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UCLDH research activity June 2021

By Lucy Stagg, on 30 June 2021

The UCLDH team have been busy as ever, despite continuing COVID-19 restrictions. Here’s just a few examples of recent activity:

Adam Crymble has published a monograph, Technology & the Historian: Transformations in the Digital Age (University of Illinois press, 2021) and a co-authored piece with Maria José Afanador-Llach (‘The Globally Unequal Promise of Digital Tools for History: UK and Colombia Case Study’ in Adele Nye (ed.) Teaching History for the Contemporary World (Springer, 2021), 85-98.).

Oliver Duke-Williams has been doing a lot of engagement work around the 2021 Census, including a radio interview with talkRadio. Read his co-authored blog on the The ebb and flow of UK census data

Julianne Nyhan has had various publications including  Named-entity recognition for early modern textual documents: a review of capabilities and challenges with strategies for the future. (Journal of Documentation, 2021. Co-authored with Marco Humbel, Andreas Vlachidis, Kim Sloan and Alexandra Ortolja-Baird)

Patrick White  has been co-leading a workshop series called Working With Code in collaboration with Research IT services, for Slade students making work in different coding environments such as Godot (game engine), Arduino (micro-controllers), Sonic Pi (live music production based on Ruby), and P5 (JavaScript version of Processing environment).

Tim Williams has been working on the Central Asian Archaeological Landscapes project. Their geospatial database, managed in QGIS, currently comprises 52,408 sites. Of these, 17,123 were known sites, gathered through the digitisation of archival material by our partners in Central Asia, while 35,285 have been digitised from a range of satellite imagery. They are exploring approaches to automatic change detection and Google Earth algorithms for automatic site detection. They are also using historic imagery (CORONA, Google Earth, etc.), DEMs, and scanned and geo-rectified Soviet maps, to create historical map layers, to examine landscape change, destruction, damage and potential threats to archaeological heritage. There is currently over 8TB of clean archival data on UCL Research Data storage, comprising 137,173 files scanned in 6,749 folders. Each folder is a document (notebook, passport folder, envelope with films, etc). This data is linked with the public facing Arches platform and UCL Open Data Repository. As a test, they have very recently placed 6 sets of geospatial data on UCL Research Data Repository (17.45GB) and those have already been viewed 2,540 times, with 1,973 items downloaded. From the repository there are also links to other digital material – for example 3D models on Sketchfab.

Stock Illustrations, Free to Reuse

By Rudolf Ammann, on 2 February 2021

Composition with glitch capture, mojibake and moresque eements

Composition with glitch capture, mojibake and moresque pattern elements

In spring last year the UCLDH co-founder Melissa Terras invited me to join her and Gavin Inglis on an unusual project. For whatever comedy might be had from the undertaking, the project  trained artificial neural networks on several years’ worth of historical Edinburgh Fringe festival programmes to generate new virtual show listings. My brief at first consisted in developing the brand identity and building the website, but, having familiarised myself with the project, I suggested that the purely textual show listings should also be accompanied by illustrations, which I’d be happy to create and supply. The suggestion was accepted. So, at the start of the Festival in August, the project went live under the name ImprovBot.ai, and it kept churning out a dozen illustrated AI-generated show listings a day for three weeks on end.

The images are now available for creative re-use as non-restrictively licenced stock illustrations. Here’s some very brief discussion and a few pointers to the various ways of getting hold of the images.

Producing digital illustrations by the hundreds requires a certain serial approach to their manufacturing, so it helps to have archives on hand that can be drawn on for visual elements to tweak and recombine. I have documented the main elements in the ImprovBot.ai series elsewhere. In this post, let me just highlight some of the threads that tie this illustration series to previous work I’ve done for Melissa and UCLDH.

As a designer and a visual artist I have been collaborating with Melissa for more than a decade. Prior to ImprovBot.ai (see Melissa’s account of her recent adventures in AI, incidentally), we’ve worked together on a variety of projects, including her book The Professor in Children’s Literature, which I typeset and whose book cover I designed. This cover, along with a few other references to other prior art that I’ve manage to sneak in, is among the elements I’ve used repeatedly as part of the series’ ‘extras‘:

Book cover remix: Professor Branestawm and Lehrer Lämpel

Book cover remix: Professor Branestawm and Lehrer Lämpel (drawings by W. Heath Robinson and Wilhelm Busch, respectively)

