Image spectroscopy mapping technique for noninvasive analysis of paintings

AbstractWide-band near-infrared refiectography is a familiar imaging technique for conservators. For many decades it has been the most effective method for providing an extensive knowledge of underdrawings, retouchings and pentimenti. In this study, a narrow-band multi-wavelength imaging (image spectroscopy) system assembled around a lead oxide-lead sulphide (PbO-PbS) vidicon camera is described and applied to the investigation of paintings in the visible and near-infrared regions. A suitable methodology has been set up in order to make the measurements accurate and reliable. The technique has been applied to the detection of different pigments in the sixteenth-century panel painting ‘La strage degli undicimila martiri’ by Pontormo.