, with the same chemical compound, in both versions. So more sophisticated X-ray technology was necessary.

Now, new experimental methods at the University of Antwerp have the potential to really see what’s hidden underneath the portrait, even if the composition of each layer of paint is the same. Scientists have tested a kind of macro X-ray fluorescence analysis on a mock-up painting they created for the experiment:

When bombarded with these high-energy X-rays, light is absorbed and emitted from different pigments in different ways. The scientists targeted four elements of the paint to fluoresce, including calcium, iron, mercury and lead, and got much better impressions of the hidden painting in the mock-up than they were able to before.

The next step is to repeat the process on the real thing. It’s not the first time a Rembrandt piece has been put through the X-ray scanner—a year ago, the Brookhaven Labs used macro-scanning X-ray fluorescence spectrometry (MA-XRF) to verify that an unsigned portrait from the 1600s was, in fact, an authentic Rembrandt.

Below is a brief talk by a curator at the Metropolitan Museum of Art about Rembrandt’s methods, and what makes “An Old Man in Military Costume” such a compelling masterpiece:

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