Technical
Latest technology for high-quality, rapid, digital documentation of ceramic fragments
Check out the details in this Journal of Field Archaeology article
Data acquisition
- Two laser modules (A, E) project visible lines onto the specimen from both sides. The scratch-resistant glass table ensures clear imaging even from the bottom.
- Using the sheet-of-light triangulation principle, the two profile cameras (D, F) capture digital images of the respective laser lines to generate a complete section of the potsherd in real time.
- The 5-megapixel photo camera (B) complements the drawing with a standard picture. The illumination is provided by either the integrated high-power LED (C) or by an external light source.
Standard workflow
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The sherd to be scanned is manually positioned over the glass work surface by the operator or with the aid of the integrated helping hands. During the positioning, the profile is continuously evaluated and displayed live on the computer screen
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In the first step, the operator takes the characteristic vertical cross section of the sherd
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After that, the profile orientation is set either manually or, if the vessel rim is preserved, by aligning the rim with the glass surface
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The horizontal profile is taken to determine the radius of the vessel at an arbitrary point
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Any additional details, such as handles or plastic elements, are acquired and aligned with the drawing
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The drawing is enhanced with inflection lines, break lines, annotations, and a color photograph of the sample
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The finished output is stored in a database for further processing or publishing
Data storage
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Graph-based database Deposit stores finished drawings along the original acquired “raw” data and additional metadata
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Final drawings in SVG format with export options to PDF and PNG
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All data also available as polygons for custom analytic pipelines, e.g., shape matching or morphometrics
Photographic documentation
The LAP includes a 5-megapixel camera for detailed photography of archaeological artifacts. Focus and depth of field are adjustable, allowing both close-up imaging and quick adaptation to larger objects.
For applications requiring finer detail, the optional High-Resolution Photo addon upgrades the system to a 20-megapixel imager. It includes two manually interchangeable high-resolution lenses: one for general documentation and another providing 3× higher magnification, covering one ninth of the original image area for detailed close-ups.
RTI surface visualization
The optional RTI Resolver addon captures the artifact under several directional lights and combines the images into an interactive dataset. Users can change the virtual lighting direction after capture and apply enhancement modes to reveal subtle surface details such as decorations, tool marks, wear, fingerprints, and shallow inscriptions.
The capture takes only a few seconds, and the resulting RTI data can be stored together with the object drawing and photographs. The addon uses the LAP’s photo camera and can be combined with the High-Resolution Photo addon for finer detail.
