by Stamatopoulos, M. I. and Anagnostopoulos, C. N.
ABSTRACT
Photogrammetry has emerged as a valuable technique for digitizing real-world objects. In the field of archae-ology, the generation of realistic 3D models from 2D images has become a preferred method for scholars en-gaged in excavation, conservation, and restoration work. While the concept of modelling entire excavations or small objects from various angles is exciting, the precision and realism of 3D models remain areas of inves-tigation. Initially, photogrammetric techniques were primarily used for large-scale or medium-scale objects. However, in recent years, there has been a growing interest in applying photogrammetry to model small-scale objects. The crucial question for small objects, ranging from a few centimeters to a few tens of centimeters in size, is whether photogrammetry can produce high-precision 3D models. This paper focuses on a small ce-ramic sherd from a handmade replica of a large red-figure amphora. Through an iterative process involving photogrammetry and macrophotography (close-up photography), ten different digital models of the sherd are generated. From each of these models, thickness measurements are extracted at 24 specific points, allowing for a comparison and calculation of uncertainties associated with these measurements. The dispersion of the measurements around the mean value provides an estimation of the actual size values and measurement er-rors, enabling an evaluation of the precision of photogrammetry in size recognition. Furthermore, the same sherd is measured ten times using a caliper at the same points, and the thickness measurements are compared to calculate the uncertainties of the caliper measurements. By estimating the sizes and their respective errors, the measurement error of the photogrammetry technique can be determined. Overall, this study aims to in-vestigate the precision of photogrammetry in generating high-precision 3D models and compare it to the measurements obtained from a caliper.
