Image of an artist

In late 1995, a dazzling scheme of art fraud finally came undone when Scotland Yard police arrested John Myatt, a painter turned forger, and John Drewe, the mastermind who passed off some 200 paintings and drawings as the work of modern greats such as Marc Chagall, Alberto Giacometti, and Jean Dubuffet. Some experts now fear that many of the portraits and surrealist art attributed to Giacometti on the market are fake. These fears are in keeping with the estimate that 10% to 40% of pictures by significant artists are bogus or so overrestored as to make them the equivalent of forgeries.

The scam was widely reported in the British press and New York Times, and was the cause of much financial loss and embarrassment in the art world, where galleries and museums have a great stake in the credibility of their holdings and sales, along with a notorious reluctance to open their art to these kinds of challenges. The scam was especially embarrassing because, upon examination, much of the fraudulent art was clearly poor imitations-many Giacomettis were done with vinyl paint and K-Y jelly-but both collectors and sales agents were hungry for the transactions and the art market was booming.

For collectors of modern art it should be relatively straightforward to establish the provenance or verifiable history of recent artwork. At least that was the assumption until it was revealed that Drewe had manufactured believable histories for most of the paintings by doctoring primary sources in the art archives of major museums. After almost a decade of success, Drewe and Myatt were finally caught after the estates of several painters challenged some of the art for sale and others in the art world alerted police of their suspicions.

Artwork has long been a target for forgery, of course. Roman artisans imitated Greek sculptors, and apprentices of artists like Michelangelo and Rembrandt often finished their work or generated similar “original” pieces.

Two paths are taken to determine whether a work of art is “real”: authentication, which is a qualitative task based on provenance and expert opinion; and forgery detection, which usually involves physical examination by light microscopy; x-rays, UV, or IR techniques; Raman spectroscopy; or isotope analysis. Science has proved better at discovering the fakes than it has at establishing authenticity. Recently however, digital imaging techniques have been combined with increased computational power to begin creating a science for art authentication.

Authenticating paintings and drawings from high-resolution digital scans has been a project for Hany Farid and his colleagues at Dartmouth College (Hanover, NH).1 Their work is a continuation of research on digital imaging forensics2 and, according to Farid, is a natural successor to the mathematical techniques used for handwriting analysis, characterizing the unique lines and curves of an artist’s technique in drawings or paintings.

The researchers evaluated these attributes by classifying the spectral responses of the images of paintings and drawings using wavelet analysis. They worked from high-resolution digital images of 13 drawings attributed to the Flemish artist Pieter Bruegel the Elder (1525-1569) and one painting by Italian master Perugino (1446-1523). Their results confirmed the verdict of art experts at the New York Metropolitan Museum of Art that eight drawings are authentic and five are imitations. Analysis of the six faces in the Perugino painting suggests that the work was completed by at least four different artists, presumably Perugino and his apprentices.

Farid makes it clear that he did not develop this technique with the motivation of using it in the hyped-up fine art market, with its commercial pressures and threats to authenticity. Still, he’s fascinated by the response he has gotten from the media, which seems to love pitting art against science. A little authenticity might have an interesting impact on the market, and could change how we value artists who are not who we thought they were. As Farid points out, Jacob Savery (1545-1602) was one of the “imitators” of Breugel who was unmasked-or “discovered”-and went on to become famous, and very collectible, in his own right.