Reunited: The Ghissi Altarpiece
This is an overview of intellectual and technical adventures rooted in the project of organizing an exhibition at the North Carolina Museum of Art (NCMA) that reunites, for the first time in more than 100 years, the panels of the 14th-century Italian St. John altarpiece by Francescuccio Ghissi.
A more extensive write-up can be downloaded here. (7.4 MB PDF)
How it all started
The Ghissi altarpiece had been removed from its church over a century ago, and dismantled. The 9 individual scenes (one central scene crucifixion, and 8 smaller pictures featuring St. John the Evangelist) had been sawn apart; the resulting panels ended up in different collections. Three of the four panels from the Kress Foundation are now at NCMA; the fourth is in the Portland Art Museum. Three other small panels are with the Metropolitan Museum in New York; the larger central panel is in the Art Institute in Chicago. But 3 + 1 + 3 + 1 adds up to only 8, not 9 — the ninth panel (the last of the 8 smaller scenes) is lost. A Reunited Altarpiece could never be truly complete …
Reconstructing the lost panel?
To complete the altarpiece, NCMA commissioned the Dutch artist and art reconstruction expert Charlotte Caspers to “reconstruct” the lost panel. Together with NCMA curator David Steel she designed a composition in Ghissi’s style; the scene likely represented in the ninth panel could be determined from the Golden Legend, a medieval bestseller chronicling lives of saints, which was the source for the first 7 small panels.
Image analysis to the rescue
The Duke IPAI (Image Processing for Art Investigation) group could help with this, however! By studying the old as well as the new panels, we could virtually age the new panel — i.e. make a digital copy in which the gold would look duller, the colors would be altered to mimic 650 years of aging of the pigments, small cracks would be added. A printout could then “complete” the Reunited Ghissi Altarpiece, without distracting from its authentic siblings.
In the image below, move the slider to transition from aged and faded colors to the updated colors.
The following short videos, also available at the exhibition, describe the different components of the aging/rejuvenation process. These are described by the team of conservators, researchers, and students who worked together on the project.