This PDF file contains the front matter associated with SPIE Proceedings Volume 8790, including the Title Page, Copyright information, Table of Contents, and Conference Committee listing.

In 1973 The Center for Art Conservation Studies (CASS) was established at the University of California, San Diego (UCSD). This was in response to demonstrations that were conducted during January-March 1972 in Venice for UNESCO, Venice in Peril, International Fund for Monuments, and the Italian Petroleum Institute (ENI). The feasibility investigation explored in-situ pulsed holography, holographic interferometry, and laser ablation divestment for applications in art conservation practice. During subsequent decades scores of UCSD graduate and undergraduate students as well as conservators, conservation scientists, academics, and engineers who resided in CASS as “Visiting Scholars” contributed to advancing the understanding and performance of radiation technologies in the arts. Several technologies in addition to those involving optical wavelengths were also investigated to aid in art conservation and conservation science. Magnetic Resonance Imaging (MRI) and Nuclear Magnetic Resonance (NMR) were employed to detect and map moisture within masonry. Lead isotopic analyses revealed authenticity and provenance of Benin bronzes. Inside-out x-ray radiography facilitated the detection of defects in stone. Ultrasonic imaging was introduced for the mapping of fresco strata. Photoacoustic Spectroscopy (PAS) was used to characterize varnish layers on paintings. Digital image processing was introduced in order to detect and visualize pentimenti within paintings as well as to perform virtual restoration and provide interactive museum displays. Holographic images were employed as imaginary theater sets. In the years that followed the graduation of students and the visits of professional collaborators, numerous other applications of radiation ablation began appearing in a wide variety of other fields such as aircraft maintenance, ship maintenance, toxic chemical remediation, biological sterilization, food processing, industrial fabrication, industrial maintenance, nuclear decontamination, dermatology, nuclear weapons effects simulation, and graffiti control. It was readily apparent that the customary diffusion of advanced technologies from science and industry into the art conservation field had been reversed. In this paper we trace the migration and adaptation of radiation divestment developments in art conservation to numerous applications in science, industry, and consumer products. Examples described include the robotized hybrid “Flashjet” aircraft paint stripping system, the “Novotronic” anthrax remediation installation in the Pentagon Building, the InTa automated graffiti removal system employing a carbon dioxide TEA laser, the Bellalite body hair removal product incorporating flashlamp technology, and the Foodco line of optical radiation products for the sterilization of food products. The Foodco products are also applied to the sterilization and/or pasteurization of beverages and beverage containers. A similar device has been adapted to seafood irradiation in order to increase shelf life, as well as for the ablative removal of skin and scales. The Goodyear Tire and Rubber Company, to etch logos and identification information into the sidewalls of pneumatic tires, also developed a flashlamp-based ablation technology. The founders of the CYMER Corporation applied UV irradiation technology to the manufacture of high-performance integrated circuits (viz., memory chips, etc.) In several instances former CASS students and Visiting Fellows consciously adapted the above-learned art conservation methodologies to still other purposes. Thus, these examples of technology transfer may be termed: “Art in the service of Science.” Alternatively, it is evident that many associated innovations developed from independent activities, unconnected serendipity, or through the normal diffusion of information and knowledge across disciplines.

A systematic study on the use of Chlorophyll Fluorescence (CF) imaging in Pulsed Amplitude Modulated (PAM) for assessing viability changes of biodeteriogen on stone artifacts has been carried out. The experimentation has been performed on different phototrophic organisms of gravestone slabs from the monumental British Cemetery of Florence (Italy). Since the viability of these organisms and then their chlorophyll fluorescence emission is strongly dependent on the environmental conditions, a preliminary study on the effects of local patterns during the season was carried out. The trend of the fluorescence quantum yield (QY_max) at different dark adapted times in different periods of the year was determined. The results achieved in our work proves the effectiveness of the CF-PAM imaging for in situ lichen characterizations in conservation studies and defines an optimized application protocol.

For the society it is of great interest to make cultural heritage accessible to the general public. The subsequent increase of museum loan services increases the risk of accelerated degeneration. Hence, in addition to the age related deterioration, transportation can be another source of damage. Despite modern packaging technologies, vibrations and environmental climate change can add up and damage the transported object. Besides obvious mechanical influencing quantities, a main concern is the detection of climate induced damages. Changes in the relative humidity cause inner strain, which may lead to defect formations and damages. White light fringe projection was applied to detect object changes due to variations of the relative humidity. First measurements indicated a sensitivity down to a relative humidity change of 6 %. Recently, the Stuppach Madonna, a painting by Matthias Grunewald (painted 1514 - 1516), was investigated with shearography after the return from an exhibition. The obtained shearograms revealed a variety of defects like bubbles, delaminations and tunnels caused by wood worms. Even the planking of the wooden panel and existing putty could be detected. This paper describes the first steps of a project with the aim of investigating and implementing a method to detect and classify transport related damages on works of art.

This paper describes the preliminary results of a study of the paint layers in 17th-century paintings belonging to the collection of the Wilanow Palace Museum. The works chosen for examination are of great importance to the Museum, as they might have been painted by court artists of King John III Sobieski. The aim of the study was therefore to determine the technological structure of the paintings, to determine the scope of conservation interventions and, above all, to gather comparative material that would serve to conduct further multidisciplinary attributive research. The presentation relates to studies in which laser-induced breakdown spectroscopy (LIBS) and optical microscopy were used as diagnostic tools. LIBS is based on the evaporation of a small amount of the material under investigation, and the generation of plasma which emits continuum and line radiation. The analysis of line radiation allows us to identify the elements appearing in the sample being investigated. The microscope pictures were taken using a Bresser Digital Hand Micro 1.3Mpx and the Hirox 8700 microscopes. The results obtained have confirmed the utility of the LIBS method in the study of artworks. They have also proven that it can be used as a method to complement microchemical analysis, as well as an method to identify and examine artworks from which samples cannot be taken, as it is micro-destructive and the analysis can be conducted directly on the object, without the need to take samples.

