As Smithsonian Magazine reported, experts restoring the Sistine Chapel this spring discovered that Michelangelo used custom multi-headed brushes while painting The Last Judgment. Paolo Violini told Smithsonian Magazine that parallel strokes with identical wobbles revealed the use of specialized tools with multiple tips, reaching nearly six inches wide with ten points. This equipment enabled the artist to replicate cross-hatching sculpting techniques on a flat surface. Researchers also examined hidden self-portraits within the mural. Fabrizio Biferali told Smithsonian Magazine that a self-portrait located in the cloak-folds of a figure representing Death was painted after the artist fell from the scaffolding and recovered during the course of the multi-year project.