4DRL Report Series 8 - Scanning for restitution: Documenting the Allard Pierson’s Centuripe pyxis using cross-polarisation photogrammetry and RTI

For an assignment by Laurien de Gelder, curator of the archaeological collections at the Allard Pierson, a unique ceramic vase or pyxis (inv. APM13.988) with lid was documented using photogrammetry and RTI. The vessel originates from Centuripe, Sicily and was used in the 3rd century BCE as part as a burial gift inventory. These types of vases are well known for their rich and colourful paintings, applied after baking. For this reason, they have become desirable collectors’ items, mostly entering the market through grave robbing and illicit trade. Recently, the Allard Pierson received a request by a prosecutor from Italy to return the object. As part of the restitution agreement, the vase was fully documented using current digital documentation techniques in 2D and 3D. The purpose of the photogrammetric 3D model is to allow the Allard Pierson to exhibit a digital version of the object in various ways, while Reflectance Transformation Imaging (RTI) was employed for experimental analytical reasons. RTI allows for high resolution capture of surfaces that can be used for virtual relighting and various image enhancement techniques. We aimed to explore to what extent this technique could assist in documenting and visualising the application of paint layers, older restorations and damages to the surfaces. This report discusses the technical details and results of both documentation methods applied to the Centuripe pyxis.