Investigation of craquelure patterns in oil paintings using precise 3D morphological analysis for art authentication
The development of scientific technology for art authentication has elicited multidimensional evidence to distinguish forgeries from original artwork. Here, we analyzed the three-dimensional morphology of cracks that contain information, such as the painting features of artworks, using optical coherence tomography. The forgeries were produced by an expert from original oil paintings with cracks that occur owing to paint drying, canvas aging, and physical damage. Parameters, such as shape, width, and depth, were compared based on the cross-sectional images of the original and fake cracks. The original cracks were rectangular and inverted, but the fake cracks were relatively simple inverted triangles. The original cracks were as deep as the thickness of the upper layer and mostly were “thin/deep” or “wide/shallow”. The fake cracks were observed to be “’thin/shallow” or “wide/deep”. This study aims to improve the understanding of cr...
Munch and optical coherence tomography: unravelling historical and artist applied varnish layers in painting collections
Effective care of large-scale museum collections requires planning that includes the conservation treatment of specific groups of art works, such as appropriate cleaning strategies. Optical coherence tomography (OCT) has been successfully applied as a non-invasive method for the stratigraphic visualisation of the uppermost transparent and semi-transparent layers in paintings, such as varnishes. Several OCT case study examples have further demonstrated the capabilities of the non-contact interferometric technique to measure the thickness of the various varnish layers, to help monitor cleaning and associated optical changes, and to detect past restorations. OCT was applied for the detection of varnishes to 13 paintings by Edvard Munch (1863–1944) owned by the Norwegian National Museum of Art. The paintings have a controversial and complex varnish history and are displayed as a group according to their acquisition legacy. A prototype high-resolution portable SdOCT instrument was ...
Unveiling the Invisible in Uffizi Gallery’s Drawing 8P by Leonardo with Non-Invasive Optical Techniques
Until recently, the study of drawings by old masters has been confined to the art history conservation field. More specifically, scientific investigations of Leonardo’s drawings are still very few, possibly due to the latter’s extreme fragility and artistic value. However, analytical data are crucial to develop a solid knowledge base of the drawing materials and techniques used by artists in the past. In this work, we report on the application of non-invasive optical techniques on a double-sided drawing by Leonardo belonging to the Uffizi Gallery (8P). We used multispectral reflectography in the visible (Vis) and near-infrared (NIR) regions to obtain a spectral mapping of the drawing materials, to be subsequently integrated with technical information provided by art historians and conservators. Morphological analysis by microprofilometry allowed for the identification of the typical wave-like texture impressed in the paper during the sheet’s manufacture, as well as...
Non-invasive Survey of Rubens’ Ceiling Paintings at the Banqueting House Whitehall, London, by Means of Optical Coherence Tomography
This article presents the results of the examination by means of optical coherence tomography (OCT) of two of the nine monumental ceiling paintings by Peter Paul Rubens and his studio, still located in their original location at the Banqueting House, the only surviving building of the former Whitehall Palace in London. OCT is a non-invasive technique of structural imaging of layers semi-permeable to infrared light. The aim of the 2018 research campaign at the Banqueting House, conducted within the MOLAB programme under the IPERION CH project, was to determine the present condition of the paintings and thus inform decisions about future conservation planning for these unique paintings.
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OCT Captures Impressionistic Brushstrokes
Art conservators have enlisted a bevy of imaging techniques, including optical coherence tomography (OCT), to study valuable paintings and ensure their long-term preservation. Even though OCT can generate 3D images of scattering media with micrometer resolution and without destroying its subject, the method’s narrow field of view limits its ability to examine broad regions of an artist’s canvas. Researchers at two U.S. universities have built a hybrid scanning platform that couples OCT with a sampling algorithm to create 3D reconstructions of impressionist oil paintings (Appl. Opt., doi: 10.1364/AO.390326 ). Besides helping art historians to understand the creative techniques of artists and to repair damage to their paintings, the 3D reconstructions could be reproduced as tangible models to help people with visual impairments understand these works of art.
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Multi-scale optical coherence tomography imaging and visualization of Vermeer’s Girl with a Pearl Earring
We demonstrate multi-scale multi-parameter optical coherence tomography (OCT) imaging and visualization of Johannes Vermeer’s painting Girl with a Pearl Earring . Through automated acquisition, OCT image segmentation, and 3D volume stitching we realize OCT imaging at the scale of an entire painting. This makes it possible to image, with micrometer axial and lateral resolution, an entire painting over more than 5 orders of length scale. From the multi-scale OCT data we quantify multiple parameters in a fully automated way: the surface height, the scattering strength, and the combined glaze and varnish layer thickness. The multi-parameter OCT data of Girl with a Pearl Earring shows various features: Vermeer’s brushstrokes, surface craquelure, paint losses, and restorations. Through an interactive visualization of the Girl , based on the OCT data and the optical properties of historical reconstructions of Vermeer’s paint, we can virtually study the effect of the light...
Radio frequency based material estimation of old age 3D sculptures
The cultural heritage has its importance due to the information communicated by the heritage to the future generations. It is difficult to preserve cultural heritage over the centuries because of their volatile nature. In this paper, the preservation aids are considered for sculptures. The sculpture also includes the type of monument. The challenges are face deterioration during logistic and handling. Hence, it destroys the information carried by sculpture. In addition, the knowledge about materials used for construction of these sculptures help in maintenance of these sculpture. It helps in reconstructing the shape and color, which have been damaged earlier. The common techniques reported in the literature for broken structure and material estimation are optical coherence tomography (OCT), X-ray, THz scanning and Raman spectroscopy. These techniques used for retrieving material information are not portable and are costlier. Thus, the need is established in this paper for the device...