Deterioration of artwork, in particular paintings, can be produced by environmental factors such as temperature fluctuations, relative humidity variations, ultraviolet radiation and biological factors among others. The effects of these parameters produce changes in both the painting structure and chemical composition. While well established analytical methodologies, such as those based in Raman Spectroscopy and FTIR Spectroscopy require the extraction of a sample for its inspection, other approaches such as hyperspectral imaging and 3D scanning present advantages for in-situ, noninvasive analysis of artwork. In this paper we introduce a novel system and the related methodology to acquire process, generate and analyze 4D data of paintings. Our system is based on non-contact techniques and is used to develop analytical tools which extract rich 3D and hyperspectral maps of the objects, which are processed to obtain accurate quantitative estimations of the deterioration and degradation present in the piece of art. In particular, the construction of 4D data allows the identification of risk maps on the painting representation, which can allow the curators and restorers in the task of painting state evaluation and prioritize intervention actions.

In recent years Hyper-Spectral Imaging (HSI) technologies have become well-established for applications in the field of Cultural Heritage, and in particular for non-invasive analysis and high quality documentation of paintings and other polychrome surfaces. This paper reports on the latest developments of the on-going research at IFAC-CNR, where a new prototype of a high-performance hyper-spectral scanner, operating in the NIR spectral region (900-1700nm range), was designed, assembled and tested. This new NIR scan-head was designed to be mounted on the same mechanical structure used for the earlier IFAC-CNR scanner prototype, which operated in the 400-900nm range. As ultimate goal the whole system would be intended to provide 2D hyper-spectral data on the extended 400-1700nm range, so as to strongly improve the capability of pigment discrimination, and to increase the possibility of visualizing the underlying features of the polychrome surfaces (such as under-drawings, pentimenti, etc.). In the present version, the NIR scan-head operates with a spectral sampling rate of about 2 nm, and a spatial sampling rate of about 9 dots per millimeter. The results of testing and characterization of the new high resolution NIR IFAC-CNR scanner are presented, with a focus on the main technical problems tackled in customizing the new system for the investigation and documentation of paintings.

As high-resolution conservation images, acquired using various imaging modalities, become more widely available, it is increasingly important to achieve accurate registration between the images. Accurate registration allows information unavailable in any one image to be compiled from several images and then used to provide a better understanding of how a painting was constructed. We have developed an algorithm that solves several important conservation problems: 1) registration and mosaicking of multiple X-ray films, ultraviolet images, and infrared reflectograms to a color reference image at high spatial-resolution (200 to 500 dpi) of paintings (both panel and canvas) and of works on paper, 2) registration of the images within visible and infrared multispectral reflectance and luminescence image cubes, and 3) mosaicking of hyperspectral image cubes (400 to 2500 nm). The registration/mosaicking algorithm corrects for several kinds of distortion, small rotation and scale errors, and keystone effects between the images. Thus images acquired with different cameras, illumination, and geometries can be registered/mosaicked. This automatic algorithm for registering/mosaicking multimodal conservation images is expected to be a valuable tool for conservators attempting to answer questions regarding the creation and preservation history of paintings. For example, an analysis of the reflectance spectra obtained from the sub-pixel registered multispectral image cubes can be used to separate, map, and identify artist materials in situ. And, by comparing the corresponding images in the X-ray, visible, and infrared regions, conservators can obtain a deeper understanding of compositional changes.

The development of a reliable algorithm for 3D reconstruction of jewel surfaces and the relative accuracy evaluation, are the main issues of this paper. They rely on the estimation of the depth and 3D shape of an object from a sequence of images taken at different focus settings (shape from focus). Assuming the focal plane be identified by the best local sharpness, it turns out that the criterion for sharpness evaluation is crucial for obtaining an accurate 3D reconstruction. We present for the first time a novel algorithm for sharpness evaluation, which is based on a particular combination of sum of square differences (SSD). The images processed with SSD have been captured using a novel homemade microscope prototype. The implementation of this technique allows computing the best-focus map (and, consequently, image) from the whole set of images. The assessment of the 3D reconstruction quality has been carried out by considering the structural similarity index (SSIM), since thanks to its effectiveness in measuring the quality of natural images distorted by a large variety of biases. Hence, the novel algorithm has been applied to study micro-morphological features of a modern replica of an Etruscan gold jewel. The granulation ornament on the jewel has been characterized through a geometrical model which can be introduced to illustrate the grains solder quality. The developed geometrical model has been used to analyze also the granulation on an original Etruscan bauletto earring.

