Role of photorefractive holographic interferometry in Impact Assessment Procedure applied to movable cultural heritage

MULTIENCOD

Towards building a Cathodoluminescence (CL) database for pigments: characterization of white pigments

Paintings and painted surfaces are considered to be extremely complex due to their multitude of materials and thus form the basis for particularly intricate Cultural Heritage studies. The combination of Scanning Electron Microscopy (SEM) with Cathodoluminescence (CL) can serve as a powerful tool for the identification of individual pigments. SEM/CL has the potential of identifying both organic and inorganic pigments and can focus on a micrometer or even nanometer scale. The combination with Energy Dispersive Spectrometry (EDS) allows for robust, cross-checked, elemental and mineralogical characterization of pigments. In order to apply SEM/CL in a routine-based way for the identification of pigments, it is necessary to have a robust, open-access database of characteristic CL spectra of pigments. A large project has been undertaken to create such a database, focusing primarily at the pigments, both organic and inorganic, which were most commonly used from antiquity until today. In the present paper, the CL characterization of common white pigments is presented. White pigments were selected, due to their significance and frequency of use, since they were also present on the ground layers or mixed with other pigments in most of the painting layers. More specifically, the CL spectra of samples in pure form of calcite, kaolinite, lead white, zinc oxide, barium sulfate, lithopone and titanium white are presented. In all cases, the CL spectra present characteristic bands, which allow for a secure identification of the pigments. In order to facilitate comparison with other databases, EDS and RAMAN spectra are also presented. Additionally, the effect of weathering on the CL spectra was evaluated, by comparison to naturally and artificially aged samples and to pigments identified on areas of two paintings, of the 19th and 20th c., respectively. Finally, the effect of binding media was also studied, using combination of pigments with four common media: egg yolk, linseed, walnut and poppy oil. Overall, both weathering and binding media appear to cause minor differences in the occurring spectra, without preventing the identification of pigments.Peer reviewe

Role of dynamic holography with photorefractive crystals in a multi-functional sensor for the detection of signature features in movable cultural heritage

This paper is one of a series submitted by the Multi-Encode Project consortium and covers the development of holographic interferometry with dynamic photorefractive crystals. The aim of the first phase of the project is to assess the existing techniques for detection of signatures in various types of artworks. The trademark of our technique is a very high resolution in the fringe pattern. We will show the potentiality of our technique for the present application.MULTIENCOD

Defect growth in model panel paintings by full field interferometry

MULTIENCOD

nZEB criteria for typical single-family home renovations in various countries

OTBArchitecture and The Built Environmen

Applying SEM-Cathodoluminescence imaging and spectroscopy as a new research tool for the characterization of archaeological material

The present work focuses on the application of Cathodoluminescence (CL) spectroscopy for the analysis of different types of archaeological materials and Cultural Heritage artefacts, namely pottery, glass and paintings, and highlights the significant potential presented by this technique.More specifically, in the case of Hellenistic pottery there is evidence that CL panchromatic images can be used to differentiate between glazes of different quality, even when their chemical composition does not present any significant differences. Additionally, archaeological samples could be differentiated based on CL images from chemically and technologically identical authentic replicas.In the case of Classical and Hellenistic glass samples it was shown that the peak positions in the CL spectra vary depending on the sample provenance; however, for statistical relevance a larger number of glass samples from different locations need to be studied to build a reliable provenance database.Finally, preliminary results on the study of paintings demonstrate that the combination of Electron Microscopy with Cathodoluminescence can serve as a powerful tool for the study of production technology, as well as the identification of individual pigments

Multi-sensor evaluation of a wooden panel painting using terahertz imaging and shearography

Cultural heritage objects are increasingly being investigated using advanced non-destructive optical measurement techniques. Holographic and speckle interferometry based instrumentation allow dimensional measurement of objects at the tens of nanometer scale. For the structural diagnostics of artwork, double-exposure techniques are often used to locate defects, delaminations, voids and other structural features. Shearography is a speckle interferometry configuration that uses a close-to-common-path shearing interferometer configuration to give a direct sensitivity to displacement gradient at the object surface. This configuration is particularly useful for measurements outside the optical laboratory, as the stability requirements are much reduced compared with holography techniques. Terahertz imaging is a new category of sensor, used to investigate materials using electromagnetic radiation in the 0.1 to 10 THz frequency range. At these frequencies many materials become semi-transparent, so bulk structural diagnostics can be performed. Typically terahertz imaging is performed using a scanning pixel, or multi-pixel, sensor. In this manuscript shearography is first used to identify areas of interest of possible structural anomalies in the artwork. These regions of interest are then studied in more detail using the terahertz imaging instrument. Together the two instruments provide an analysis of both the surface and bulk structural features. The approach is demonstrated experimentally using a wooden panel painting.Structural Integrity & Engineering MechanicsAerospace Engineerin

Multifunctional encoding system for assessment of movable cultural heritage

This is an introductory paper of a recent EC project dealing with research in cultural heritage and aiming to communicate new fields of application for optical metrology techniques. The project is in its initial state and more conclusive information is expected to be available at the time of the perspective conference. Nowadays safety, ethical, economical and security issues as well as the increase demand for loaning of art objects for exhibitions in transit, are forcing the Conservation Community to undertake strong initiatives and actions against various types of mistreatment, damage or fraud, during transportation of movable Cultural Heritage. Therefore the interest directs to the development of innovative methodologies and instrumentation to respond to critical aspects of increased importance in cultural heritage preservation, among which of prior consideration are: to secure proper treatment, assess probable damage, fight fraud actions in transportation