Optics for Arts, Architecture, and Archaeology VII最新文献

{"title":"Front Matter: Volume 11058","authors":"","doi":"10.1117/12.2541622","DOIUrl":"https://doi.org/10.1117/12.2541622","url":null,"abstract":"","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"452 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116068399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MID-FTIR macro mapping and clustering-based automatic brushing: an advanced diagnostic tool for in situ investigations of artworks","authors":"E. Catelli, G. Sciutto, S. Prati, R. Mazzeo","doi":"10.1117/12.2526117","DOIUrl":"https://doi.org/10.1117/12.2526117","url":null,"abstract":"Macroscopic mapping and hyperspectral imaging in the mid-infrared region (2500-25000 nm/4000-400 cm-1) are promising technologies in the field of analysis of cultural heritage. So far they have been successfully employed to study paintings and illuminated manuscripts, gathering important information on spatial distribution of artists’ materials. The present paper reports on the application of mid-infrared macroscopic mapping and hyperspectral imaging to the study of artworks. For an exhaustive overview, instrumental details, working principles and image processing methods will be also presented and discussed.","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114367500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Noninvasive depth-resolved material characterisation using OCT and spectral imaging (Conference Presentation)","authors":"Patrick S. Atkinson, C. Cheung, Haida Liang, C. Higgitt, M. Spring","doi":"10.1117/12.2527448","DOIUrl":"https://doi.org/10.1117/12.2527448","url":null,"abstract":"Typically, varnish coatings were applied to Old Master paintings to improve their visual appearance, saturating the colours. However, over time, varnishes deteriorate and discolour, obscuring or altering the appearance of the artwork, necessitating their removal (usually through the use of a solvent) and replacement. Varnish removal presents a degree of risk to the paint surface and may result in loss of original materials or other damage. Thus, diagnostic methods that can support conservators during varnish removal are very valuable.\u0000Optical Coherence Tomography (OCT), a white light interferometry technique based on the Michelson interferometer, has been proposed as an ideal tool for monitoring the cleaning and treatment of artworks and historical objects. This is owing to its ability to provide non-invasive and accurate measurements across the entire surface of an artwork of the stratigraphy of transparent and turbid multi-layered structures.\u0000In many cases, however, difficulties may arise when attempting to distinguish degraded glaze layers on paintings (coloured, translucent layers containing pigments with refractive indices very close to the binding medium) from layers of aged varnish due to similarities in their appearance and scattering properties in OCT scans. In order to mitigate the possibility of damage through the accidental removal of glaze layers, we propose a simple and entirely non-invasive technique to identify the spectral features of a semi-transparent layer using a combination of OCT and spectral imaging in the visible range. \u0000Building on preliminary studies 1,2, the technique utilises an algorithm to automatically obtain the thickness distribution of the surface layers from the OCT volume of a region with relatively uniform pigmentation and colour. This information is then coupled with the spectral data from the same region to derive the spectral characteristics of each translucent surface layer. Such characteristics may then be used to the discriminate between aged varnishes and glaze layers. The potential of this approach has been demonstrated on mock-up samples and paintings from the National Gallery in London.\u0000[1] Lange, R., Liang, H., Howard, H. and Spooner, J., “Optical coherence tomography and spectral imaging of a wall painting,” SPIE Newsroom (2011).\u0000[2] Liang, H., Lange, R., Howard, H. and Spooner, J., “Non-invasive investigations of a wall painting using optical coherence tomography and hyperspectral imaging,” Proc. SPIE 8084, 80840F (2011).","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115329125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unbending light: new computational methods for the correction of 3D effects in scanning XRF (Conference Presentation)","authors":"M. Ganio, Stephen Parsons, S. Parker, M. Svoboda, B. Seales, C. S. Patterson","doi":"10.1117/12.2525038","DOIUrl":"https://doi.org/10.1117/12.2525038","url":null,"abstract":"Scanning macro‐X‐ray fluorescence (XRF) spectroscopy on works of art provides researchers with rich data sets containing information about material composition and technique of material use in a compelling visual format in the form of element‐specific distribution maps. The