title: New insight on the underdrawing of 16th Flemish-Portuguese easel paintings by combined surface analysis and microanalytical techniques.
abstract: This paper focusses on the study of the underdrawings of 16th century easel paintings attributed to the workshop of the Portuguese-Flemish Master Frei Carlos. This investigation encompasses multidisciplinary research that relates the results of surface exams (infrared reflectography, standard light photography and infrared photography) with analytical investigations. The surface analysis of Frei Carlos' underdrawings by infrared reflectography has shown heterogeneous work, revealing two different situations: (1) an abundant and expressive underdrawing, revealing a Flemish influence and (2) a simple and outlined underdrawing. This preliminary research raised an important question related to this Portuguese-Flemish workshop and to the analytical approach: Is the underdrawing's heterogeneity, as observed in the reflectograms, related to different artists or is this rather an effect that is produced due to the use of different materials in the underdrawing's execution? Consequently, if different materials were used, how can we have access to the hidden underdrawings? In order to understand the reasons for this dissemblance, chemical analysis of micro-samples collected in underdrawing areas and representing both situations were carried out by optical microscopy, micro Fourier transform infrared spectroscopy (μ-FTIR), scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDX) and micro-Raman spectroscopy (μ-Raman). Taking into account the different possibilities and practical and theoretical limitations of surface and punctual examinations in the study of easel painting underdrawings, the methodology of research was adjusted, sometimes resulting in a re-analysis of experimental results. This research shows the importance of combining multispectral surface exams and chemical analysis in the understanding of the artistic creative processes of 16th century easel paintings.
authors.affiliation: Évora University, HERCULES Laboratory, School of Sciences and Technology, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal.
authors.forename: S
authors.initials: S
authors.lastname: Valadas
authors.affiliation: Évora University, HERCULES Laboratory, School of Sciences and Technology, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal; Évora University, CHAIA-Centre for Art History and Artistic Research, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal.
authors.forename: R
authors.initials: R
authors.lastname: Freire
authors.affiliation: Évora University, HERCULES Laboratory, School of Sciences and Technology, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Cardoso
authors.affiliation: Évora University, HERCULES Laboratory, School of Sciences and Technology, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Mirão
authors.affiliation: Ghent University, Archaeology Department, Sint-Pietersnieuwstraat 35, B-9000 Ghent, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Vandenabeele
authors.affiliation: National Ancient Art Museum, General Directorate of Cultural Heritage, Rua das Janelas Verdes, 1300-001 Lisbon, Portugal.
authors.forename: J O
authors.initials: JO
authors.lastname: Caetano
authors.affiliation: Évora University, HERCULES Laboratory, School of Sciences and Technology, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal; Jose de Figueiredo Laboratory, General Directorate of Cultural Heritage, Rua das janelas verdes 37, 1300-001 Lisbon, Portugal. Electronic address: candeias@uevora.pt.
authors.forename: A
authors.initials: A
authors.lastname: Candeias
keywords: 16th century portuguese-Flemish workshop; Easel paintings; Infrared surface exams; SEM-EDX; Underdrawing; μ-Raman spectroscopy