Technology Illuminates Language of Ancient Scrolls
Oct. 18, 2013
By David Levin
When the Dead Sea Scrolls were found in an Israeli cave in 1947, many looked as if they had been written yesterday. Others, however, had aged poorly — over nearly two millennia, they had disintegrated into thousands of fragments, most of which were nearly illegible.
“Some of the fragments looked just like shoe leather,” says Greg Bearman, MA’75, PhD’76, a former physicist at NASA’s Jet Propulsion Laboratory who specializes in digital imaging. Since the early 1990s, Bearman has worked with ancient artifacts like the scrolls, developing new techniques to read their faded texts.
Using a narrow band of infrared light, it’s possible to create high-contrast digital images that make formerly obscured text visible.
“Ink and parchment reflect different amounts of light,” says Bearman. “As you start to go farther into the infrared spectrum, you start seeing the parchment in the image get brighter and brighter, but the ink stays the same dark color. You’re essentially adding contrast to the image, so the text starts to pop out from the background.”
Resurrecting ancient texts is not Bearman’s only mission. He’s also developing imaging techniques to track subtle changes in the artifacts over time, helping conservators monitor their physical state.
In 2008, Bearman began working with the Israeli Antiquities Authority to monitor the entire Dead Sea Scrolls collection — more than 20,000 fragments in all. Using an ultra high-resolution digital camera, he captured dozens of images of each fragment, each one using a different frequency of visible and infrared light. Bearman then ran the images through a computer program to look for damage.
“The basic idea is that you create an initial image of a scroll fragment, then do the same thing a few months, or years, later. If you compare the two images using custom algorithms and software, you can tell which parts have changed or darkened over time, even if the change isn’t visible to the naked eye,” he says.
In addition to imaging ancient artifacts, Bearman notes that the process could be used to track changes in valuable artwork as well. Since it requires only a digital camera, a lighting system and a computer, it can be adapted for use in museums to monitor objects on display.
“We know very little about what’s happening to famous paintings like the Mona Lisa and other popular artwork, since conservators rarely want to move them to the lab or let people take samples for study,” he says, “but the sort of imaging we’re doing could provide useful information on those objects by just taking a picture.”