Nondestructive X-ray fluorescence spectrometry? Fourier-transform infrared spectrometry analysis?
Forget the dense terminology in a recent Getty news release, unless you happen to be a conservation scientist. For everyone else, here’s the latest scoop from the Getty Conservation Institute: Scientist Dusan Stulik, researcher Art Kaplan and photographic conservator Tram Vo have developed a new way to authenticate historic photographs.
Instead of relying on human eyes and microscopes to date photographic images, as in the past, the Getty specialists devised a scientific method that can determine the age of many photographs made in the 20th century. The key, they discovered, was to identify hidden chemical “signatures” associated with particular processes.
In the course of a long-running study, the Getty group analyzed thousands of photographs made by processes involving silver, gold, platinum, iron, barium, strontium and traces of other materials. Taking precise measurements of barium and strontium proved to be most productive because those two metallic elements were used in mineral coatings applied to photographic paper from the end of the 19th century until the 1970s — but in concentrations that varied according to the manufacturer and time period.
The discovery is likely to be a boon to many collectors, curators, conservators and historians, but the first practical application took place in Paris. Working with several French organizations, including the Henri Cartier-Bresson Foundation, Stulik and Kaplan recently performed a chemical analysis on Cartier-Bresson’s original photographs. It’s the first step in building an archival database of the artist’s work, to be used as a basis of comparison for dating other vintage prints by Cartier-Bresson — and for exposing forgeries.
— Suzanne Muchnic
From The Los Angeles Times