Remote Reflectance Spectroscopy on the painting ‘Saints Peter And Stephen’ conserved at the Fondazione Giorgio Cini

This study presents a novel approach for remote Fiber Optic Reflectance Spectroscopy (FORS) applied to the Renaissance painting Saints Peter and Stephen, tentatively attributed to Antonio del Massaro da Viterbo. The painting, housed at the Fondazione Giorgio Cini in Venice, was analyzed using both contact and remote FORS, with the latter performed at an 8 meter distance using a custom optical setup inspired by astronomical techniques. The reflectance spectra obtained in both configurations showed strong agreement, enabling the identification of pigments such as iron-based yellows, red lake, malachite, and azurite. The findings offer new insights into the artist’s material choices and techniques, while also demonstrating the feasibility of remote FORS as a non-invasive diagnostic tool for cultural heritage. Future developments will focus on refining the optical setup to further improve measurement accuracy and expand the applicability of remote FORS in heritage science