From the perspective of paleontological science, it is important that the original fossils of ‘Barbara’ are made available in perpetuity for further academic study. It goes without saying, that once the original fossilized bones are inlayed into a fully mounted specimen for museum exhibit, these fossils are hard for paleontologists to access again. An important development from a scientific perspective is that high resolution 3D digital models have developed to such an accurate degree that they can now replace real bones for a wide variety of research scenarios.
‘Barbara’s’ photogrammetric scans were a top priority for the team of scientists working on this specimen, and full scans of every bone were created after preparation and before the specimen was mounted for exhibit.
The most suitable scanning methodology for objects of complex shape and variable size is photogrammetry, a “Structure From Motion” scanning method based on digital photography. The scans capture the external shape as well as the color of the fossil in extremely high detail.
Photogrammetry models are created by taking high resolution digital images of an object, with either the camera, the object or both moving between shots. Overlapping photos from different angles allows the Agisoft Metashape software to calculate the relative position of camera and object for each image. A simple tie point cloud is created, which gives the base for a high density point cloud. This point cloud is meshed to produce a solid polygon model. A high resolution 2D texture is then calculated by using selected images of the object.
During the first photoset, a scale bar with two or more fix points at a known distance is added. Using a scale bar with two fix points at a distance of 10 cm for ‘Barbara’ allows the software to calculate and scale each bone to its original size.
‘Barbara’ is an incredibly important specimen from a paleontological science perspective. Due to the high resolution of each fossilized bone’s texture, which shows important surface details, as well as the exact resizing of each bone, the Photogrammetry process using Agisoft Metashape provides an excellent approach to enable the continued study of ‘Barbara’ by academics in perpetuity.