It is Tintoretto’s own studio. The original drawing was made by one of his helpers, Odoardo Fialetti, and was copied and used as an illustration for the first drawing manual* ever published in Italy (1608).
Here is a peek into the sort of school that all the Renaissance masters attended. As you see, it is a very busy place. There are students and helpers of all ages—one of them is just a child.
An older student helps the beginners and corrects their drawings of the plaster casts. A shophand kneads clay or grinds colors. The old master sits at his easel while a helper prepares another big canvas or finishes some area the master has left to him.
“Find a good master,” an old artist’s manual advised apprentices, “and then stay with him as long as you can.”
* Il vero modo et ordine per dissegnar tutte le parti et membra del corpo