Light and Sight
Please answer in one paragraph.

Obviously, painters have almost always had an intense consciousness of light and how they want to portray or use it. Rememberchiaroscuro, a couple of centuries before this era? In terms of composition and technique, what were some of the radical elements in the Impressionists’ use of light? They had some rather unique (for their time) views on the subject, and light’s interaction with the eyes, and how that impacts (or should impact, in their view) a painting.
It is relatively common for the new, radical generation of artists to be disapproved at first by the guardians of the status quo. That label – “impressionism” – was first used derisively. Can you think of other examples of this? What reasons – artistic or otherwise – might cause this regularly occurring phenomenon in the arts?