The key aspects and features of the sculpture, 'The Thinker' by Auguste Rodin exhibited a... more The key aspects and features of the sculpture, 'The Thinker' by Auguste Rodin exhibited at the National Gallery of Victoria are discussed. Detailed examination of the sculpture has revealed that the sculpture's appearance for many decades was not as the artist had originally intended.
Such is its power and presence, this thylacine pelt causes an emotional response in the rational ... more Such is its power and presence, this thylacine pelt causes an emotional response in the rational professionals who have become its custodians - a once-living creature's beauty and completeness is such that the shock of its loss to the world is newly felt.
Q&A to conference paper titled: Corrosion, wear and corrosive wear; the story of lubrication syst... more Q&A to conference paper titled: Corrosion, wear and corrosive wear; the story of lubrication systems in large technology object storage and use
My name is David Hallam; I'm currently Senior Conservator Research and Technology at the Nati... more My name is David Hallam; I'm currently Senior Conservator Research and Technology at the National Museum. That means that I'm in charge of our research programs and I'm also in charge of our technological conservation program. Before that I was Head of Conservation at Queensland Museum, and before that I spent 20 odd years at the Australian War Memorial and I love functional objects. I also like Volvos.
Such is its power and presence, this thylacine pelt causes an emotional response in the rational ... more Such is its power and presence, this thylacine pelt causes an emotional response in the rational professionals who have become its custodians - a once-living creature's beauty and completeness is such that the shock of its loss to the world is newly felt.
The preservation and understanding of cultural heritage depends increasingly on in-depth chemical... more The preservation and understanding of cultural heritage depends increasingly on in-depth chemical studies. Rapid technological advances are forging connections between scientists and arts communities, enabling revolutionary new techniques for non-invasive technical study of culturally significant, highly prized artworks. We have applied a non-invasive, rapid, high definition X-ray fluorescence (XRF) elemental mapping technique to a French Impressionist painting using a synchrotron radiation source, and show how this technology can advance scholarly art interpretation and preservation. We have obtained detailed technical understanding of a painting which could not be resolved by conventional techniques. Here we show 31.6 megapixel scanning XRF derived elemental maps and report a novel image processing methodology utilising these maps to produce a false colour representation of a "hidden" portrait by Edgar Degas. This work provides a cohesive methodology for both imaging and...
Electrochemical impedance spectroscopy (EIS) is a well established technique for evaluating the c... more Electrochemical impedance spectroscopy (EIS) is a well established technique for evaluating the corrosion preventive properties of protective coatings. National Museum of Australia (NMA) staff have used this technique in the past to evaluate and rank the corrosion performance of a number of commercial waxy coatings in routine conservation use. This testing procedure is relatively simple and gives quantitative snapshot data about the performance of protective coatings, allowing them to be ranked objectively. The EIS test cell presently available is suitable for testing relatively hard, thick coatings. It cannot be used in the investigation of thin, delicate and easy-to-break films such as those formed by engine oil. The objective of this investigation was to fabricate an electrode suitable for testing thin oily films using conventional EIS test cells. We desired an EIS method that could be used for rapidly testing commercial engine oils and ranking their performance. Such a test prot...
A historical self-portrait painted by Sir Arthur Streeton (1867-1943) has been studied with fast-... more A historical self-portrait painted by Sir Arthur Streeton (1867-1943) has been studied with fast-scanning X-ray fluorescence microscopy using synchrotron radiation. One of the technique's unique strengths is the ability to reveal metal distributions in the pigments of underlying brushstrokes, thus providing information critical to the interpretation of a painting. We have applied the nondestructive technique with the event-mode Maia X-ray detector, which has the capability to record elemental maps at megapixels per hour with the full X-ray fluorescence spectrum collected per pixel. The painting poses a difficult challenge to conventional X-ray analysis, because it was completely obscured with heavy brushstrokes of highly X-ray absorptive lead white paint (2PbCO(3)·Pb(OH)(2)) by the artist, making it an excellent candidate for the application of the synchrotron-based technique. The 25 megapixel elemental maps were successfully observed through the lead white paint across the 200 × 300 mm(2) scan area. The sweeping brushstrokes of the lead white overpaint contributed significant detrimental structure to the elemental maps. A corrective procedure was devised to enhance the visualization of the elemental maps by using the elastic X-ray scatter as a proxy for the lead white overpaint. We foresee the technique applied to the most demanding of culturally significant artworks where conventional analytical methods are inadequate.
