Recovering illegible writings in fire-damaged medieval manuscripts through data treatment of UV-fluorescence photography

New Frontiers in the Digital Restoration of Hidden Texts in Manuscripts: A Review of the Technical Approaches

“…UVF was applied by Pottier et al, 2019, on 132 medieval parchment manuscripts made illegible after a fire in the Chartres library in France [4]. The advantages of UVF are the low-cost equipment, including a standard digital camera and lens, the rapidness of image acquisition, and the uncomplicated image treatment.…”

2D macro-XRF to reveal redacted sections of French queen Marie-Antoinette secret correspondence with Swedish count Axel von Fersen

“…Mapping elemental composition [macro-x-ray fluorescence scanning (MA-XRF)] (3)(4)(5)(6), molecular signature [mid-infrared (IR) scanner] (7), multi/hyperspectral imaging (8)(9)(10), heat conduction (thermal imaging) (11), or far-IR absorption (THz imaging) (12), along with additional specific data processing (1,(13)(14)(15), can offer entirely new readings of a surface and reveal hidden or degraded contents. Up to this day, imaging research in historical manuscripts is mainly focused on discovering the inside text of rolled/folded papyri or parchments with x-ray tomography (16,17) or revealing the erased original content of palimpsests or faded/degraded documents using diverse imaging techniques (3,6,18,19). Few redacted historical documents such as MA and AF letters have been the subject of published work so far (for example, a musical score, the Luigi Cherubini's 1797 opera Médée, blacked out by his author with carbon ink) (20).…”