July 14, 2012
Part of the fresco by the Zavattaris in the Theodelinda’s Chapel, Duomo of Monza (Italy). The artworks, executed between 1440 and 1446 are extremely rich and complex, featuring different fresco techniques, gold and silver decorations and reliefs. Color photography (a), and imaging in the NIR (b), compared to the TQR image (c). (Credit: Optics Express)
When restoring damaged and faded works of art, artists often employ lasers and other sophisticated imaging techniques to study intricate details, analyze pigments, and search for subtle defects not visible to the naked eye. To refine what can be seen during the restoration process even further, a team of Italian researchers has developed a new imaging tool that can capture features not otherwise detectable with the naked eye or current imaging techniques.
The system, known as Thermal Quasi-Reflectography (TQR), is able to create revealing images using reflected light from the mid-infrared part of the spectrum (3-5 micrometers in wavelength). Researchers from the University of L'Aquila, the University of Verona, and Italy's National Institute of Optics in Florence successfully demonstrated the TQR system on two famous works of art: the Zavattari frescos in the Chapel of Theodelinda and "The Resurrection" by the Italian Renaissance artist Piero della Francesca. The researchers detail their work in a paper published June 18 in the Optical Society's (OSA) open-access journal Optics Express.