3D Photogrammetric Survey, Raking Light Photography and Mapping of Degradation Phenomena of the Early Renaissance Wall Paintings by Saturnino Gatti—Case Study of the St. Panfilo Church in Tornimparte (L’Aquila, Italy)

Abstract

This paper provides the results of a 3D photogrammetric survey of the apsidal conch of St. Panfilo Church in Tornimparte (L’Aquila, Italy). The images were acquired and then processed in order to obtain a three-dimensional model available on Sketchfab platform. The five panels and the vault of the apsidal conch were exported from the 3D model as orthomosaics and then imported into CAD software for the mapping of the main degradation phenomena. The examined surface was almost entirely covered by mural painting and restoring mortars, the latter mainly located in the lower part of the apsidal conch. The whole surface of the apsidal conch was also examined by means of raking light that enabled highlighting of conservation problems and the presence of incision marks and giornata/pontate boundaries indicating the use of the fresco painting technique. Several degradation phenomena, attributable both to the executive technique of wall painting and the microclimate conditions, could be observed. According to the overlapping of weathering forms and the material involved, most of the examined surfaces exhibited moderate to very severe degradation.

Special Issue: Results of the II National Research Project of AIAr: Archaeometric Study of the Frescoes by Saturnino Gatti and Workshop at the Church of San Panfilo in Tornimparte (AQ, Italy)

“…The RAK photos [21] as well as the images acquired with imaging techniques [17] show the presence of incision marks (with minor pouncing) and the boundaries of "giornate" and "pontate", which clearly suggest the use of the fresco painting technique, although in several areas the colour spread was "a secco" [19,24,25], especially where colour loss is observed. The presence of a "morellone" layer under the blue-sky background for the scene depicted on panel E and under the vault confirms the use of the "a secco" painting technique [16].…”

“…With a view to supporting the work of the restorers, 3D photogrammetry, raking light documentation and mapping of the degradation phenomena affecting the painted surfaces of the apsidal conch were performed [21]. This fundamental step supplied relevant information on the conservation conditions, on the execution techniques and on the materials, but also helped in the selection of the points for sampling to perform subsequent laboratory analysis.…”

“…The strong synergy between the in situ/non-invasive analyses [16] and the imaging techniques survey [17,21] performed on the same pictorial areas allowed an analysis of the quality of the punctual analyses results, demonstrating how a well-designed non-invasive campaign can drastically reduce the amount of sampling [18,19,24,25] necessary to obtain complete information on the materials and the artist's technique.…”

Analytical Evaluation of Laser Cleaning Effectiveness in the Context of Contemporary Muralism

“…Raking Light Photography is a crucial yet straightforward technique for evaluating the topographic features of a surface and revealing surface irregularities and textures not visible under normal lighting conditions. In this technique, the sample surface is illuminated from one side in the visible spectrum at an oblique angle, enhancing the surface texture by contrasting illuminated and shadowed areas [28].…”

Application of Sonic, Hygrometric Tests and Infrared Thermography for Diagnostic Investigations of Wall Paintings in St. Panfilo’s Church

“…SPV and HT investigations were performed on the frescoed walls of the apsidal conch of St. Panfilo Church, selecting four areas (panels A, B, D, and E), widely described in [20].…”