3D Scans of Cuneiform Tablets

• Middle Eastern Cuneiform Tablets Collections: Target Collections and Imaging Strategies, Oxford, September, 6th, 2010

• Jörg Kantel, Max Planck Institute for the History of Science, Berlin

• Two-dimensional scans are often not enough to recognize signs or damages of the tablets
• There is a need for the possibility to work with lights
• Therefore there also is a need for the possibility to rotate the tablets
• Because we can ;)

• Resolution to low
• Smoothing the surfaces
• Texturing the surfaces

• Is a structured-light 3D scanner – not a laser scanner
• Stores the color information with the points of the scan
• Hight resolution (more than 5 megapixels) – therefore there is no need for smooting the surfaces

• Optical scanner on a stable tripod with a set of three objectives and sensors (for different resolutions)
• Control unit connects the scanner with the computer
• Massive turntable
• Dell computer with Windows XP (dongled with the Breuckmann software)

• The Breuckmann hardware is very robust and can be used outdoor
• Therefore it is devilevered in a stable flightcase
• It was used by an expedition if the Smithsonian Institute in Mongolia (scanning deer stones)
• It also was used by scanning capitals of monestary cloister in Italy (Kunsthistorisches Institut, Florence and ISTI - CNR, Pisa)

• … is »Fischertechnik«

• The scanner stores pictures (two per single scan)
• These pictures will be automatically (more or less) aligned
• Normally we need six single scans from every side of the tablet (automatically rotated on the turntable)
• Additionally two single scans from the front an the back of the tablet

• That means: 14 single scans are enough
• 14 single scans will be done in around 20 minutes
• But if there are gaps, holes or damages we need (often much) more single scans

• The pictures have to be loaded again
• They will be cleaned
• Afterwards the meshes will be calculated and the final 3D model will be generated
• Duration: Around 40 to 60 minutes per tablet (that's the reason why we bought one scan computer and three post production machines)

• The Breuckmann software can generate different output formats
• At the moment we prefer PLY (PoLYgon File Format), a free 3D format from the Standord University)
• But VRML or other formats are also possible
• Problem: Not every tool supports the color informations

• Breuckmann provides a macro for us that automatic generates the standard 6 side view (fat cross) of the CDLI
• Therefore there is no need to scan the tablets two dimensional again

• Breuckmann Viewer
• MeshLab

• Optoview is a free (free as in free beer) Viewer provided by Breuckmann
• It's a very fast viewer and it can set up to four different lights
• It's a small version of the scan software and therefore very comfortable to use for everybody of the scanning team
• But it runs only under Windows

• MeshLab (GPL) is a free (free as in free speech) and open source 3D viewer
• It's under active development by the ISTI-CNR in Pisa
• MeshLab runs under Windows, Linux und MacOS X (Intel only)
• MeshLab can set only one light (at the moment)
• MeshLab can import and export a lot of different 3D formats

• Let's look at some examples

• At the moment we are scanning the Hilprecht collection in Jena
• Until now we have scanned approx. 300 tablets (mostly mathematical and admnistration texts)
• We will provide a website, where you can download the 3D scans for free as well as the tools (Breuckmann Viewer, MeshLab)
• The website of the project: hilprecht.mpiwg-berlin.mpg.de

• Presenting the two-dimensional 6-side view on the web
• Simultaneously presenting a 3D-»thumbnail«
• Offering downloads as PLY and VRML files
• Providing metadaten separately as XML file

• How to handle broken or fragile tablets? How to join them?
• 3D thumbnail view (3D-PDF downsized a tablet to 3 MB - but without colors at the moment, downsized PLY – around 20 MB – with colors)

• 3D scanning of cuneiform tablets is possible
• We expect new opportunities of working and publishing the tablets
• At the moment the project is a pilote but the results are promising

From right to left: Peter Damerow (MPIWG, CDLI), Sarah Köhler (University of Jena, Hilprecht collection), Jörg Kantel (MPIWG) – not at the picture: Christina Tsouparopoulou (CDLI), Juliane Eule (University of Jena, Hilprecht collection)

• Questions?
• Thanks for listening
• URL: www.cognitiones.de/doku.php/3d_scans_of_cuneiform_tablets
• Back

Kategorie: Arbeitsmaterial Computergraphik → 3D → 3D-Scanner

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