Michelangelo’s “The Last Judgment” inside the Sistine Chapel is entering a new phase of restoration, with Vatican conservators removing a chalky white film of salt that has accumulated on the Renaissance fresco since its last major cleaning roughly three decades ago. The Vatican described the start of the operation to reporters on Saturday, saying the scaffolding required for the work is now blocking the full view of the chapel’s imposing heaven-and-hell scene while restorers treat the surface.
The Vatican Museum said the cleaning is expected to be completed by Easter, in the first week of April, and that the public will be able to keep visiting the chapel in the meantime. During the restoration, however, visitors will be shown a reproduction of “The Last Judgment” superimposed on a screen that covers the scaffolding, rather than seeing the fresco directly.
At the center of the work is the salt film itself, which Vatican Museum officials said has built up thanks to the conditions created by the chapel’s visitors. Fabio Moresi, who heads the scientific research team at the Vatican Museums overseeing the cleaning, said the salt is created when people sweat and emit lactic acid, and when that lactic acid reacts with calcium carbonate present in the wall. Moresi also pointed to climate change as a factor, saying visitors who come tend to sweat more and that additional humidity can increase the reaction that produces the salt buildup.
Vatican Museums chief Barbara Jatta described the film as a “cataract” and said restorers can remove it using a careful technique. She said conservators dip sheets of Japanese rice paper into distilled water, apply the sheets to the fresco, and then wipe away the salt film.
The Vatican said the difference is already visible in sections that have been cleaned compared with areas that have not been treated. Restorers demonstrated the contrast from the scaffolding level, showing parts of the fresco that appeared coated in chalky dust before the cleaning, while cleaned areas revealed more vibrant colors and finer detail. On the figure of Jesus at the center of the work, the Vatican said a visitor could see how Michelangelo painted his hair and the wounds of the crucifixion.
The Sistine Chapel is named for Pope Sixtus IV, an art patron who oversaw construction of the main papal chapel in the 15th century. Pope Julius II later commissioned Michelangelo to paint the ceiling, including the “Creation of Adam,” between 1508 and 1512. A later pontiff, Pope Clement VII, commissioned Michelangelo in 1533 to paint “The Last Judgment.”
The Vatican said other frescoes in the Sistine Chapel typically receive yearly cleaning, with restorers working at night and using removable cherry-pickers that can be put away each morning before the public arrives. Those machines, the Vatican said, cannot access all of “The Last Judgment” because the fresco sits behind the altar, which is raised above the floor on marble steps. That access challenge is what led the Vatican to mount a fixed scaffolding to reach the entire image for cleaning.
The Vatican said it last carried out a complete restoration of the Sistine Chapel between 1979 and 1999, when it removed centuries of smoke, grime and wax buildup. The Vatican said it also left small patches of the pre-restored fresco intact to show the earlier condition, and that those patches are visible on upper parts of the scaffolding and appear nearly blackened. Rather than reduce visitor access during this restoration, the Vatican said it is studying ways to address humidity levels—through filtration systems and other technologies—so the salty film does not form again.
As covered in a previous MSI report on the restoration’s start, the current operation is aimed at refreshing the fresco’s appearance after years of buildup that began clearing in the first Sistine Chapel cleaning in about 30 years.