Thermal Quasi-Reflectography new tool for art historians

Experts tasked with restoring damaged and faded works of art have a new tool in their toolbox: Thermal Quasi-Reflectography (TQR), a process which uses the mid-infrared part of the spectrum to reveal images invisible to the naked eye. (photos)

TQR was used recently to investigate two works of Renaissance art: the Zavattari frescos in the Chapel of Theodelinda and The Resurrection by the Italian Renaissance artist Piero della Francesca. The process revealed missed details and touch-ups missed by earlier restorations.