The extras, as their name suggests, are perhaps not very central to the ImprovBot.ai series. By contrast, glitch captures are a frequently used element. Typically consisting of arbitrarily coloured  pixel strings, they appear in many image compositions in the series. The pixels are sampled from image files and screen renderings that have gone haywire for some reason, provoked or unprovoked. They are drawn from the same stock of materials I’ve previously used around UCLDH to complement and expand upon the Centre’s pixel-looking logo. Here’s a plain example of  the barely processed source material:

Glitch capture, enlarged from a screenshot taken of a real-life rendering issue provoked by low random-access memory (RAM)

Glitch capture, enlarged from a screenshot taken of an unintended rendering issue provoked by low random-access memory (RAM)

Some of the illustrations are more complex in their make-up, featuring other elements thrown into the mix, such as moresque patterns and mojibake:

Composition with glitch captures

A more complex composition with several elements conjoined

Availability

The whole set of Improvbot.ai illustrations is available for reuse and can be picked up individually from the project website and the Twitter feed. The images , briefly reviewed by category on a separate page, can also be browsed by these categories. The categories most suitable for re-use are probably these:

Moresque | Capture | Dataviz | Base64 | Network | Hardmod | Mojibake | Noise | Extras

Also available, but perhaps less suitable for reuse might be these categories:

Identity: ImprovBot | Identity: Improverts | The Bot, incl. Multiples Edinburgh and Multiples Shakespeare |

A zip archive of the full illustration set is available for downloading from Zenodo.org, and a subset of individual illustrations is distributed via Pixabay.com.

Licensing and Reuse

The illustrations are distributed under the CC-BY-NC licence, the image set on Pixabay under even less restrictive terms.

Some of the images might be suitable for book cover art, a blog post illustration, or they might inspire you to simply play with them and produce a few remixes of your own. We’re looking forward to seeing them show up in unexpected places!

Facilitating digital art for UCL Raw Materials: Plastics, using 3D modelling and photogrammetry

By Lucy Stagg, on 9 September 2019

UCLDH Deputy Director, Prof Tim Weyrich, has been providing technological support to facilitate an artist residency programme, part of the UCL Raw Materials: Plastics Knowledge Exchange project led by PI Katherine Curran, funded through UCL Innovation & Enterprise. The project is a collaboration with Bow Arts Trust in east London, the Institute of Making, the Slade School of Fine Art and the UCL Department of Art History.

The artist in residence, Frances Scott, uses digital and analogue film processes to create her artworks. This summer, her work has been part of an exhibition at Bow Arts and an extensive programme of community projects in East London around Raw Materials: Plastics.

Furthermore, Frances’ film PHX [X is for Xylonite] has been selected to be screened at the 57th New York Film Festival on 6th October 2019.

Frances Scott explores the history and usage of plastic in this imaginative essay film. Using three-dimensional animations, distorted vocal recordings, and the words of Roland Barthes, she connects the founding of the first plastics factory in 1866 and the development of cellulose nitrate, a key element in the creation of film stock.

The film includes animated 3D models of objects from UCL Institute for Sustainable Heritage’s Historic Plastic Reference Collection, made using photogrammetry and laser scanning techniques, and hand-processed 16mm film footage of data collected from ISH laboratory equipment.

Recent publications on imaging techniques from UCLDH team member Dr Kathryn Piquette

By Lucy Stagg, on 4 February 2019

UCLDH team member Dr Kathryn Piquette has had several works published recently, including:

Dr. Kathryn Piquette undertaking Reflectance Transformation Imaging (RTI)

Dr. Kathryn Piquette undertaking Reflectance Transformation Imaging (RTI)

Multimodal imaging of papyrus article in Heritage Science journal

By Lucy Stagg, on 23 March 2018

The team behind the UCLDH Research Project Deep Imaging Egyptian Mummy Cases is pleased to have an article published in the Springer Heritage Science Journal 2018 6:7.

The article is ‘An assessment of multimodal imaging of subsurface text in mummy cartonnage using surrogate papyrus phantoms’ and the abstract reads as follows:

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.

You can download and read the full article on Springer Open.

UCL Advanced Imaging Consultants (UCLAiC) undertake imaging projects on a range of heritage materials

By tcrnkep, on 12 January 2018

Chiddingstone Castle ancient Egyptian coffin lid, probably 25th Dynasty.

Chiddingstone Castle ancient Egyptian coffin lid, probably 25th Dynasty.

It’s been about a year and a half since UCLDH announced the establishment of UCL Advanced Imaging Consultants (UCLAiC, with a core team of Melissa Terras, Adam Gibson and myself) and began offering Reflectance Transformation Imaging and Spectral Imaging services from the UCL Multi-Modal Digitisation Suite research facility based in central London. We have since been undertaking imaging projects on a range of fascinating heritage materials. From Roman lead tablets and Egyptian mummy portraits to Persian and Mediaeval manuscripts and modern works of art, the advanced techniques we use are helping to reveal hidden writing, underdrawings and other marks that are difficult to see with the naked eye.