The preservation and understanding of cultural heritage depends increasingly on in-depth chemical... more The preservation and understanding of cultural heritage depends increasingly on in-depth chemical studies. Rapid technological advances are forging connections between scientists and arts communities, enabling revolutionary new techniques for non-invasive technical study of culturally significant, highly prized artworks. We have applied a non-invasive, rapid, high definition X-ray fluorescence (XRF) elemental mapping technique to a French Impressionist painting using a synchrotron radiation source, and show how this technology can advance scholarly art interpretation and preservation. We have obtained detailed technical understanding of a painting which could not be resolved by conventional techniques. Here we show 31.6 megapixel scanning XRF derived elemental maps and report a novel image processing methodology utilising these maps to produce a false colour representation of a " hidden " portrait by Edgar Degas. This work provides a cohesive methodology for both imaging and understanding the chemical composition of artworks, and enables scholarly understandings of cultural heritage, many of which have eluded conventional technologies. We anticipate that the outcome from this work will encourage the reassessment of some of the world's great art treasures. Preserving and interpreting the world's material cultural heritage requires increasingly sophisticated under-standings of chemical composition, environmental history, and deterioration mechanisms 1. Knowledge and understanding of historic materials has conventionally required the removal of samples which are subjected to analytical techniques, and the process frequently alters or destroys the specimen. Even sub-millimetre sampling " damage " to works of substantial cultural heritage can be unacceptable for highly valued objects. In art examination it is highly desirable that materials can be identified without sampling, and without change to the material being studied. Conventional analytical techniques have given inconclusive outcomes, in particular where the area of interest is obscured by an upper layer 2,3. Concealed paintings, early compositions that have been hidden by subsequent work, are important insights into artworks and artists. They can reveal the evolution of an artist's technique and can prove invaluable to the attribution of a work 4,5. Conventional X-radiography of paintings has been undertaken since 1896, and has been heavily relied upon in the understanding of paintings 6. X-ray absorption is mainly provided by the heavy metal components of pigments used, and the technique provides minimal quantitative or specific elemental identification information. The interpretation of X-radiography images is a highly subjective process. In recent years considerable effort has been expended into developing large-area non-invasive examination techniques of artworks and archaeometric study of objects to fulfil a growing need to accurately understand the elemental and molecular composition of artworks 7–16. This new analytical information has become critical in attribution and degradation studies and art historical assessments and is used to direct the practices of art conservators as they seek to implement new preservation strategies. It has been demonstrated with the X-ray fluorescence (XRF) technique that metallic elements from pigments in an underpainting can be detected and resolved with sufficient sensitivity to enable reconstruction of concealed paint layers 2,4,5,7,10,17. The first major synchrotron study, which revealed a woman's head under the Van Gogh painting Patch of Grass required extended examination time (~2 days, 2 second per pixel dwell time), and produced modest resolution 0.5 mm over an area of only 175 × 175 mm 2 2. This showed the power of scanning XRF, but also highlighted what had been the traditional limitation of slow pixel acquisition rates, which often resulted in compromises to the overall scan size and/or spatial resolution. In recent years the development of rapid scanning XRF methods 8,19,20 with millisecond analysis times have dramatically improved data collection
The key aspects and features of the sculpture, 'The Thinker' by Auguste Rodin exhibited a... more The key aspects and features of the sculpture, 'The Thinker' by Auguste Rodin exhibited at the National Gallery of Victoria are discussed. Detailed examination of the sculpture has revealed that the sculpture's appearance for many decades was not as the artist had originally intended.
Such is its power and presence, this thylacine pelt causes an emotional response in the rational ... more Such is its power and presence, this thylacine pelt causes an emotional response in the rational professionals who have become its custodians - a once-living creature's beauty and completeness is such that the shock of its loss to the world is newly felt.
Q&A to conference paper titled: Corrosion, wear and corrosive wear; the story of lubrication syst... more Q&A to conference paper titled: Corrosion, wear and corrosive wear; the story of lubrication systems in large technology object storage and use
My name is David Hallam; I'm currently Senior Conservator Research and Technology at the Nati... more My name is David Hallam; I'm currently Senior Conservator Research and Technology at the National Museum. That means that I'm in charge of our research programs and I'm also in charge of our technological conservation program. Before that I was Head of Conservation at Queensland Museum, and before that I spent 20 odd years at the Australian War Memorial and I love functional objects. I also like Volvos.
Such is its power and presence, this thylacine pelt causes an emotional response in the rational ... more Such is its power and presence, this thylacine pelt causes an emotional response in the rational professionals who have become its custodians - a once-living creature's beauty and completeness is such that the shock of its loss to the world is newly felt.
The preservation and understanding of cultural heritage depends increasingly on in-depth chemical... more The preservation and understanding of cultural heritage depends increasingly on in-depth chemical studies. Rapid technological advances are forging connections between scientists and arts communities, enabling revolutionary new techniques for non-invasive technical study of culturally significant, highly prized artworks. We have applied a non-invasive, rapid, high definition X-ray fluorescence (XRF) elemental mapping technique to a French Impressionist painting using a synchrotron radiation source, and show how this technology can advance scholarly art interpretation and preservation. We have obtained detailed technical understanding of a painting which could not be resolved by conventional techniques. Here we show 31.6 megapixel scanning XRF derived elemental maps and report a novel image processing methodology utilising these maps to produce a false colour representation of a "hidden" portrait by Edgar Degas. This work provides a cohesive methodology for both imaging and...
