Recovering Palimpsest Manuscripts: Methods, Best Practices, and Lessons from Two Decades of Experience

Palimpsest manuscripts, found on the shelves of ancient and modern libraries, are made of reused materials: they are usually parchment leaves from which the writing was removed and later substituted by a new text. Scholars have been aware of their existence and have attempted to study them—particularly since the early 18th century—often using methods now regarded as destructive, such as treatments with chemical reagents. In recent years, digital non-invasive breakthroughs such as Multispectral Imaging, Hyperspectral Imaging, and X-ray Fluorescence have revolutionized the study of these handwritten objects. Projects like the Archimedes Palimpsest and the Sinai Palimpsests Project have transformed how scholars and scientists investigate palimpsest manuscripts, thanks to the use of digital multispectral imaging and advanced image processing techniques. This paper aims to review how, over the past twenty years, the Early Manuscripts Electronic Library (EMEL) and MegaVision—coordinating more than twenty projects and over a hundred contributors, from scholars to programmers—have significantly advanced the field of non-invasive palimpsest research, innovating and standardizing methods to uncover, among others, hidden and previously unknown Byzantine texts.