Climate Change is one of the most critical global challenges of our time and the burdened cultural heritage of Europe is particularly vulnerable to be left unprotected. Climate for Culture2 project exploits the damage impact of climate change on cultural heritage at regional scale. In this paper the progress of the study with in situ measurements and investigations at cultural heritage sites throughout Europe combined with laboratory simulations is described. Cultural works of art are susceptible to deterioration with environmental changes causing imperceptibly slow but steady accumulation of damaging effects directly impacted on structural integrity. Laser holographic interference method is employed to provide remote non destructive field-wise detection of the structural differences occurred as climate responses. The first results from climate simulation of South East Europe (Crete) are presented. A full study in regards to the four climate regions of Europe is foreseen to provide values for development of a precise and integrated model of thermographic building simulations for evaluation of impact of climate change. Development of a third generation user interface software optimised portable metrology system (DHSPI II) is designed to record in custom intervals the surface of materials witnessing reactions under simulated climatic conditions both onfield and in laboratory. The climate conditions refer to real data-loggers readings representing characteristic historical building in selected climate zones. New generation impact sensors termed Glass Sensors and Free Water Sensors are employed in the monitoring procedure to cross-correlate climate data with deformation data. In this paper results from the combined methodology are additionally presented.

Saint Rocco Museum, a historical building in Venice, Italy is used as a case study to explore the performance of its’ lighting system and visible light impact on viewing the large size art works. The transition from threedimensional architectural rendering to the three-dimensional virtual luminance mapping and visualization within a virtual environment is described as an integrated optical method for its application toward preservation of the cultural heritage of the space. Lighting simulation programs represent color as RGB triplets in a devicedependent color space such as ITU-R BT709. Prerequisite for this is a 3D-model which can be created within this computer aided virtual environment. The onsite measured surface luminance, chromaticity and spectral data were used as input to an established real-time indirect illumination and a physically based algorithms to produce the best approximation for RGB to be used as an input to generate the image of the objects. Conversion of RGB to and from spectra has been a major undertaking in order to match the infinite number of spectra to create the same colors that were defined by RGB in the program. The ability to simulate light intensity, candle power and spectral power distributions provide opportunity to examine the impact of color inter-reflections on historical paintings. VR offers an effective technique to quantify the visible light impact on human visual performance under precisely controlled representation of light spectrum that could be experienced in 3D format in a virtual environment as well as historical visual archives. The system can easily be expanded to include other measurements and stimuli.

The present study is focused on two topics. The first one is a mathematical model, useful to understand the deformation of paintings, which uses straining devices, adjustable and micrometrically controlled via a pin supported in a hollow cylinder. Strains were analyzed by holographic interferometry (HI) technique using an appropriate frame. The second one concerns the need to improve the conservator’s knowledge about the defect’s detection and defect’s propagation in acrylic painting characterized of underdrawings and pentimenti. To fulfill this task, a sample was manufactured to clarify the several uncertainties inherent the influence of external factors on their conservation. Subsurface anomalies were also retrieved by near-infrared reflectography (NIRR) and transmittography (NIRT) techniques, using LED lamps and several narrow-band filters mounted on a CMOS camera, working at different wavelengths each other and in combination with UV imaging. In addition, a sponge glued on the rear side of the canvas was impregnated with a precise amount of water by means of a syringe to verify the “stretcher effect” by the digital speckle photography (DSP) technique (using MatPIV). The same effect also affects the sharp transition of the canvas at the stretcher’s edge. In this case, a possible mechanism is a direct mechanical contact between stretcher and canvas that was investigated by HI technique. Finally, advanced algorithms applied to the square heating thermography (SHT) data were very useful to detect three Mylar® inserts simulating different type of defects. These fabricated defects were also identified by optical techniques, while the visual inspection was the only one capable of detecting a biological damage.

Terahertz (THz) radiation is being developed as a tool for the analysis of cultural heritage, and due to recent advances in technology is now available commercially in systems which can be deployed for field analysis. The radiation is capable of penetrating up to one centimetre of wall plaster and is delivered in ultrafast pulses which are reflected from layers within this region. The technique is non-contact, non-invasive and non-destructive. While sub-surface radar is able to penetrate over a metre of wall plaster, producing details of internal structures, infrared and ultraviolet techniques produce information about the surface layers of wall plaster. THz radiation is able to provide information about the interim region of up to approximately one centimetre into the wall surface. Data from Chartres Cathedral, France, Riga Dome Cathedral, Latvia, and Chartreuse du Val de Bénédiction, France is presented each with different research questions. The presence of sub-surface paint layers was expected from documentary evidence, dating to the 13th Century, at Chartres Cathedral. In contrast, at the Riga Dome Cathedral surface painting had been obscured as recently as 1941 during the Russian occupation of Latvia using white lead-based paint. In the 13th Century, wall paintings at the Chapel of the Frescos, Chartreuse du Val de Benediction in Villeneuve les Avignon were constructed using sinopia under-painting on plaster covering uneven stonework.. This paper compares and contrasts the ability of THz radiation to provide information about sub-surface features in churches and Cathedrals across Europe by analysing depth based profiles gained from the reflected signal.

Here the exploitation of the laser induced plasma spectroscopy (LIPS) depth profiling in authentication studies of copper alloy and earthenware artifacts was investigated. Such an approach to the discrimination between original and counterfeit objects is based on the examination of the amplitude and shape of elemental distributions along ablation depths of several hundred microns. Thus, its application pass through preliminary assessments and correction of possible systematic errors of the measured profiles, which was the main aim of the present work. LIPS and ESEM-EDX measurements were carried out on two archaeological findings. We show that deep analytical probing produces not negligible intrinsic broadenings of the measured elemental Sn and Ca peaks and propose a correction based on the convolution integral. According to the latter, we demonstrate the actual depth profile can be calculated from the measured one through the experimental determination of the step response and the application of trial-and-error method.