As we wrap up work from 2017, we are pleased to report on one of the highlights from the past years’ projects, namely multispectral imaging on a 2500-year old Egyptian coffin lid held in the collections of Chiddingstone Castle in Kent, England.

This wooden lid, shaped to represent the human form, is covered with a thin layer of yellow gesso and the head and chest are embellished with red, blue and yellow paint. A column of hieroglyphic text runs down the centre of the lid, from the brightly coloured broad collar down to the feet. Intended to ensure the sustenance of the deceased in the afterlife, this offering formula is formed of hieroglyphic signs painted in black outline with a blue-green infill. The glyphs on the foot area, however, have become very faded and damaged over time yet this is the very location where the name of the owner of the coffin would have been written.

Lower part of the coffin lid showing preserved hieroglyphic text and largely ‘invisible’ name on foot panel.

Lower part of the coffin lid showing preserved hieroglyphic text and largely ‘invisible’ name on foot panel.

Keen to learn if the name could be recovered, Chiddingstone Castle commissioned me to conduct multispectral imaging on the damaged foot area. Our multispectral system (supplied by R. B. Toth Associates), uses a medium-format, 60-megapixel PhaseOne IQ260 Achromatic camera to take a series of high-quality digital images. Illumination is provided by low heat, narrowband light emitting diodes (LED) at 12 different wavelengths from ultraviolet to near infrared, with the application of a 6-position motorised filter wheel (developed and integrated by Dr Bill Christens-Barry of Equipoise Imaging). Together with the assistance of SEAHA PhD student, Cerys Jones, the multispectral system was transported from the UCL Multi-Modal Digitisation Suite to the Castle in order to conduct the imaging onsite.

Cerys Jones and Kathryn Piquette calibrate the UCL multispectral system.

Cerys Jones and Kathryn Piquette calibrate the UCL multispectral system.

We applied 12 different wavelengths from ultraviolet to near infrared. Initial results were achieved using infrared (IR) illumination. These wavelengths, which are longer than visible light, are absorbed by carbon-based inks/paints and thus provided increased contrast between the outlines of the hieroglyphs and the surrounding surface. Thanks to the flexibility of our MSI system and Cerys’ familiarity with the specific optical properties of the pigment Egyptian blue, we tested further combinations of wavelengths and filtering. Visible induced infrared luminescence (VIL) proved vital for visualising the faint traces of paint surviving in the interior of the hieroglyphs, and we were thrilled to successfully recover the shapes of the majority of the hieroglyphs spelling out the deceased’s name.

Cerys Jones and Kathryn Piquette examine the multispectral imaging results.

Cerys Jones and Kathryn Piquette examine the multispectral imaging results.

With this image data in hand, I was able to research the name and, with the assistance of other Egyptologists, determine that the hieroglyphs most likely spell out “Irethoreru”. This name was relatively common  among males during the 1st millennium BCE and can be translated as “The Eye of Horus is against them”. The name was presumably intended to protect its bearer against his enemies, although without specifying whether these enemies were material or otherworldly. UCLAiC are pleased to have contributed to the re-discovery of the name of this ancient Egyptian who lived over 2000 years ago. This exciting work also recently appeared as part of a BBC report on UCL’s research on non-destructive technical imaging for recovering ancient hidden writing (see also: UCL News) and is also reported on the SEAHA blog.

Detail of foot panel under visible light (left), infrared (IR) illumination (middle) and visible induced infrared luminescence (VIL, right).

Detail of foot panel under visible light (left), infrared (IR) illumination (middle) and visible induced infrared luminescence (VIL, right).

While the mystery of the name has been solved, there is yet much to learn about the Chiddingstone Castle coffin lid. It was acquired by Denys Eyre Bower in the mid-20th century but unfortunately its original provenance is not known. The lid is probably part of an outer coffin that held an inner coffin which, in turn, held Irethoreru’s mummified body. One wonders whether elements of his burial equipment made their way into other UK/European museums and collections. Indeed, many Egyptian artefacts from the Third Intermediate Period and beyond (c.1000–c.300 BCE) bear the name “Irethoreru” (which may also be rendered as “Iret-hor-irou”, “Iret-horru”, “Iret-[en]-Hor-eru” or “Iretenhoreru”). Further detailed research, advanced imaging and materials analysis will be necessary to discover whether any of these funerary objects relate to Chiddingstone Castle’s Irethoreru. If you think you might have further information that could help Chiddingstone Castle learn more about their coffin lid please contact: curator@chiddingstonecastle.org.uk.

