Methods & Technology

The methods utilized for digital preservation were photogrammetry and 3D printing. To begin, a high-resolution camera was used to take 150 still frame shots of the object where the angle of the camera changed by a few degrees with every shot by rotating the object. The photos were then uploaded into a photo editing application where the background of every photo was manually edited out. 

Once finished, the images were uploaded to Sketchfab where the software aligned the photos and built the 3-D image of model. A preview of this was built first that possessed a less dense point cloud in under 10 minutes. If all the points were aligned correctly in the preview, which occured for this model, then the software built the dense point cloud over several hours with all of the points necessary to create the 3-D image. Although the points aligned well for this model in the preview, if they had not, the points would have needed to be manually aligned to their correct locations. After the dense point cloud was built, the mesh which ties all the points together was constructed and the number of faces the object is comprised of was able to be viewed. For example, the wireframe image and image displaying the vertex normals can be viewed below where 749.1k triangles and 374.6k vertices are displayed in the photos respectively. Finally, the texture was then developed in the model. This feature takes the color from the original photos and adds them to the faces of the object. Generally, the more faces the object possesses, the more accurate the model is to the original form.

Following the creation of the 3D model, the Sketchfab model was uploaded to another software program that the 3D printer could read. From this the 3-D print was created at 3/4ths scale. Considering that all the software was free, besides the costs of the computer, camera, and 3-D printer, the model quality and ease of building was impressive. To improve, a higher resolution camera or even a laser scanner if available might have produced a more accurate model; but, considering this object is not well known, it would be mismanagement of the university's resources when considering the cost-benefit analysis of price and the impact of higher quality replicas. Besides, both the 3-D model and print are more than sufficeint with the resources and technology on hand.