was involved in. Pellicioli reattached paint to the wall using a clear shellac, making it relatively darker and more colorful, and removed some of the overpainting. However, as of 1972, the repainting done in various restorations had made the heads of saints Peter, Andrew, and James differ significantly from the original design. Major restoration The painting's appearance by the late 1970s had badly deteriorated. From 1978 to 1999, Pinin Brambilla Barcilon guided a major restoration project to stabilize the painting and reverse the damage caused by dirt and pollution. The eighteenth- and nineteenth-century restoration attempts were also reversed. Since it had proved impractical to move the painting to a more controlled environment, the refectory was instead converted to a sealed, climate-controlled environment, which meant bricking up the windows. Then, detailed study was undertaken to determine the painting's original form, using scientific tests (especially infrared reflectoscopy and microscopic core-samples), and original cartoons preserved in the Royal Library at Windsor Castle. Some areas were deemed unrestorable. These were using watercolor in subdued colors intended to indicate they were not original work, while not being too distracting. This restoration took 21 years and, on 28 May 1999, the painting was returned to display. Intending visitors were required to book ahead and could only stay for 15 minutes. When it was unveiled, considerable controversy was aroused by the dramatic changes in colors, tones, and even some facial shapes. James Beck, professor of art history at Columbia University and founder of ArtWatch International, had been a particularly strong critic. Michael Daley, director of ArtWatch UK, has also complained about the restored version of the painting. He has been critical of Christ's right arm in the image which has been altered from a draped sleeve to what Daley calls "muff-like drapery". In culture The Last Supper has frequently been referenced, reproduced, or parodied in Western culture. Some of the more notable examples are: Non-modern painting, mosaic, and photography A 16th-century oil on canvas copy is conserved in the abbey of Tongerlo, Antwerp, Belgium. It reveals many details that are no longer visible on the original. The Roman mosaic artist Giacomo Raffaelli made another life-sized copy (1809–1814), commissioned by Napoleon Bonaparte, that resides in the Minoritenkirche in Vienna. Modern art In 1955, Salvador Dalí painted The Sacrament of the Last Supper, with Jesus portrayed as blond and clean shaven, pointing upward to a spectral torso while the