Optical Coherence Tomography has been successfully applied to the imaging of painted objects in recent years. However, a significant limitation is the low penetration depth of OCT in paint because of the high opacity of paint due to either scattering or absorption. It has been shown that the optimum spectral window for OCT imaging of paint layers is around 2.2μm in wavelength. In this paper, we demonstrate a 1950nm OCT for imaging painted objects using a superfluorescent fiber source at low power.

We present multimodal nonlinear optical imaging of historical artifacts by combining Two-Photon Excited Fluorescence (2PEF) and Second Harmonic Generation (SHG) microscopies. Three-dimensional (3D) non-contact laser-scanning imaging with micrometer resolution is performed without any preparation of the objects under study. 2PEF signals are emitted by a wide range of fluorophores such as pigments and binder, which can be discriminated thanks to their different emission spectral bands by using suitable spectral filters in the detection channel. SHG signals are specific for dense non-centrosymmetric organizations such as the crystalline cellulose within the wood cell walls. We also show that plaster particles exhibit SHG signals. These particles are bassanite crystals with a non-centrosymmetric crystalline structure, while the other types of calcium sulphates exhibit a centrosymmetric crystalline structure with no SHG signal. In our study, we first characterize model single-layered samples: wood, gelatin-based films containing plaster or cochineal lake and sandarac film containing cochineal lake. We then study multilayered coating systems on wood and show that multimodal nonlinear microscopy successfully reveals the 3D distribution of all components within the stratified sample. We also show that the fine structure of the wood can be assessed, even through a thick multilayered varnish coating. Finally, in situ multimodal nonlinear imaging is demonstrated in a historical violin. SHG/2PEF imaging thus appears as an efficient non-destructive and contactless 3D imaging technique for in situ investigation of historical coatings and more generally for wood characterization and coating analysis at micrometer scale.

While OCT has been applied to the non-invasive examination of the stratigraphy of paint layers in recent years, it has been recognized that the resolutions of commercially available OCT cannot compete in depth resolution with conventional microscopic examination of cross-sections of paint samples. It is necessary to achieve resolutions better than 3 microns to resolve the thinnest layers of paint and varnish. In this paper, we demonstrate a Fourier domain ultrahigh resolution OCT at 810nm with depth resolution of 1.8 μm in air (or 1.2μm in varnish or paint).

Madonna dei Fusi (‘Madonna of the Yarnwider’) is a spectacular example of Italian Renaissance painting, attributed to Leonardo da Vinci. The aim of this study is to give an account of past restoration procedures. The evidence of a former retouching campaign will be presented with cross-sectional images obtained non-invasively with Optical Coherence Tomography (OCT). Specifically, the locations of overpaintings/retouchings with respect to the original paint layer and secondary varnishes will be given. Additionally, the evidence of a former transfer of the pictorial layer to the new canvas support by detecting the presence of its structure incised into paint layer will be shown.

"Cleaning" is a process of carefully identifying the cause of any deterioration or discolouration and then removing or treating these layers. The skill of the restorer is not only to understand the techniques and media used by the artist, but also to recognize what beauty lies beneath the veils of many years of neglect or adverse conditions. Surface cleaning is then one of the most important and sometimes controversial stages of the conservation process: it is an irreversible process that generally results in substantial physical changes of the object surface, raising thus a series of questions regarding aesthetics, the potential loss of historical information, and the ability to control the cleaning process adequately. Decisions have to be made regarding partial or complete removal of varnish: technical considerations include selection of a method that allows a great deal of control in the cleaning process, so that undesired layers can be removed without damaging the underlying ones by means of traditional cleaning methods, including mechanical or chemical removal. In this work we present a study of the optical properties of painting surfaces for the characterization of the cleaning process. Analyses were carried out by means of laser micro-profilometry and confocal microscopy. Measurements were carried out on a few paintings which are under repair at the Opificio delle Pietre Dure in Florence. Selected areas were surveyed with the two above mentioned techniques and results were correlated.

A novel hyperspectral imaging system (HI90, Bruker Optics), working in the mid-infrared range and recently developed for the remote identification and mapping of hazardous compounds, has here been optimized for investigating painting surfaces. The painting Sestante 10 (1982) by Alberto Burri has been spectrally and spatially investigated with the HI90 system revealing the distribution of inorganic materials constituting the artworks. In order to validate the results obtainable by the imager for the pigment identification previous tests on laboratory models were performed. Yellow, white and blue pigments painted with different binders (namely egg, alkyd, acrylic and vinyl) were investigated by the HI90. Afterwards, the polychrome painting Sestante 10 was investigated focusing the attention on the inorganic material distribution revealing the presence of different extenders (kaolin, BaSO₄, CaSO₄) mixed with the various silica-based pigments present in the painting. The brightness temperature spectra collected by HI90 have also been compared to single point reflection spectra acquired by a conventional portable FTIR spectrometer (Alpha-R by Bruker Optics) highlighting the good spectral quality of the imaging system. This comparison permitted also to evaluate the spectral response and the diagnostic strengths of the spectral range available by the HI90 imaging (1300-860 cm^-1), validating the reliability of the obtained chemical images. This study clearly highlights the high potential of the new hyperspectral imaging system and opens up new perspectives in the current scientific interest devoted to the application of mapping and imaging methods for the study of painting surfaces.

Thermal Quasi Reflectography (TQR), e.g. imaging in the thermal band 3-5 μm (MWIR), is discussed as innovative tool for the noninvasive analysis of pictorial surface layers in artworks, and its potential is demonstrated in some applications. The results encourage further developments in this field. The novel experimental technique, which has been recently introduced by the authors, is reviewed here giving focus to current research and potential applications.