Electrochemical impedance spectroscopy (EIS) is a well established technique for evaluating the c... more Electrochemical impedance spectroscopy (EIS) is a well established technique for evaluating the corrosion preventive properties of protective coatings. National Museum of Australia (NMA) staff have used this technique in the past to evaluate and rank the corrosion performance of a number of commercial waxy coatings in routine conservation use. This testing procedure is relatively simple and gives quantitative snapshot data about the performance of protective coatings, allowing them to be ranked objectively. The EIS test cell presently available is suitable for testing relatively hard, thick coatings. It cannot be used in the investigation of thin, delicate and easy-to-break films such as those formed by engine oil. The objective of this investigation was to fabricate an electrode suitable for testing thin oily films using conventional EIS test cells. We desired an EIS method that could be used for rapidly testing commercial engine oils and ranking their performance. Such a test prot...
A historical self-portrait painted by Sir Arthur Streeton (1867-1943) has been studied with fast-... more A historical self-portrait painted by Sir Arthur Streeton (1867-1943) has been studied with fast-scanning X-ray fluorescence microscopy using synchrotron radiation. One of the technique's unique strengths is the ability to reveal metal distributions in the pigments of underlying brushstrokes, thus providing information critical to the interpretation of a painting. We have applied the nondestructive technique with the event-mode Maia X-ray detector, which has the capability to record elemental maps at megapixels per hour with the full X-ray fluorescence spectrum collected per pixel. The painting poses a difficult challenge to conventional X-ray analysis, because it was completely obscured with heavy brushstrokes of highly X-ray absorptive lead white paint (2PbCO(3)·Pb(OH)(2)) by the artist, making it an excellent candidate for the application of the synchrotron-based technique. The 25 megapixel elemental maps were successfully observed through the lead white paint across the 200 × 300 mm(2) scan area. The sweeping brushstrokes of the lead white overpaint contributed significant detrimental structure to the elemental maps. A corrective procedure was devised to enhance the visualization of the elemental maps by using the elastic X-ray scatter as a proxy for the lead white overpaint. We foresee the technique applied to the most demanding of culturally significant artworks where conventional analytical methods are inadequate.
The preservation and understanding of cultural heritage depends increasingly on in-depth chemical... more The preservation and understanding of cultural heritage depends increasingly on in-depth chemical studies. Rapid technological advances are forging connections between scientists and arts communities, enabling revolutionary new techniques for non-invasive technical study of culturally significant, highly prized artworks. We have applied a non-invasive, rapid, high definition X-ray fluorescence (XRF) elemental mapping technique to a French Impressionist painting using a synchrotron radiation source, and show how this technology can advance scholarly art interpretation and preservation. We have obtained detailed technical understanding of a painting which could not be resolved by conventional techniques. Here we show 31.6 megapixel scanning XRF derived elemental maps and report a novel image processing methodology utilising these maps to produce a false colour representation of a " hidden " portrait by Edgar Degas. This work provides a cohesive methodology for both imaging and understanding the chemical composition of artworks, and enables scholarly understandings of cultural heritage, many of which have eluded conventional technologies. We anticipate that the outcome from this work will encourage the reassessment of some of the world's great art treasures. Preserving and interpreting the world's material cultural heritage requires increasingly sophisticated under-standings of chemical composition, environmental history, and deterioration mechanisms 1. Knowledge and understanding of historic materials has conventionally required the removal of samples which are subjected to analytical techniques, and the process frequently alters or destroys the specimen. Even sub-millimetre sampling " damage " to works of substantial cultural heritage can be unacceptable for highly valued objects. In art examination it is highly desirable that materials can be identified without sampling, and without change to the material being studied. Conventional analytical techniques have given inconclusive outcomes, in particular where the area of interest is obscured by an upper layer 2,3. Concealed paintings, early compositions that have been hidden by subsequent work, are important insights into artworks and artists. They can reveal the evolution of an artist's technique and can prove invaluable to the attribution of a work 4,5. Conventional X-radiography of paintings has been undertaken since 1896, and has been heavily relied upon in the understanding of paintings 6. X-ray absorption is mainly provided by the heavy metal components of pigments used, and the technique provides minimal quantitative or specific elemental identification information. The interpretation of X-radiography images is a highly subjective process. In recent years considerable effort has been expended into developing large-area non-invasive examination techniques of artworks and archaeometric study of objects to fulfil a growing need to accurately understand the elemental and molecular composition of artworks 7–16. This new analytical information has become critical in attribution and degradation studies and art historical assessments and is used to direct the practices of art conservators as they seek to implement new preservation strategies. It has been demonstrated with the X-ray fluorescence (XRF) technique that metallic elements from pigments in an underpainting can be detected and resolved with sufficient sensitivity to enable reconstruction of concealed paint layers 2,4,5,7,10,17. The first major synchrotron study, which revealed a woman's head under the Van Gogh painting Patch of Grass required extended examination time (~2 days, 2 second per pixel dwell time), and produced modest resolution 0.5 mm over an area of only 175 × 175 mm 2 2. This showed the power of scanning XRF, but also highlighted what had been the traditional limitation of slow pixel acquisition rates, which often resulted in compromises to the overall scan size and/or spatial resolution. In recent years the development of rapid scanning XRF methods 8,19,20 with millisecond analysis times have dramatically improved data collection
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