I thought it might be interesting to round up a few depictions of ancient artists at work.
First up is a portrait painter. This panel depicts him in his studio in the 1st century AD in Kerch (Bosporan Kingdom). On the wall hang portraits he's painted, including Imagines Clipeatae which usually survive carved. He also uses an easel. (Hermitage Museum)
This red figure cup shows a Greek bronze sculptor in his workshop, carving a statue of a horse (by the Foundry Painter, found in Vulci, now Staatliche Antikensammlungen Inv. 2650 - source):
Sculptors also sometimes depicted themselves working, as in this 2nd century AD frieze from a sarcophagus found in Ephesus (Istanbul inv. 775):
We also have a view ancient depictions of iconoclasm. Ironically, this details from the 9th century Chludov Psalter is also evidence for ancient painting techniques since the mosaic of Jesus is being white-washed.
The Goleniscev Papyrus has a well known depiction of Theophilus standing over the Serapeion, destroyed on his instructions.
The iconoclasm of Byzantine Christians was of course based on the Old Testament prohibition of images, so it's not surprising the a panel from the Roman synagogue at Dura Europas showed the destruction of the temple of Dagon: