Imaging and spectroscopic data combined to disclose the painting techniques and materials in the fifteenth century Leonardo atelier in Milan

Abstract

The project "Leonardesque Artists beyond the Visible" was planned in the 500 th anniversary of the death of Leonardo da Vinci, with the occasion of an exhibition held in Milan in 2019, where more than twenty works made by Leonardesque masters have been put on display. Among them, five representative paintings made by his closest pupils were selected for a comprehensive and multidisciplinary project. Portable noninvasive imaging and spectroscopy techniques were applied to supply useful information to scholars but also to the wider public: description of the material composition of the pigments, of the preparation and of the binders, existence or absence of underdrawing, and identification of the painters' technique and style. Particular attention was paid also to the image processing techniques, mostly for hyperspectral and radiographic data, to get the most from both innovative and traditional techniques.

FT-NIR Spectroscopy for the Non-Invasive Study of Binders and Multi-Layered Structures in Ancient Paintings: Artworks of the Lombard Renaissance as Case Studies

“…The possibility of detecting the gypsum preparatory layer by the NIR analysis is therefore consistent with what observed on mock-up samples. Similar results were obtained for the "Madonna and Child" by Francesco Galli [38] (Figure 9b), for which gypsum was identified in the ground layer (see also [27]) and it was possible to demonstrate the use of a drying oil as a binder, consistent with the absorbance ratio values (1.4 and 1.7) calculated for two measurement areas (the Virgin's shoulder and her red dress) as an example. As for the "Madonna nursing the Child" by an anonymous painter of the Lombard school [39], the NIR spectra (Figure 9c) indicate that gypsum was not used in the ground layer (see also [14]), in accordance with previous microdestructive analyses [40], while the ratio calculated for two areas of the painting corresponding to the Virgin's blue dress and to the light blue sky (values of 1.7 and 1.9, respectively) still suggests that a siccative oil was used as a binder.…”

“…They were the "Madonna and Child (Madonna of the Rose)" by Giovanni Antonio Boltraffio and the "Madonna nursing the Child" by an unknown Lombard school painter, exhibited at the Poldi Pezzoli Museum in Milan, and the "Madonna and Child" by Francesco Galli, called Francesco Napoletano, stored at the Pinacoteca di Brera in Milan. These masterpieces have already been extensively characterized using imaging and non-invasive spectroscopic techniques, as part of a dedicated project coordinated by the Italian Consiglio Nazionale delle Ricerche-CNR and the University of Milano-Bicocca [27], and the results of FT-NIR measurements reported here were collected during that survey campaign. Two other paintings were examined on the occasion of their restoration, namely "St. Augustine and St. Jerome", painted at the end of the 15th century by Ambrogio da Fossano, known as Bergognone, and belonging to the Chartreuse of Pavia, and "St. John the Baptist", a work by Bernardo Zenale from the beginning of the 16th century and part of a private collection.…”

More than XRF Mapping: STEAM (Statistically Tailored Elemental Angle Mapper) a Pioneering Analysis Protocol for Pigment Studies

“…At this step of data elaboration, nothing can still be said about a few points: 5 and 7 seem to depict an impossible mix of original and modern pigments while, if on one hand 12 and 16 can be excluded from restorations, on the other hand, their similarity with the original areas is so low that any kind of assignment would be a hazard. Following the removal of the K α line of Fe (6.4 keV, Figure 6D), the distinction between original and restoration areas results improved: 1, 2, 3, 4, 6, 8, 9, and 19 can be assigned to recent intervention(s) while 10,11,13,14,15,17,18,20,21,22, and 23 to the Giotto's palette. 12 and 16 are probably two different kinds of reds ascribable to the Florentine master, but their characterization cannot be fully accomplished using the available database.…”

L’analisi Chimica Incontra L’arte E L’archeologia: Una Storia Lunga Due Secoli

“…Si è trattato in particolare della Madonna col Bambino (o Madonna della Rosa) di Giovanni Antonio Boltraffio, della Madonna che allatta il Bambino di scuola lombarda, e del Cristo Bambino di Marco d'Oggiono, appartenenti al Museo Poldi Pezzoli, della Madonna col Bambino di Francesco Galli (noto come Francesco Napoletano), appartenente alla Pinacoteca di Brera a Milano, e di una Madonna col Bambino sempre di scuola lombarda e facente parte di un'ampia collezione privata. Mentre l'opera che dà il titolo alla mostra fu realizzata a tempera, si è potuto così rilevare mediante analisi condotte direttamente nei musei o presso lo studio di restauro che in tali dipinti il legante prevalentemente utilizzato fu senz'altro l'olio, in alcuni casi di lino e in altri presumibilmente di noce, mentre in altri ancora entrambi gli oli furono probabilmente usati in strati diversi dello stesso dipinto [22].…”