We present the non-invasive study of historical and modern Zn- and Cd-based pigments with time-resolved fluorescence spectroscopy, fluorescence multispectral imaging and fluorescence lifetime imaging (FLIM). Zinc oxide and Zinc sulphide are semiconductors which have been used as white pigments in paintings, and the luminescence of these pigments from trapped states is strongly dependent on the presence of impurities and crystal defects. Cadmium sulphoselenide pigments vary in hue from yellow to deep red based on their composition, and are another class of semiconductor pigments which emit both in the visible and the near infrared. The Fluorescence lifetime of historical and modern pigments has been measured using both an Optical Multichannel Analyser (OMA) coupled with a Nd:YAG nslaser, and a streak camera coupled with a ps-laser for spectrally-resolved fluorescence lifetime measurements. For Znbased pigments we have also employed Fluorescence Lifetime Imaging (FLIM) for the measurement of luminescence. A case study of FLIM applied to the analysis of the painting by Vincent Van Gogh on paper – “Les Bretonnes et le pardon de Pont-Aven” (1888) is presented. Through the integration of complementary, portable and non-invasive spectroscopic techniques, new insights into the optical properties of Zn- and Cd-based pigments have been gained which will inform future analysis of late 19th] and early 20th C. paintings.

In recent years there have been enormous advances in nautical archaeology through developments in SONAR technologies as well as in manned and robotic submersible vehicles. The number of sunken vessel discoveries has escalated in many of the seas of the world in response to the widespread application of these and other new tools. Customarily, surviving artifacts within the debris field of a wreck are collected and then moved to laboratories, centers, or institutions for analyses and possible conservation. Frequently, the conservation phase involves chemical treatments to stabilize an artefact to standard temperature, pressure, and humidity instead of an undersea environment. Many of the artefacts encountered at an underwater site are now characterized and restored in-situ in accordance with modern trends in art conservation. Two examples of this trend are exemplified by the resting place of the wreck of the Titanic in the Atlantic and the Cancun Underwater Park in the Caribbean Sea. These two debris fields have been turned into museums for diving visitors. Several research groups have investigated the possibility of adapting the well-established analytical tool Laser Induced Breakdown Spectroscopy (LIBS) to in-situ elemental analyses of underwater cultural, historic, and archaeological artefacts where discovered, rather than as a phase of a salvage operation. As the underwater laser ablation associated with LIBS generates a “snowplough” shockwave within the aqueous matrix, the atomic emission spectrum is usually severely attenuated in escaping from the target. Consequently, probative experiments to date generally invoke a submerged air chamber or air jet to isolate water from the interaction zone as well as employ more complex double-pulse lasers. These measures impose severe logistical constraints on the examination of widely dispersed underwater artefacts. In order to overcome this constraint we report on water-immersion LIBS experiments performed with oblique laser irradiation and spectral detection at the complementary angle so as to view emission from behind the shockwave. Targets of silver, gold, and copper have been studied. It is found that this approach enables LIBS detection in water both in emission and in absorption. It appears that underwater inverse LIBS may be especially useful in underwater archaeology.

A couple of years ago we proposed, in this same session, an extension to the standard colorimetry (CIE '31) that we called Hypercolorimetry. It was based on an even sampling of the 300-1000nm wavelength range, with the definition of 7 hypercolor matching functions optimally shaped to minimize the methamerism. Since then we consolidated the approach through a large number of multispectral analysis and specialized the system to the non invasive diagnosis for paintings and frescos. In this paper we describe the whole process, from the multispectral image acquisition to the final 7 bands computation and we show the results on paintings from Masters of the colour. We describe and propose in this paper a systematic approach to the non invasive diagnosis that is able to change a subjective analysis into a repeatable measure indipendent from the specific lighting conditions and from the specific acquisition system. Along with the Hypercolorimetry and its consolidation in the field of non invasive diagnosis, we developed also a standard spectral reflectance database of pure pigments and pigments painted with different bindings. As we will see, this database could be compared to the reflectances of the painting to help the diagnostician in identifing the proper matter. We used a Nikon D800FR (Full Range) camera. This is a 36megapixel reflex camera modified under a Nikon/Profilocolore common project, to achieve a 300-1000nm range sensitivity. The large amount of data allowed us to perform very accurate pixels comparisions, based on their spectral reflectance. All the original pigments and their binding have been provided by the Opificio delle Pietre Dure, Firenze, Italy, while the analyzed masterpieces belong to the collection of the Pinacoteca Nazionale of Bologna, Italy.

In this paper, a fully automated 3D digitization system for documentation of paintings is presented. It consists of a specially designed frame system for secure fixing of painting, a custom designed, structured light-based, high-resolution measurement head with no IR and UV emission. This device is automatically positioned in two axes (parallel to the surface of digitized painting) with additional manual positioning in third, perpendicular axis. Manual change of observation angle is also possible around two axes to re-measure even partially shadowed areas. The whole system is built in a way which provides full protection of digitized object (moving elements cannot reach its vicinity) and is driven by computer-controlled, highly precise servomechanisms. It can be used for automatic (without any user attention) and fast measurement of the paintings with some limitation to their properties: maximum size of the picture is 2000mm x 2000mm (with deviation of flatness smaller than 20mm) Measurement head is automatically calibrated by the system and its possible working volume starts from 50mm x 50mm x 20mm (10000 points per square mm) and ends at 120mm x 80mm x 60mm (2500 points per square mm). The directional measurements obtained with this system are automatically initially aligned due to the measurement head’s position coordinates known from servomechanisms. After the whole painting is digitized, the measurements are fine-aligned with color-based ICP algorithm to remove any influence of possible inaccuracy of positioning devices. We present exemplary digitization results along with the discussion about the opportunities of analysis which appear for such high-resolution, 3D computer models of paintings.

