Polygnotus and Delphi
Polygnotus, along with Mikon, was the most appreciated painter of classical Greece (5th c. bC). He was nicknamed ethographos, that is the one who captures the mood and character of his models.
It is known that these masterpieces were refreshed (i.e. partially repainted) by artists sent by Monarchs of Hellenistic era, when the original colours started faiding out. That is the reason they were still visible when Pausanias visited Delphi in 2nd c. BC. Pausanias is giving a vivid description of these paintings.