Restoration of the Sistine Chapel frescoes of the work. Based on this decision, according to Arguimbau's critical reading of the restoration data that has been provided, the chemists of the restoration team decided upon a solvent that would effectively strip the ceiling down to its paint-impregnated plaster. After treatment, only that which was painted "buon fresco" would remain. According to critics, the inherent problem with this approach is that it relied heavily upon an assumption that Michelangelo only painted "buon fresco", that he was always satisfied with the result at the end of the day, and that in four and a half years spent on the
Sistine Chapel Choir "Any kind of guerilla action against Vatican II does not produce good fruits. The council's principles by now are untouchable." In 2010, Massimo Palombella, a Salesian priest, was appointed to replace Liberto as head of the choir. In September 2015, Deutsche Grammophon released a CD recorded in Sistine Chapel with the choir, the very first recording allowed there. Authorised by Pope Francis, he ruled that profits from sales of the album must be used for charity purposes only. On September 26, 2017, the Sistine Chapel Choir made their first visit to Canada, hosted by St. Michael's Choir School, at St.