Trompe l’œil painting (literally meaning “fool the eye”) must be approached with a sense of humor: we should be amused when we discover the tricks being played on our senses, and stand in awe of the fresco masters who managed to transform paint and fresh plaster into stone, flesh, cloth, and air. Many of these frescos are also mathematically challenging, as artists were forced to warp their subjects in the creation of false perspectives, viewed correctly only from a great distance away.
Here are some details from the ceiling frescos at Vienna’s Karlskirche, which I was able to to view at eye level while it was being cleaned. The subjects’ faces were particularly striking in their exaggerated configurations – drawn to be viewed only from many stories below, where the perspective would appear correct. I was personally impressed by the sketch-like gold leaf detailing on the faux bronzes, and the faux marble cornice paintings that looked as full and vivid at eye level as they did from the pews.