accuracy of these maps, however, is influenced by the topography of the object, which ideally is two dimensional, relatively flat and able to be placed parallel to the data collection x-ray optics. In reality, few works of art are truly flat. Small nuances in the visualized elemental intensity may be introduced into element distribution maps by the presence of topography, whether the curve of a centuries-old panel painting, the natural warping of works on paper or parchment, or, in the most extreme cases, in actual three dimensional objects. The inability to confidently ascribe a change in signal intensity to actual elemental composition versus topographically-induced variance, therefore, presents a challenge, particularly when attempting to identify markers of artists’ techniques, compare several objects, or overlay/register images from scanning XRF with those from other imaging modalities. \u0000To address this challenge, this paper introduces a new methodology for post-processing scanning XRF data sets to correct for elemental intensity variations as a function of topography. The method augments the acquired XRF data based on a three-dimensional reconstruction of an object and a set of elemental intensity/distance response functions. These response functions act as a calibrated guide for modifying the intensity map based on depth variation. The geometry-based parameters of local surface shape (curvature), distance of the XRF detector from the surface, region of intersection of the incident fluorescence beam with the surface, and the orientation of the incident beam with respect to the surface normal, are each accounted for in the calibration phase as a large set of pre-acquired examples. This provides a mechanism for capturing and understanding the anticipated variations in the macro-XRF data, interpolating the examples in order to smoothly estimate variations, and applying those variations as corrections to macro-XRF data collected on non-planar surfaces.\u0000The acquisition and representation of the macro-XRF variation as a function of the geometry is explained, with an emphasis on understanding the parameters that induce the most severe errors in the XRF estimates. The representational framework for collecting, storing, and summarizing calibration data over a large number of scans is discussed, followed by several proof of concept examples, including data from one of the masterpieces of the J. Paul Getty Museum collection: Mummy portrait of a woman (JPGM #81.AP.42), also known as Isidora. This 1st century Romano-Egyptian funeral portrait on wood was originally included in mummy wrappings, and is therefore curved to match the natural curves of the embalmed subject. An XRF scan of ","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"233 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132959000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scanning the Celts: evaluation of 2D and 3D techniques in protohistoric archaeology (Conference Presentation)","authors":"Charlotte Hochart, Elsa Lambert","doi":"10.1117/12.2527566","DOIUrl":"https://doi.org/10.1117/12.2527566","url":null,"abstract":"","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129627579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of thresholds for safe analyses of acrylic paintings by nonlinear optical microscopy (Conference Presentation)","authors":"M. Sanz, M. Oujja, R. Fontana, R. Cicchi, A. D. Fovo, S. Mattana, M. Marchetti, M. Castillejo","doi":"10.1117/12.2525989","DOIUrl":"https://doi.org/10.1117/12.2525989","url":null,"abstract":"Non-invasive, high resolution 3D analysis techniques are very much sought for the characterization of multilayer, multicomponent substrates, as those often encountered in artworks and objects of cultural heritage. The non-linear optical interaction of ultrashort laser pulses with a substrate is the basis of the various modalities of the non-linear optical microscopy (NLOM) techniques, recently introduced for the study of cultural heritage objects. NLOM relies on near-IR, femtosecond laser excitation of transparent or semi-transparent materials to simultaneously induce, with 3D micrometric resolution, and depending on the optical properties of the sample, multiphoton excitation fluorescence (MPEF) and second and third harmonic generation (SHG, THG) signals. MPEF emission is related to the sample chemical composition, SHG identifies the presence of non‐centrosymmetric structures and THG allows imaging interfaces between optically dissimilar materials. For paintings, it has been recently reported that valuable information about composition, layer thickness and state of conservation can be obtained by NLOM [1-3]. Although NLOM is a non-invasive technique, ensuring a correct analytical protocol requires the determination of the laser power thresholds that allow measurements under safe conditions, an aspect especially important when studying sensitive materials such as paintings.