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Switzerland 2005: Expedition to the Alps
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Cultural Heritage Imaging adapts Reflection Transformation Imaging (RTI) technology to document artifacts spanning millennia of human history from 3 awesome archaeological collections in Switzerland |
| Relevant Fields: |
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Archaeology, anthropology, art history, museum studies and management, preservation projects, private and civic collections, libraries, galleries, and archives. |
| Research Issue: |
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Creating 3-dimensional (3D), archival quality images for diverse artifact collections. The objects occur in a variety of shapes and sizes. The artifacts have many different surface qualities -- ranging from highly reflective metal coins to items with worn or partially obscured inscriptions. Many of the items are extremely valuable, light-sensitive or fragile and cannot be handled very often. The Swiss archivists who manage the collections have very precise documentation requirements. Imaging data must be reliable, consistent, reproducible, and based on exacting standards. |
| Results: |
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114 objects from 3 collections photographed and documented in 14 days. Data captured for 186 luminous 3D Reflection Transformation Imaging (RTI) files and 7 object movies. More than 40 gigabytes (GB) of raw data archived for further processing and analysis. |
| Benefits: |
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The high-resolution 3D image files are versatile enough to be used for many purposes, such as documentation, archiving, presentation on the Web, in print, in museum or gallery displays, kiosks, and interpretive programs. Non-technical staff can learn the techniques, even those who have little imaging experience. The images produced can be shared with the public over the Internet. |
A Cultural Crossroads Through the Ages
Despite its rugged alpine terrain, Switzerland has always been home to many travelers and adventurers. Ancient settlements occupy virtually every valley that shelters a pass through the jagged Alps. For millennia, these villages and towns have seen all manner of adventurers, pilgrims, and conquerors pass through or stay for a while. Many of these trekkers left behind wonderful archaeological legacies in the form of secret coin hoards, stashes of beautiful ceramics, and other precious works of art.
Journey of discovery.
CHI researchers set off on their alpine expedition in Fall 2005 when they spent 14 days documenting 114 objects from 3 Swiss collections. CHI staff created spectacular 3D images of gleaming Greek, Celtic, and Roman coins, Celtic funerary ceramic animals, and bronze sculptures and jewelry.
| For this project, CHI developed an automatic RTI capture dome. This system uses a digital SLR camera and fiber optic light source. The single fiber optic illuminator allows for precise filtering of the light allowing imaging of fragile light sensitive objects like ancient lead and wax document seals without damage. CHI volunteers Tim Lindholm and Michael Hyde deserve special recognition for their efforts in developing the RTI capture dome – a sleek device that travels well. CHI also captured the world's first multi-view RTI data set. |
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Lead papal seal from the Collection of the Grand St. Bernard |
Museum of Money
What better place than Switzerland to have a Musée Monétaire? Housed in an elegant Rumine Palace in Lausanne in the Swiss Canton of Vaud, the money museum has a numismatic collection of more than 100,000 coins made of gold, silver, and other metals. A large percentage of the coins came from the historic treasury of Savoy along with local hoards lost or buried by travelers from many eras. CHI spent several days in this stalwart repository documenting ancient coins selected by the Director, Dr. Anne Geiser.
Among the fascinating coin images captured with CHI techniques are a series of Celtic coins (circa 300 BCE). The Celtic versions of widely circulated Macedonian originals portray Philip II of Macedon, father of Alexander the Great, using elegant, stylized, abstract compositions.
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Celtic gold coin depicting Phillip II of Macedon from the Musée Monétaire
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Palais de Rumine housing the Musée Monétaire de Lausanne (cabinet des médailles) |
All Roads Lead to Valais
The Canton of Valais has everything – fine wines, fabulous cheese and chocolate, and even the Matterhorn, one of Switzerland’s highest peaks. Valais also has a world-class archaeological collection partially housed in Martigny and renowned for its excellent Celtic, Roman, and Medieval artifacts from many excavations. The intrepid CHI explorers made images of bronze sculptures, incised ceramics, and a silver coin hoard. While they were capturing these images, they were also capturing valuable process history data. |
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Bronze sculpture of the Roman Goddess Tutela |
Keeping track of data.
