Close-contact laser scanning digitally captures the X, Y and Z data of physical objects using a controlled laser beam. The scanner records the time of flight between the laser leaving the scanner, reflecting off a physical object, and then returning back to the scanner. Certain scanners can capture up to one million points of data per second, generating a large cloud of 3-dimensional (3D) points, known as point cloud data.
All laser scanners require a clear line-of-sight between the scanner and the environment or object which they intends to record. Multiple scans of the same feature are required from different viewpoints to create 3D models.
As part of our project, in order to record matzevot and evidence of cultural genocide in 3D, a FaroArm laser scanner was used alongside photogrammetry. This technique allowed us to create interactive models of complete matzevot and fragments.
Because of the accuracy of the scanner, we were able to:
- take many inscriptions that were difficult to read with the naked eye and make them visible in a digital environment
- understand the ways in which the matzevot had been damaged, thus enhancing our knowledge about the nature of cultural genocide.
- digitally reassemble matzevot fragments which were found in different parts of the cemetery).
Case Study: Piaski Cemeteries
In 2017, the “Recording Cultural Genocide and Killing Sites in Jewish Cemeteries” team sought to document and analyse the types of damage inflicted upon the cemeteries in Piaski (Poland) during the Holocaust and in its aftermath. A close-contact laser scanning arm was used to document and preserve surviving matzevot fragments. Some remained in situ. Others were discovered during the large-scale clearance work (see image below).
The post-processing of the laser scanning data provided the opportunity to examine any damage to matzevot and enhance the quality of inscriptions.
An interactive 3D model of a laser-scanned matzevah from Piaski new Jewish cemetery is shown below.