\u0000In this work, we present a novel methodology to determine the laser power thresholds for safe analyses by MPFE of painting layers. We also present the results obtained in a set of acrylic paints, extensively used by artists over the past century thanks to their properties and low cost of manufacture. To that purpose, samples were prepared as thin layers over a glass substrate and MPEF signals were induced with two different femtosecond laser sources: a Ti:Sapphire laser with wavelength of 800 nm, repetition rate of 80 MHz, and pulses of 70 femtoseconds; an optical parametric oscillator pumped by a Yb-based laser with repetition rate of 80 MHz and dual output: at 800 nm with pulses of 100 fs and at 1040 nm with pulses of 140 fs. The excitation wavelength affects the determined thresholds and the results obtained show a strong dependence on the light absorption properties and chemical composition of the painting material.\u0000\u0000[1] Oujja M., Psilodimitrakopoulos S., Carrasco E., Sanz M., Philippidis A., Selimis A., Pouli P., Filippidis G., Castillejo M. (2017) Phys. Chem. Chem. Phys. 19, 22836-22843.\u0000[2] Liang H., Mari M., Cheung C.S., Kogou S., Johnson P., Filippidis G., (2017) Opt. Express 25, 19640–19653.\u0000[3] Dal Fovo A., Oujja M., Sanz M., Martinez-Hernandez A., Canamares M.V., Castillejo M., Fontana R. (2019) Spectrochim. Acta A 208, 262-270.","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127028438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of reflectance-based pigment classification in layered media (Conference Presentation)","authors":"Lionel Fiske, O. Cossairt, A. Katsaggelos, M. Walton","doi":"10.1117/12.2525382","DOIUrl":"https://doi.org/10.1117/12.2525382","url":null,"abstract":"Pigment identification and mapping gives us insight into an artists' material use, allows us to measure slow chemical changes in painted surfaces, and allows us to detect anachronistic uses of materials that can be associated with either forgeries or past restorations. Earlier work has demonstrated the potential of a dictionary-based reflectance approach for pigment classification. This technique identifies pigments by searching for the pigment combinations that best reproduce the measured reflectance curve. The prospect of pigment classification through modeling is attractive because it can be extended to a layered medium -- potentially opening a route to a depth-resolved pigment classification method. In this work, we investigate a layered pigment classification technique with a fused deep learning and optimization-based Kubelka-Munk framework. First, we discuss the efficacy of the algorithm in a thick, single-layer system. Specifically, we consider the impacts of layer thickness, total pigment concentration, and spectrally similar pigment combinations. Following a thorough discussion of the single layer problem, the system is generalized to multiple layers. Finally, as a concrete example, we use the two-layered system to demonstrate both the impacts of layer thickness and dictionary content on paint localization within the painting. Results of the algorithm are then shown for mock-up paintings for which the ground truth is known.","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129209929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel methodology for the automatic analysis of large collections of paintings (Conference Presentation)","authors":"S. Kogou, L. Lee, G. Shahtahmassebi, Haida Liang","doi":"10.1117/12.2527611","DOIUrl":"https://doi.org/10.1117/12.2527611","url":null,"abstract":"The analysis of painting materials and techniques provides important information to history and archaeology research, as well as to scientists and conservators involved in the conservation of objects of cultural heritage. However, the examination of statistically significant number of objects is required to understand the material use typical of a class of objects (e.g. paintings from a certain geographic region, in a certain period, for a certain purpose). This necessitates efficient data collection and the development of methods for their effective analysis. The spectral imaging system developed in our group, PRISMS, enables automated high resolution spectral imaging in the visible/near infrared regime of paintings of any size. The automatic clustering of the spectral reflectance data at the pixel-level can be used for the initial classification of the areas according to their reflectance spectra. In this study, a new clustering algorithm, based on self-organised mapping (SOM), for the sequential automatic analysis of large spectral datasets is presented. The development of such methods makes the analytical procedure more efficient by reducing the number of areas that need to be further examined based on their unique reflectance spectra. The preliminary