To restore the original flexibility of the parchment, the leaves must be humidified gently. Following a protocol developed by the conservation department at the Bibliothèque nationale de France, two procedures may be used:
- leaves may be placed in a humidifying chamber for several hours
- or each leaf may be placed between two layers of sympatex, sandwiched between two blotting papers.
Once re-hydrated, the leaves are cleansed of impurities, the folds and wrinkles are eased out, and the flattened leaves are affixed with clips on cardboard forms, made to measure. Once relaxed and “re-stretched”, the leaves can be manipulated; the easing of folds and wrinkles reveals zones of text that were otherwise unreadable.
Each manuscript is digitalized twice in high-resolution colour, before and after relaxation, according the norms furnished by the photographic service at IRHT and under its supervision.
In 2012-2013, the Bibliothèque nationale de France made a documentary film about the conservation of the manuscripts of Chartres at the Technical Centre at Bussy-Saint-Georges: La renaissance des manuscrits médiévaux de Chartres.