Holographic mapping at the Paris Museum of the Middle Ages

The museum crew installing the capital into the holographic device

Faire parler les pierres

Make the stones talk. This is the title of the exhibition at the Musée de Cluny - musée national du Moyen-Âge in Paris, running from November 19, 2024, to March 16, 2025, highlighting the medieval sculptures of Notre-Dame.

Following the fire on April 15, 2019, and the reconstruction work that began immediately after, the Notre-Dame de Paris Cathedral underwent an unprecedented and in-depth study during the three years leading up to its reopening.

This exhibition is part of a series of exhibitions and conferences leading up to the monument's reopening in December 2024. We had already contributed to this initiative at Sorbonne University Abu Dhabi through a previous project based on the same research with the public institution responsible for the conservation and restoration of Notre-Dame de Paris.

This time, in collaboration with the museum, the Institut de Recherches Historiques du Septentrion de Lille (IRHiS) at the University of Lille, and the PLEMO 3D platform within the André Chastel Center at the Faculty of Letters, Sorbonne University, Holusion continued its work on the holographic mapping of a Notre-Dame capital.

In partnership with Inrap, the Cluny Museum presents an exceptional exhibition centered on medieval sculptural decorations from Notre-Dame Cathedral. Alongside remarkable polychrome fragments from the 13th-century choir screen, the exhibition features an Iris46 holographic display showcasing, for the first time, a new perspective on a forgotten capital fragment that had been overlooked for 40 years.

Digital Solutions in the Service of Research

This capital was discovered in 1982 during renovation work in the nave of Notre-Dame de Paris Cathedral. This medieval capital, with its highly damaged decorations, was unearthed by workers and categorized as "Out of Context" before being placed in the reserves of the Cluny Museum.

However, in 2019, the scaffolding erected for the cathedral's restoration allowed researchers to closely observe its decorations. As a result, a connection was made between a capital featuring winged creatures and the capital fragment discovered 40 years earlier.

Digitized for the occasion using photogrammetry and lasergrammetry techniques by the PLEMO 3D platform, the two sculpted pieces were analyzed through a comparative study using digital overlay via the Blender software.

Through this process, their striking similarities became evident: the same size, the same design, and the same masonry. This comparison raises a significant question: why did two such similar capitals follow such different paths?

Highlighting research works

Credits of the installation displayed on the holographic display

Previously forgotten, the capital fragment, once considered Unidentified, has finally been brought out of storage to be revealed to the public under the spotlight of the exhibition.

Placed behind a holographic display, a presentation film is shown to not only describe the hypotheses surrounding the history of this capital but also to highlight the similarities between the two sculpted stone decorations using the Pepper's Ghost technique.

Like its counterpart sent to Abu Dhabi, this capital has been given a new lease on life to imagine its original state. However, unlike its counterpart, its reconstruction was not recreated but directly derived from its supposed twin, which is still installed today on one of the small columns of the ambulatory.

By merging real archeological discoveries and digital imagery, holographic innovation provides a modern, non-invasive, and non-destructive solution that semantically enriches the artwork while preserving its integrity.

Acknowledgments and Credits

Mixed-reality installation comparing two capitals from Notre-Dame, one unearthed during cathedral renovations in 1982 and preserved at the Cluny Museum, the other still in place in the ambulatory.

A holographic display utilizing the Pepper's Ghost optical illusion brings their respective digitizations together.

Image synthesis by Thibault Guillaumont and Jeanne Rossat (Holusion), design and execution by Sébastien Dumetz (Holusion), based on digitizations by Grégory Chaumet (PLEMO 3D / Centre André-Chastel) with scientific assistance from Élise Baillieul (University of Lille).

This experimental use of holographic technology, implemented by the company Holusion, was developed with the support of Sorbonne Abu Dhabi. Initiated as part of the preparation for the cathedral's reopening, it is the result of a scientific collaboration between Delphine Syvilay (Sorbonne Abu Dhabi), Jonathan Truillet (public institution in charge of the conservation and restoration of Notre-Dame de Paris), Dany Sandron, and Grégory Chaumet (Centre André-Chastel / Sorbonne University).