clustering of the spectral imaging data is supported by the high-resolution x-ray fluorescence (XRF) maps. The multimodal spectral characterisation of the painting materials is completed with the application of high spectral resolution Fibre Optic Reflectance Spectroscopy (FORS) and Raman spectroscopy on each cluster area. Optical coherence tomography (OCT) is used to examine the 3D microstructure of the substrates as well as the painting technique through the examination of the stratigraphy. Examples based on data from collections of Peruvian paintings on paper substrate, Chinese export paintings and Peruvian paintings made in the style of Chinese export painting will be presented.","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131900958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The potential of nonlinear optical microscopy to noninvasively quantify the degradation state of historical parchments (Conference Presentation)","authors":"M. Schmeltz, L. Robinet, Sylvie Thao, C. Teulon, G. Ducourthial, M. Schanne-Klein, G. Latour","doi":"10.1117/12.2527467","DOIUrl":"https://doi.org/10.1117/12.2527467","url":null,"abstract":"","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"141 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124887632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the physical characteristics and chemical composition of gold leaf in works of art by scanning macro x-ray fluorescence (MA-XRF) spectroscopy (Conference Presentation)","authors":"D. MacLennan, A. Heginbotham, M. Ganio, J. Delaney, L. Lee, L. Llewellyn, K. Trentelman","doi":"10.1117/12.2526230","DOIUrl":"https://doi.org/10.1117/12.2526230","url":null,"abstract":"With its intrinsic preciousness, symbolic, and aesthetic connotations, gold leaf was essential to the decoration of artworks from antiquity to the Renaissance. Despite this importance, the physical characteristics and chemical composition of gold leaf in works of art have not, to date, been extensively studied. In this work, case studies from a number of works of art demonstrate the ability of scanning macro X-ray fluorescence (MA-XRF) spectroscopy for in situ, non-invasive examination of the physical characteristics and the elemental composition of historic gold leaf in works of art in different media. Macro-XRF scanning has opened up new avenues of research by providing insight into how these micron-thin sheets of gold were manipulated and applied in individual objects [1,2]. Besides elemental composition, data provided by MA-XRF on gilded objects includes the visualization of the shape, size, and application techniques of individual gold leaves. For example, measurements of the dimensions of individual gold leaves obtained directly from XRF map data of thirteen 14th and 15th century Italian panel paintings reveals differences in the dimensions of gold leaf across different administrative regions throughout the Italian peninsula during this period. This work suggests a deterministic system of leaf production, which varied between the city-states, controlled by the different city guilds. In addition to leaf dimensions, a comparison of the degree to which gold leaves were overlapped during the gilding process reveals important clues about the artistic hand of individual artists. Overlap measurements appear consistent between artworks ascribed to the same artists, even when that artist is gilding with gold leaf of different dimensions, but differ between artworks painted by different artists. Taken together, these measurements advance art historical scholarship by providing a material understanding of artistic practice. In addition to elucidating several facets of the original artistic creative process, XRF maps have also helped identify subsequent interventions, providing new evidence of possible historic conservation or restoration efforts. \u0000\u0000Our knowledge of how gold leaf was manufactured is based on historical treatises rather than material analysis. The ability to confidently detect variations in minor and trace elements in historical gold leaf may provide new tools to better understand dating, location of production, and trades. The suitability and inherent limitations of MA-XRF for the semi-quantitative analysis of the gold leaves, based on a feasibility study using a set of modern gold leaf samples will also be discussed. A ground truth for the concentrations of these, and other trace, elements was validated using inductively coupled plasma-mass spectrometry (ICP-MS). Linear regressions for gold, silver, and copper provide a model for relating XRF intensity to concentration that can be tested on the XRF map data obtained from the historic ","PeriodicalId":169683,"journal":{"name":"Optics for Arts, Architecture, and Archaeology VII","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121173764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}