Laser instruments were used to burn away the dirt and deposits, leaving only the rich colours of the frescoes beneath.
“When we started work, you couldn’t see anything – it was totally black. Different wavelengths and chromatic selection enabled us to burn away the black disfiguration without touching the colours beneath,” said Barbara Mazzei, who was in charge of the project. “Until recently, we weren’t able to carry out this sort of restoration – if we had done it manually we would have risked destroying the frescoes.”
At the centre of the ceiling fresco is an image of Christ, seated on a throne, with two men either side of him. They are thought to be either St Peter and St Paul or St Nerius and St Achilleus, two Roman soldiers who were martyred for preaching the new faith.