Facilities - Virtual Faunal Comparative Collection
Comparative animal skeletons are not always available to zooarchaeologists for use in identifying archaeological faunal remains. In order to fill this gap, we are building a virtual comparative skeletal collection using the Breuckmann triTOS-HE structured light scanner. The high resolution 3D images can be transported on a laptop computer for use in fieldwork or laboratory. Although such images will never replace genuine comparative skeletons for identifying fossils, the images suffice for basic identifications in remote field locations.
Software: This project employs the OptoCAT© software provided by the manufacturer of the scanner. With this software, objects are scanned and the data are converted into 3D meshes. For example, an object must be scanned in a series of small rotations (18º x 20), followed by the alignment and merging of all data into one, comprehensive mesh. We completed the first two years of this project using OptoCAT 2004 but are now using the much-improved 2007 version. When using normal 3D mesh formats, it is possible to export and import the scans for use in other programs. OptoCAT 2007 formats are: STL, PLY, WRL and DXF.
Light tent: cube-shaped tent, 120 cm walls, constructed from a lightweight, permeable fabric through which the light is dispersed evenly. Scanned objects retain better texture, color and have fewer shadows using the light tent, i.e., significantly less time for processing the scans.
Light source: three photographic halogen lamps (26 W)
Rotation table: 20 cm diameter, covered with black cloth. The rotation table moves by means of communication with the software. A scan normally consist of 20 rotations, each of 18°, resulting in a full 360° scan of an object.
Scanning animal bones involves several steps. In general, larger bones with detailed topography require more time to scan and process (3-5 hours). Smaller bones with smooth surfaces and minimal topography can be scanned and processed more quickly (~2 hours).
Figure 1: Scanner on tripod in preparation for scanning a horse skull on the rotation table.
Figure 2: The setup for using the scanner: the technician controls the scanner, lamps and rotation table from the computer.
Figure 3: View of scanning setup from above, illustrating the benefitsof using a photographic light tent to evenly distribute light for optimal scanning with minimal shadows.
Scanning animal bones involves several steps. In general, largerbones with detailed topography require more time to scan and process (3-5 hours). Smaller bones with smooth surfaces and minimal topography can be scanned and processed more quickly (~2 hours).
Niven, L., Steele, T.E., Finke, H., Gernat, T., Hublin, J.-J. (2009)
“Virtual skeletons: using a structured light scanner to create a 3D
faunal comparative collection.“ Journal of Archaeological Science 36:
Examples of scans from a modern horse, gazelle, barbary sheep, ibex, and
reindeer (one juvenile, one adult) can be found here: http://www.eva.mpg.de/evolution/files/downloads.htm
For more information on the virtual fauna project, please contact:
- Teresa Steele:
- testeele [at] ucdavis.edu
- Hannes Finke:
- hannesfinke [at] gmx.de
- Uta Schwarz:
- uta.schwarz [at] eva.mpg.de