Development of integrated innovative techniques for paintings examination: The case studies of The Resurrection of Christ attributed to Andrea Mantegna and the Crucifixion of Viterbo attributed to Michelangelo's workshop

This paper presents the contextual use of Pulse-Compression Thermography and Hypercolorimetric Multispectral Imaging for the diagnostic study of historical heritage paintings. The comparison and the integration of images provided by the two techniques allows the conservation state of both the painting layers and wooden support to be investigated. Relevant information on the painting technique and figurative scene can be obtained as well. The proposed approach was applied to two Italian Renaissance panel paintings. The first object tested was a 16th century panel painting representing a Crucifixion, exposed in the Museum of Colle del Duomo in Viterbo, Italy, and attributed to the workshop of the master Michelangelo Buonarroti. The second artwork was a late 15th century panel painting, representing The Resurrection of Christ, currently preserved at Museo Carrara in Bergamo, Italy, and recently re-attributed to Andrea Mantegna; it was identified as being the upper half of a whole composition together with the Descent into Limbo painting. HMI acquisitions and digital image processing tools allowed to investigate the upper painting layer, while PuCT imaging data gave relevant information on the structure of the wooden support proving to be an innovative stratigraphic investigation method. The combination of HMI and PuCT imaging techniques supplied information on the whole structure of the artworks, identifying surface degradation, different layers, wood defects and their position in the inner layers of the object. The integration of the above-mentioned techniques might stand as a new reference diagnostic method to evaluate conservative needs and support decisions for restoration.