For further information about the imaging services and training courses offered by UCLDH Advanced Imaging Consultants, please visit the page or contact advancedimaging@ucl.ac.uk!

Optical coherence tomography of the first printed edition of Euclid

By Lucy Stagg, on 2 January 2018

Adam Gibson, Professor of Medical Physics and a member of the UCLDH team, has been working with Tabitha Tuckett in UCL Special Collections to see if they can find any interesting features associated with the printed diagrams in the margins of the first printed edition of Euclid’s Elements. The printer, a man called Erhardt Ratdolt, had to work out a method for printing diagrams.

Adam has written a blog post, about his findings, where you can read more about:

how modern imaging methods might be able to cast light on Ratdolt’s 500 year old printing innovation.

Optical coherence tomography of the first page of Euclid’s Elements

Optical coherence tomography of the first page of Euclid’s Elements

Imaging the first printed edition of Euclid’s Elements

Papers aplenty

By Lucy Stagg, on 28 April 2017

We’re very busy here at UCLDH, delivering papers and promoting our wonderfully diverse portfolio of research

Martin Zaltz Austwick, our Associate Director and Senior Lecturer in Advanced Spatial Analysis and Visualization, has been reporting on the Survey of London: Whitechapel project at the annual meeting of the American Association of Geographers in Boston, at a seminar for Geospatial Innovations in the Digital Humanities in Lancaster, and at a workshop on Visualizations and other digital possibilities at Birkbeck, London.

Duncan Hay, Research Associate at the Centre for Advanced Spatial Analysis, spoke at an event for World Poetry Day, organised by the Digital Scholarship team at the British Library.

Andreas Vlachidis and Antonis Bikakis will be presenting their paper on “Semantic Representation and Enrichment of Cultural Heritage Information for Fostering Reinterpretation and Reflection on the European History” at the ITN-DCH Final Conference on Digital Heritage, on 23-25 May 2017.

Pete Williams will be giving a paper at the IJAS International Conference for Academic Disciplines in Venice, on 20- 23 June 2017.

New Reflectance Transformation Imaging (RTI) training course

By Lucy Stagg, on 29 November 2016

We are rolling out our new Reflectance Transformation Imaging (RTI) training course!

Courses will take place at UCL in our Multi-Modal Digital Imaging Suite. Each course, led by Dr. Kathryn Piquette, includes a combination of lectures, demonstration, and practical hands-on sessions:

  • Learn how to apply highlight Reflectance Transformation Imaging (RTI)
  • Gain experience in applying RTI to portable objects and larger fixed surfaces of various material types
  • Become proficient in capture, processing and manipulation of RTI datasets for diverse applications
  • Gain familiarity with related computational photography and processing techniques for augmenting and re-using RTI data
  • Apply what you learn in small teams of 2-3 people for hands-on work

There is more information available, including pricing and how to register.

UCLDH Advanced Imaging Consultants

By Melissa M Terras, on 21 July 2016

UCL Centre for Digital Humanities are pleased to announce that we now have capacity to offer Reflectance Transformation Imaging and Spectral Imaging services from our Multi-Modal Digitisation Suite research facility based in central London.

Reflectance Transformation Imaging (RTI), also known as Polynomial Texture Mapping (PTM), is a high-resolution, non-invasive and non-destructive imaging technique for documenting fine surface details. Unlike conventional photographs, images created using the RTI capture method can be virtually relit. The direction of the light source can be moved around in real time to give 3D appearance to surface shapes for systematic inspection of fine surface details.

Spectral Imaging is a high-resolution, non-invasive and non-destructive form of computational photography that can disclose features of the object that are invisible to the naked eye in natural light, and can enhance faded writings, reveal palimpsest and under-drawings, as well as aiding in pigments, binders and other materials identification. Spectral imaging helps clarify and support research, scholarly and other goals. The UCL state-of-the-technology spectral imaging system can be applied to documents and manuscripts, polychrome artworks, and a range of archaeological and heritage objects.

The kinds of material we can handle and are suitable for specialist imaging include:
• Documents, manuscripts, maps
• Artworks and other painted objects
• Coins, medals, jewellery
• Other objects bearing fine details such as seals and impressed sealings, cuneiform tablets, as well as inscriptions, carvings, bas-reliefs
• Forensic evidence or any object/surface requiring detailed examination.

For further information, please see our UCLDH Advanced Imaging Consultants page or contact advancedimaging@ucl.ac.uk.