Conservation-restoration of Leonardo da Vinci's The Last Supper until 1498. The scene is understood to depict the Bible verse John 13:22, showing the reactions of the Twelve Disciples, at the Last Supper, in the moments following Jesus’s announcement that one among them will betray him. When he received the commission for "The Last Supper", Leonardo da Vinci had never worked on a piece of this great a size, fifteen feet high by almost twenty-nine feet wide. He also had very limited experience working in the technique known as fresco, mixing pigment into wet plaster to create a permanent bond. Traditionally, fresco painters put down many successive layers of
Conservation-restoration of Leonardo da Vinci's The Last Supper plaster before and during the painting process. This method requires fresco painters to work quickly and with a pre-set plan. However, this is not how Leonardo worked, and because of that, he chose a new technique of putting a mixture of oil and tempera paints onto a dry wall. According to Ross King, “In essence, [Leonardo] took tempera paints and mixed emulsifying oils into them.” This allowed Leonardo to include richer colors, finer details, and at a slower work pace. Leonardo da Vinci first coated the wall with a coat of plaster. He then added a thin layer of calcium