Technical development and practical evaluation of a laboratory built, out-of-plane digital speckle pattern interferometer (DSPI) are reported. The instrument was used for non-invasive, non-contact detection and characterization of early-stage damage, like fracturing and layer separation, of painted objects of art. A fully automated algorithm was developed for recording and analysis of vibrating objects utilizing continuous-wave laser light. The algorithm uses direct, numerical fitting or Hilbert transformation for an independent, quantitative evaluation of the Bessel function at every point of the investigated surface. The procedure does not require phase modulation and thus can be implemented within any, even the simplest, DSPI apparatus. The proposed deformation analysis is fast and computationally inexpensive. Diagnosis of physical state of the surface of a panel painting attributed to Nicolaus Haberschrack (a late-mediaeval painter active in Krakow) from the collection of the National Museum in Krakow is presented as an example of an in situ application of the developed methodology. It has allowed the effectiveness of the deformation analysis to be evaluated for the surface of a real painting (heterogeneous colour and texture) in a conservation studio where vibration level was considerably higher than in the laboratory. It has been established that the methodology, which offers automatic analysis of the interferometric fringe patterns, has a considerable potential to facilitate and render more precise the condition surveys of works of art.

The SYDDARTA project is an on-going European Commission funded initiative under the 7th Framework Programme. Its main objective is the development of a pre-industrial prototype for diagnosing the deterioration of movable art assets. The device combines two different optical techniques for the acquisition of data. On one hand, hyperspectral imaging is implemented by means of electronically tunable filters. On the other, 3D scanning, using structured light projection and capturing is developed. These techniques are integrated in a single piece of equipment, allowing the recording of two optical information streams. Together with multi-sensor data merging and information processing, estimates of artwork deterioration and degradation can be made. In particular, the resulting system will implement two optical channels (3D scanning and short wave infrared (SWIR) hyperspectral imaging) featuring a structured light projector and electronically tunable spectral separators. The system will work in the VIS-NIR range (400-1000nm), and SWIR range (900-2500nm). It will be also portable and user-friendly. Among all possible art work under consideration, Baroque paintings on canvas and wooden panels were selected as the project case studies.

The paper presents examination methodology and results of identification tests and conservation treatments of amber specimens and prepared amber samples, selected from a large collection of the Museum of the Earth of Polish Academy of Sciences in Warsaw. Particular attention has been paid to the use of noninvasive methods of topographic and material analyses. Optimized conservation treatment has been applied to consolidate, store and exhibit a set of archaeological amber beads from the National Archaeological Museum in Warsaw.

The aim of these studies is to check the possibilities of implementing the Bookkeeper method in order to deacidify the watercolours and other works of art that are sensitive to water and other solvents. The Bookkeeper method as one of the methods of mass decidification has been known for 30 years. In this time, the influence of deacidification by means of this method on physical and chemical properties of papers was discovered. Hence, in our studies we focus on studying the influence of this process on the permanence of colours used in watercolours and other works of art. We would like to present the first phase of the studies. It was focused on conducting the aging tests of the model samples prepared with the use of selected watercolours, on two different types of paper. Deacidified and non-deacidified samples were submitted to the aging process by irradiating them by means of the Xenotest 150S device. In order to estimate the colour change, the colour measurements in the CIE L*a* b* colour space were used. The measurements were performed by the Elrepho SF450 spectrophotometer, manufactured by Datacolor (Switzerland). The outcome of this phase of the studies allows us to proceed to the second phase – the deacidification attempts of the original works of art.

The aim of this work is to study the surface modifications of poplar (Populus spp.) wood by reflectance spectrophotometry and Fourier Transform Infrared (FT-IR) spectroscopy in order to understand the mechanisms that cause the changes and to suggest possible solutions to avoid the degradation phenomena. Since colour changes on wood surfaces are due to photo degradation of its chemical constituents, the study of the relationship between CIELAB colour changes and changes in chemical composition due to irradiation is of practical importance both in cultural heritage and in contemporary artefacts and objects. Concerning the surface protection of wood, starting from the results obtained by testing different commercial products, the attention has been focused on Linfoil®, a novel organic preservative/consolidant product that seems to attract a great interest in the field of conservation of wooden artefacts. Linfoil® was chosen and analysed in order to understand its composition and its time stability using reflectance spectrophotometry, FT-IR spectroscopy and analytical pyrolysis coupled to a gas chromatographic-mass spectrometric system. Colour monitoring allowed to find that wood surface colour undergoes an important variation due to photo-irradiation, occurring within the first 24 hours and mainly due to L* decrease and b* increase. Though Linfoil® treatment modifies wood colour, nevertheless it seems to protect wood surface by reducing the yellowish. FT-IR spectroscopy allowed to investigate the rate of photo-degradation of wood surface due to lignin oxidation. The most important result is that a correlation of the colour changes may be derived with the photo-degradation of lignin obtained by FT-IR analysis.

