Paper Feature Extraction from Digital Images

Digital archives are very useful to readers. However, they do not give enough information, such as paper, ink, and pigment, to satisfy researchers of materials and conservators of the documents. In this research, we describe paper feature extraction, such as laid and chain line pattern, watermark, syanome pattern, and itame pattern from digital images of paper

An assessment of multimodal imaging of subsurface text in mummy cartonnage using surrogate papyrus phantoms

Ancient Egyptian mummies were often covered with an outer casing, panels and masks made from cartonnage: a lightweight material made from linen, plaster, and recycled papyrus held together with adhesive. Egyptologists, papyrologists, and historians aim to recover and read extant text on the papyrus contained within cartonnage layers, but some methods, such as dissolving mummy casings, are destructive. The use of an advanced range of different imaging modalities was investigated to test the feasibility of non-destructive approaches applied to multi-layered papyrus found in ancient Egyptian mummy cartonnage. Eight different techniques were compared by imaging four synthetic phantoms designed to provide robust, well-understood, yet relevant sample standards using modern papyrus and replica inks. The techniques include optical (multispectral imaging with reflection and transillumination, and optical coherence tomography), X-ray (X-ray fluorescence imaging, X-ray fluorescence spectroscopy, X-ray micro computed tomography and phase contrast X-ray) and terahertz-based approaches. Optical imaging techniques were able to detect inks on all four phantoms, but were unable to significantly penetrate papyrus. X-ray-based techniques were sensitive to iron-based inks with excellent penetration but were not able to detect carbon-based inks. However, using terahertz imaging, it was possible to detect carbon-based inks with good penetration but with less sensitivity to iron-based inks. The phantoms allowed reliable and repeatable tests to be made at multiple sites on three continents. The tests demonstrated that each imaging modality needs to be optimised for this particular application: it is, in general, not sufficient to repurpose an existing device without modification. Furthermore, it is likely that no single imaging technique will to be able to robustly detect and enable the reading of text within ancient Egyptian mummy cartonnage. However, by carefully selecting, optimising and combining techniques, text contained within these fragile and rare artefacts may eventually be open to non-destructive imaging, identification, and interpretation

The portrait drawings of Hans Holbein the Younger: function and use explored through materials and techniques

This thesis examines the materials and techniques of sixteenth century artist Hans Holbein the Younger, with particular reference to his portrait drawings. The research reinstates the drawings as the primary source-material for investigation, thereby demonstrating the link between the materials and techniques chosen by Holbein, and the function or end-use of the drawings. Although around one hundred Holbein portrait drawings survive, the focus of this research is the eighteen that relate to currently attributed oil and miniature paintings. By focusing the research in this manner, it is possible to establish how Holbein constructed and used the drawings in the preparation of the finished oil painting. Furthermore, it explains how his choice and use of materials and techniques can help to establish the original context and function of the drawings. An important outcome of this research is a detailed description of the eighteen drawings that relate to a painted portrait. Having developed an effective method of examining and describing Holbein’s drawings, this research provides a thorough analysis of the materials and techniques used by him. This not only increases our understanding of his drawing processes, but also broadens the limitations of traditional connoisseurship by offering a more accessible tool, allowing objective visual analysis of an artist’s technique. This method of investigation can be applied to drawings in a wider context of sixteenth century artistic production. Moreover, it can also be used as a potential model for how to effectively ‘read’ a drawing in order to better understand its function and method of production. The results inform art historical and conservation research. A comprehensive, systematic visual examination of the drawings has helped to reveal new information on Holbein’s methods and materials, and offers insights into 16th century workshop practice. In many cases examination has clarified the sequence in which the media was laid down. Holbein’s emphasis on the contours that define sitters’ features has been much disputed, and their role, media, and application methods were unclear. What has previously been described as metalpoint marks were discovered by the author to be indentations, which have become filled with loose media, thereby giving the appearance of a drawn line. The indentations actually show evidence of tracing of the salient lines that capture likeness for transfer. The research has also revealed that red chalk was the preliminary media for defining features, and that Holbein developed standardised techniques for rendering flesh tones, making the drawing process more efficient. It is apparent that Holbein chose techniques to fulfill a particular role, and that there are clear links between these techniques and their location on a drawing

The Neapolitan Presentation Manuscripts of Tinctoris’s Music Theory: Valencia 835 and Bologna 2573

Despite the scholarly attention that has rightly been paid to Universitat de València, Biblioteca Històrica, MS 835, and Bologna, Biblioteca Universitaria, MS 2573, as crucially important textual sources for Tinctoris’s music theory, insufficient regard has so far been given to these two Neapolitan presentation manuscripts as historical artefacts that encode information about the priorities and concerns of those who brought them into existence. This thesis presents the first complete physical descriptions of these manuscripts, and employs detailed palaeographical, iconographical, and historical analysis to establish the likely circumstances of, and reasons for, their production. In the course of proposing identifications of the scribes and artists involved, analysing in fine detail their sequences of preparation, considering the organisational structure articulated by the decorated initials, interpreting the iconography of the portrait miniature on the frontispiece of Valencia 835, and marshalling complex heraldic evidence, many other Neapolitan manuscripts are brought into discussion. By analysing and contextualising Valencia 835 and Bologna 2573, therefore, the thesis functions also as a significant contribution to anglophone scholarship on the wider output of the Neapolitan scriptorium in the late fifteenth century. A newly enriched account is proposed of Tinctoris’s arrival and period of employment in Naples, and of his and the wider court’s involvement in the preparation of music theory manuscripts as instruments of political expression. This thesis, therefore, offers a re-appraisal of the genesis and later history of these two high-value music theory manuscripts. By presenting detailed codicological analysis and using it to construct and reshape historical narratives, it also provides a firm basis for future scholarly investigation into Tinctoris and music theory within the intellectual, cultural, and political climate of late fifteenth-century Italy

A 'philosophical storehouse': the life and afterlife of the Royal Society's repository

PhDIn June 1781, the Royal Society’s repository was transferred to the British Museum. Though ostensibly as a result of the limited space in the Royal Society’s purpose-built accommodation at Somerset House, the Society were perhaps also a little relieved to relinquish a collection that had proved to be somewhat burdensome during its residence at the Society and which was frequently criticised for its decaying specimens, broken items and missing, possibly stolen, objects. However this seems to be only part of the story. Drawing upon manuscript material in the Royal Society and the British Library, this study will examine the repository’s pattern of usage, collecting strategies and intellectual output throughout its life, in addition to exploring its afterlife at the British Museum using the British Museum’s, Royal College of Surgeon’s and Natural History Museum’s extensive archives. This thesis will seek to reveal an alternative account of the Royal Society’s repository arguing that it was comprised of a substantial and significant collection that the British Museum, at least initially, appears to have been grateful to receive and which, periodically, played a central role in the Society’s and naturalists' work