A big advantage of CHI techniques is that they preserve all of the data and digital information collected during the imaging process. When they developed their methods, CHI researchers incorporated the actions feature in Adobe Photoshop software to record all image processing steps and the settings used for each image. Other files generated during the process retain light position settings, command line settings, and file conversion settings. These data, files, and settings are important pieces of the process because other scholars can use this information to replicate what CHI has done. The ability to reproduce CHI’s results contributes to the scientific validity of the process.
“Coins present a special documentation challenge. Even with direct visual examination, some details are hard to discern. CHI methods provide complete surface information.”
— Mark Mudge, President, Cultural Heritage Imaging |
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Sharing an Ancient Collection with the World
The final stop for the CHI expedition of Fall 2005 was the stellar collection maintained by the Congregation of the Grand St. Bernard. Perched in a perfect alpine valley and surrounded by sharp-edged mountain summits, the monastery was founded in the 11th century CE. The famed St. Bernard rescue dogs originated in this area. Over the centuries, many wayfarers passed through the valley and found shelter at the monastery and other structures. The collection grew through the years as antiquities, coins, documents, and seals were carefully saved for posterity. The monks excavated many sites in the region and preserved artifacts in their collection. The congregation also maintains a Hospice at the Simplon Pass, which is 2,000 feet lower than the Grand St. Bernard. Given the late time of year, the CHI team stayed and worked with the collection in the Simplon Hospice with archivist Jean-Pierre Voutaz. |
Simplon Hospiz,
Simplon Pass, Switzerland
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“I [explain] to groups of young people ... that they are part of a long chain of human beings [who have] crossed the Alps [over the] millennia.”
— Jean-Pierre Voutaz, Congregation Archivist, Congregation of the Grand St. Bernard |
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“ My favorite object was a gorgeous, 1700 BCE Bronze Age neck piece. Thirty-seven hundred years in the ground gives bronze a color you can achieve no other way. No one has ever shot a combination object movie with Reflection Transformation Images (RTIs) and this was the perfect piece to shoot that way.”
— Carla Schroer, Director, Cultural Heritage Imaging |
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Inspired to experiment.
CHI staff captured images of lead papal seals and Celtic ceramic jars shaped like a lion, rabbit, and bird. CHI researchers also used the fiber-optic dome device to capture image data for a very special item – a Bronze Age torque (neck piece) from 1700 BCE. The monks found this object with a skeleton at a grave site. The CHI imaging techniques revealed a delicate geometric pattern incised on the torque. The uniqueness of the neck piece inspired CHI to capture the first multi-view RTI. The Torque was placed on a turntable and RTIs were captured every 30 degrees of rotation. In 2006, a new multi-view RTI viewer was built by Tom Malzbender at HP Labs, that enables the torque to be turned to an area of interest and then viewed using reflection transformation. This process is described in the paper.
| GEAR LIST |
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SLR digital camera |
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Laptop computer with remote camera control software and Adobe Photoshop |
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Tripods |
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Automatic object movie capture structure based on a programmable Seitz Phototechnik panorama stage with detachable vertical adjustment module (optional) |
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Portable aluminum-frame lighting dome with fiber optic lighting array and mesh screen carrying case (optional) |
| TECHNOLOGIES DEPLOYED |
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All of these technologies are available FREE in the public domain. See For More Information for Web sites. |
| Polynomial Texture Mapping (PTM): |
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Image-based representation of the appearance of a surface under varying lighting directions. |
| PTM Object Movies (POM): |
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A synthesis of individual PTMs into an integrated, multi-viewpoint, interactive presentation that can be viewed on a computer and over the Web with free viewer software. |
| POM Viewer: |
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Movie viewer software that assembles PTM images into an interactive movie that can be viewed over the Web or downloaded and viewed on a computer. |
| Reflection Transformation Imaging (RTI): |
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Mathematical techniques to transform image reflection data to accommodate changing light directions and to enhance surface details. Developed for use with PTMs by Tom Malzbender and his colleagues at HP Labs. |
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Removing dust from a coin plate in Valais
CHI team in Lausanne
Wax document seal depicting Edward I. From the collection of the Congregation of the Grand St. Bernard.
Mark with tray of coins in Lausanne
Valais bovine resident
Celtic ceramic female head from the collection of the Congregation of the Grand St. Bernard.
Symbol of the Simplon Hospice
Marlin cleaning a coin in the dome
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