In the world of Cultural Heritage the first concern is all about Conservation of the works of art. A piece of art in bad shape is meant to deteriorate to an irreversible stage. To avoid this, quite often it's needed to go through one or more cycles of restoration to clean and consolidate the various elements of the piece. The very second concern, once the work of art is restored and in good and stable shape, is its fruition. At the end of the day why one should do all that restoration work if nobody then can access and view? Yet viewing and enjoying an artwork means that a visitor would be able to see it at its best, and this means, almost always, to have a good lighting system. Today, both restoration and fruition can greatly benefit of all the available technologies, and achieve very high level quality. The goal of this paper is the development of an exposimetric system suitable to be extremely useful as a tool for the the non invasive analysis, as well as for the lighting design and lighting systems monitoring. Many diagnosis techniques that are used before the restoration stage, require a suitable lighting system to allow to extract from the painting the maximum amount of information through the acquisition of images in the range of visible as well as UV and IR light. A standard exposimeter is for its own nature, sensitive only to the visible light, constrained by the standard photometric sensitivity curve V(lambda). A wide band exposimeter would be, on the other hand, an invaluable tool to get higher precision and to speed up multispectral wide band images acquisition, avoiding time wasting fail and try cycles to record the subject under wide spectrum conditions. The same equipment can be used to monitor the quality of the light in a expo lighting system at, for example, a museum or a gallery. The light hitting a piece of art has to allow the visitor to see and appreciate all the color shades, and to appreciate the contrast of dark and bright areas due only to the painting (and not to a jeopardized light). At the same time the light has not to arm the surface and the pigments, with for example an excess of UV, that can influence the chemical bonds, or an excess of infrared that could rise the temperature to damaging levels.

In the framework of imaging, lighting systems have always played a key role due to the primary importance of both the uniformity of the illumination and the richness of the emitted spectra. Multispectral imaging, i.e. imaging systems working inside and outside the visible wavelength range, are even more demanding and require to pay further attention to a number of parameters characterizing the lighting system. A critical issue for lighting systems, even in the visible light, is the shape of the emitted spectra and (only in the visible range) the Color Rendering Index. The color we perceive from a surface is our eyes' interpretation of the linear spectral combination of the illuminant spectrum and the surface spectral reflectance. If there is a lack of energy in a portion of the visible spectrum, that portion will turn into black to our eyes (and to whatever instrument) regardless the actual reflectance of the surface. In other words a lack in the exciting energy hides part of the spectral reflectance of the observed subject. Furthermore, the wider is the investigated spectrum, the fewer are the sources of light able to cover such a range. In this paper we show how we solved both the problems of the not uniformity of the light beam, independently on the incident angle, and of the selection of a light source with energy rich and continuous enough emitted spectrum.

Portable 3D scanners with low measurement uncertainty are ideally suited for capturing the 3D shape of objects right in their natural environment. However, elaborate manual post processing was usually necessary to build a complete 3D model from several overlapping scans (multiple views), or expensive or complex additional hardware (like trackers etc.) was needed. On the contrary, the NavOScan project[1] aims at fully automatic multi-view 3D scan assembly through a Navigation Unit attached to the scanner. This light weight device combines an optical tracking system with an inertial measurement unit (IMU) for robust relative scanner position estimation. The IMU provides robustness against swift scanner movements during view changes, while the wide angle, high dynamic range (HDR) optical tracker focused on the measurement object and its background ensures accurate sensor position estimations. The underlying software framework, partly implemented in hardware (FPGA) for performance reasons, fusions both data streams in real time and estimates the navigation unit’s current pose. Using this pose to calculate the starting solution of the Iterative Closest Point registration approach allows for automatic registration of multiple 3D scans. After finishing the individual scans required to fully acquire the object in question, the operator is readily presented with its finalized complete 3D model! The paper presents an overview over the NavOScan architecture, highlights key aspects of the registration and navigation pipeline and shows several measurement examples obtained with the Navigation Unit attached to a hand held structured-light 3D scanner.

Grodziec collection of stained glass panels consists of fourteen objects depicting figures of saints. Probably they belong to one, uniform set from the one of Lower Silesia churches. Recently eight of them, already after conservatory treatment, are exhibited in Jagiellonian University Museum of Collegium Maius in Krakow, while remaining six, which will be restored in nearest future, are stored in the National Museum in Wroclaw. This paper presents the results of the investigation of composition and corrosion products of glass from three panels of Wroclaw group. Since comparative analysis of historic glass composition is vital for its dating, to obtain the possibly full set of composition data with particular stress on light elements identification, the multi technique approach was necessary. The physicochemical analysis was carried out by X-ray fluorescence (XRF), micro-Raman spectroscopy and scanning electron microscopy with energy dispersive X-ray spectrometer (SEM/EDX). The study revealed that some of stained glasses have composition characteristic of northern medieval glass (potash-lime-silicate) while other pieces could be dated on 16th or 19th century. This confirms the suggestion from the former historic and scientific investigation of Krakow's set that the Wroclaw panels may be of the same medieval origin as the Krakow's ones and that they were already restored, at least in 19th c. The possibility of working on the whole set of panels from the Grodziec collection opens up the opportunity for conducting exceptional scientific study which will lead to the definitive designation of the provenance of this important collection, its history and age.

