Print Email Facebook Twitter XRF and RIS for semi-quantitative sub-surface layer detection and composition analysis of easel paintings Title XRF and RIS for semi-quantitative sub-surface layer detection and composition analysis of easel paintings Author de Almeida Nieto, Luis (TU Delft Mechanical, Maritime and Materials Engineering) Contributor Dik, J. (mentor) Alfeld, M.W.E.M. (mentor) van Loon, A. (mentor) Gonzalez, V.M.J.M. (mentor) Gabrieli, Francesca (mentor) Van de Plas, Raf (graduation committee) Degree granting institution Delft University of Technology Date 2020-09-25 Abstract The scientific analysis of historical paintings has been traditionally restricted to the analysis of paint cross-section samples. This invasive method provides extensive information but is inherently limited in scope due to the extreme heterogeneity of paintings. In the last decade, non-invasive spot analyses and spectral imaging methods have become increasingly widespread in cultural heritage science. Two of these methods are macroscopic X-ray fluorescence imaging spectroscopy (MA-XRF) and reflectance imaging spectroscopy (RIS). These methods allow for 2D-scanning the entire surface of a painting and provide complementary information on elemental and molecular composition and distribution of the paint. However, these methods are often used only for qualitative analysis of the paint based on relative distribution maps, revealing only limited information about the paint layer stratigraphy. This thesis is an exploration of a combined approach for quantitative analysis of paint composition and layer stratigraphy using MA-XRF and RIS. The research used a set of specially prepared paint samples of mixtures and multiple layer applications based on historically relevant pigments which were scanned using MA-XRF and RIS in the visible and Near IR range (400-2500 nm). The spectral data acquired were processed and analyzed in a variety of ways, including Non-negative Matrix Factorization, Non-Linear Least Square Fitting, among other methods; in an attempt to gather quantitative compositional and stratigraphic data. In these trials, using characteristic reflectance features in the visible range together with a comparison of highly and lightly absorbed X-ray fluorescence lines allowed for the identification and quantification of surface specific compounds related to the top paint layer. Further comparison of fluorescence lines and absorption features in the Near IR range provided a potential avenue for quantification of subsurface paint layers. The results confirm that the combination of these methods allows to reveal the paint stratigraphy. The project provides samples and data sets which may serve as the basis for the development of a robust algorithm to address this issue in the future. Subject MA-XRFRISPaintingreflectance imaging spectroscopymacro x-ray fluorescenceXRF To reference this document use: http://resolver.tudelft.nl/uuid:d0be5ca1-624b-4774-9327-9d6f6cd3eb48 Part of collection Student theses Document type master thesis Rights © 2020 Luis de Almeida Nieto Files PDF Master_Thesis_de_Almeida.pdf 104.92 MB Close viewer /islandora/object/uuid:d0be5ca1-624b-4774-9327-9d6f6cd3eb48/datastream/OBJ/view