Micro-photogrammetry and traceology: new on-site documentation approaches using portable digital microscopes

This paper introduces a novel micro-photogrammetric application for the examination of technological traces using a portable digital microscope. The aim is to evaluate its potential, advantages, and level of detail within the context of traceology studies, highlighting its importance in particular for field documentation of unmovable items. The technique is non-invasive and applicable to samples that cannot be transported outside their regions/ countries of origin. Moreover, this methodological presentation aims to provide an extensive account of the utilized technology, the accessories, the possible uses and a series of experiments designed to replicate environmental and logistical conditions commonly encountered in the field. The goal is also to compare a 3D model obtained with a portable digital microscope to one obtained with a camera equipped with a macro lens, in order to highlight the level of detail achieved in trace visualization. The results are also expanded and discussed, including an examination of an archaeological case study. Additionally, to evaluate the validity and accuracy of the detected traces, the data obtained has been analyzed in the context of a qualitative assessment conducted using a stereomicroscope coupled with an optical fiber reflected light system.