In the present work a non-invasive technological study on three molds from Magnani’s mills in Pescia (Pistoia, Italy) was carried out. The three molds investigated have been those for making: 1) the invitation letters to the marriage between Napoleon and Maria Luisa of Austria in 1810; 2) the paper sheets used by Pablo Picasso in 1917 for the drawings of the Russian Ballets currently preserved in the Picasso Museum in Paris; 3) the holy manuscript Bhagavata Purana realized in India in 1840 and currently preserved in the “Museum of Art” of San Diego. The chemical composition of the metal alloy components were investigated and compared using Laser Induced Plasma Spectroscopy (LIPS), electron microscopy (ESEM-EDX) and Ion Beam Analysis (IBA) while shape and size comparisons were carried out by means of a homemade 3D digital microscopy device. Metallographic characterizations were also carried out on some very small samples. This allowed pointing out the different crafting features of the three molds. The results achieved and represent the first step towards an overall characterization, which will be carried out on Magnani’s mold collections.

Photonic technologies play a leading innovative role of research in the fields of Cultural Heritage (CH) conservation, preservation and digitisation. In particular photonic technologies have introduced a new indispensable era of research in the conservation of cultural artefacts expanding from decorative objects, paintings, sculptures, monuments to archaeological sites and including fields of application as diverse as materials characterisation to restoration practices and from defect topography to 3d artwork reconstruction. Thus the last two decades photonic technologies have emerged as unique answer or most competitive alternative into many long-term standing disputes in conservation and restoration of Cultural Heritage. Despite the impressive advances on the state-of-the-art ranging from custom-made system development to new methods and practises, photonic research and technological developments remain incoherently scattered and fragmented with a significant amount of duplication of work and misuse of resources. In this context, further progress should aim to capitalise on the so far achieved milestones in any of the diverse applications flourished in the field of CH. Embedding of experimental facilities and conclusions seems the only way to secure the progress beyond the existing state of the art and its false use. The solution to this embedment seems possible through the new computing environments. Cloud computing environment and remote laboratory access hold the missing research objective to bring the leading research together and integrate the achievements. The cloud environment would allow experts from museums, galleries, historical sites, art historians, conservators, scientists and technologists, conservation and technical laboratories and SMEs to interact their research, communicate their achievements and share data and resources. The main instrument of this integration is the creation of a common research platform termed here Virtual Laboratory allowing not only remote research, inspection and evaluation, but also providing the results to the members and the public with instant and simultaneous access to necessary information, knowledge and technologies. In this paper it is presented the concept and first results confirming the potential of implementing metrology techniques as remote digital laboratory facilities in artwork structural assessment. The method paves the way of the general objective to introduce remote photonic technologies in the sensitive field of Cultural Heritage.

Laser ablation was successfully used to sequentially remove layers of concretion and corrosion from the surface of a copper alloy spectacle plate from the shipwreck of His Majesty’s Sloop of War DeBraak. The H.M.S. DeBraak was a single-masted cutter that was originally a Dutch ship until it was taken by the British, refitted, and repurposed as a Royal Navy ship in 1796. The ship sank along the Delaware coast in 1798 and artifacts were recovered from the wreck site in 1984. This spectacle plate is an important part of the ships rudder and it is part of the collection of the Delaware Division of Historical and Cultural Affairs. The object was brought the Winterthur/University of Delaware Program in Art Conservation for treatment. The object was examined with cross section microscopy, Raman spectroscopy, X-ray fluorescence spectroscopy (XRF), and Energy Dispersive Spectroscopy (EDS) as well as Back Scattered Electron (BSE) analysis with a Scanning Electron Microscopy (SEM). Interestingly, layers of both copper and iron corrosion products were identified within the concretion. A 1064nm Long Q-Switch (LQS) laser with 100ns pulses was tested along with a Short Free Running (SFR) with 60 - 130 microseconds pulses, at various fluences and frequencies, to determine optimal cleaning parameters for removing the concretion. Laser cleaning also revealed fragments of wood from the original rudder, which were previously trapped within the concretion. After laser cleaning, the spectacle plate was treated with 3% Benzotriazole in ethanol and then given a protective microcrystalline wax coating.

Begin the abstract two lines below author names and addresses. The abstract summarizes key findings in the paper. It is a paragraph of 250 words or less. For the keywords, select up to 8 key terms for a search on your manuscript's subject. Precious artworks are in constant loan due to the increase demand for tour exhibitions around the globe. Archeological findings and historical parts of wallpaintings are detached and get into the route of a fraud market. Most of these detached art pieces are lost, destroyed or hidden by public view by anonymous collectors. The damage to the historical, cultural and aesthetic values is most of the times irreversible. Originality and authentication are essential properties in the identification of movable artworks provoking dispute and fraud actions endangering the long-lasting public approach to the precious but disputed works of art. Scientific community and technology developments are implemented in the battle against fraud and misinterpretation of origin through systematic and material classified studies. European projects have influenced and provoked intense research in this fragile field of modern technology applications and recent results are presented. Investigation protocols and classification needed for the standardization of valuation of these critical properties comprise an intense field of research embraced with international interest. In this paper it is presented long-lasting research effort with photonic technologies to bridge the results with the conventional means and the conservation expert opinion aiding to the identification and ensuring the origin of a masterpiece. Results from laboratory investigation and characteristic examples of paintings faced with the dispute of their authentication are given.

A rapid prototyping method is invented, which works on a specific data structure produced by an optical metrology technique: 360-degree surface profile scanning. A computer algorithm takes an object profile data, restructure the format, generate horizontal and vertical ribs, lay out the ribs on a 2D canvas and output the geometries to a file format compatible with laser cutters. A laser cutting machine is subsequently used to cut all the ribs from sheet materials. Then, the ribs are manually assembled based on computer-generated assembly codes. Through this process, the original object’s 3D surface can be prototyped rapidly at an arbitrary scale, which may well exceed the working dimension of the laser cutter.