New Art Scanning Method Offers 3-D Image Of Painting’s Brush Strokes
As tempting as it may be, you can’t touch a painting in a museum. And now that many museums are closed, you’re even further from seeing the close-up detail in brush strokes that can tell you so much about how the art was created. But now, a collaboration between artists and researchers at Penn State and the New Jersey Institute of Technology have come closer to developing a method that makes it possible to scan a sizeable section of a painting and turn it into a 3-D model that maintains the fine brush stroke pattern details. This technology could help improve online art lessons and virtual museum tours as well as make paintings more accessible to visually impaired people.
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Spectral 3D reconstruction of impressionist oil paintings based on macroscopic OCT imaging
Art conservators have adopted optical technologies to improve conservation efforts; laser triangulation, stereophotogrammetry, structured light, laser scanners, and time of flight sensors have been deployed to capture the 3D information of sculptures and architectures. Optical coherence tomography (OCT) has introduced new imaging methods to study the surface features and subsurface structures of delicate cultural heritage objects. However, the field of view of OCT severely limits the scanning area. We present a hybrid scanning platform combined with an effective algorithm for real-time sampling and artifact removal to achieve macroscopic OCT (macro-OCT) imaging and spectral 3D reconstruction of impressionist style oil paintings.
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Laser-based technique captures 3-D images of impressionist-style brushstrokes
Researchers have developed a new strategy that uses optical coherence tomography (OCT) to acquire both the surface and underlying details of impressionist style oil paintings. This information can be used to create detailed 3-D reconstructions to enhance the viewing experience and offer a way for the visually impaired to experience paintings.
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Non-invasive survey of pre-restoration condition of the ceiling paintings by Peter Paul Rubens at the Banqueting House Whitehall, London, by means of Optical Coherence Tomography
This article presents the results of the examination by means of optical coherence tomography (OCT) of two of the nine monumental ceiling paintings by Peter Paul Rubens and his studio, still located in their original location at the Banqueting House, the only surviving building of the former Whitehall Palace in London. OCT is a non-invasive technique of structural imaging of layers semi-permeable to the infra-red radiation. The aim of the 2018 research campaign at the Banqueting House, conducted within the MOLAB programme under the IPERION CH project, was to determine the present condition of the paintings and thus inform decisions about future conservation planning for these unique paintings.
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Hidden for centuries, Rembrandt’s secrets are finally being revealed
Rembrandt van Rijn’s The Night Watch is one of the world’s best-known paintings. Dating from 1642, the strikingly large canvas – 4.6m across and 3.8m high – depicts a group of civic militia guards led by Captain Frans Banninck Cocq, the central figure with a red sash and lacy collar (the man to his left, resplendent in cream doublet and feathered hat, is his lieutenant, Willem van Ruytenburch). The scene, which contains 31 figures in total, is unusually chaotic. Rather than solemnly lining up his subjects for a portrait, as was customary at the time, Rembrandt captures them in full, messy action. Guardsmen brandish muskets, pikes and swords; a dog barks at a drummer mid-beat; a young girl peers through the crowd, a chicken hanging from her waistband. Some details glint in Rembrandt’s trademark dramatic lighting while others are cast in shadow, forcing your eyes to dance around the image, picking out new features with each glance. For more than 200 years...
Spectral-Domain Optical Coherence Tomography for the Non-Invasive Investigation of the Pigment Layers of Tang Dynasty Tomb Murals Exhibited in Museums
Optical coherence tomography (OCT) is a non-invasive subsurface three-dimensional imaging technique based on the Michelson interferometer. Due to the nature of non-invasive detection and high-speed acquisition, OCT is efficient for imaging intact objects to generate a complete overview of their microstructure. This paper presents the investigation of the pigment layer and ground layer of three Tang dynasty tomb murals exhibited in museums with Spectral-domain optical coherence tomography (SD-OCT). The investigation results demonstrated that SD-OCT system can obtain clear images of the subsurface microstructure and preservation status of ancient murals and can precisely locate and measure the location of the mural defect, by means of en-face image, the system can distinguish the draft line covered by pigment layer. The SD-OCT is an attractive alternative for cultural heritage research and high-resolution OCT images can provide valuable information for Chinese cultural heritage resear...
Laser cleaning of paintings: in situ optimization of operative parameters through non-invasive assessment by optical coherence tomography (OCT), reflection FT-IR spectroscopy and laser induced fluorescence spectroscopy (LIF)
Nowadays the use of laser technology as a highly precise tool for the cleaning of paintings is gaining ground. The development of a non-invasive analytical protocol aimed at thorough assessment of the treated surfaces and real time monitoring of the laser cleaning action is thus becoming imperative. This ensures that no side effects (e.g. discoloration, darkening, blackening) will occur on the painting surfaces due to laser ablation. In the present study the potential of the combined use of optical coherence tomography (OCT) and reflection FT-IR spectroscopy for in situ non-invasive assessment of laser cleaning procedures has been investigated on a historical easel painting donated to science. Specifically, OCT and FT-IR analyses were carried out before and after each cleaning test in order to carefully assess the condition of the painting surfaces upon their irradiation with a KrF excimer laser and evaluate the removal of weathered and/or non-original materials (i.e. waxes, aged na...