This image illustrates a Camera Obscura, which is a chamber completely obscured except for a little hole, with a specially prepared glass plate placed in front of it. This device shows people walking along the street inside the chamber, but they walk upside down, on their heads. This indicates how Man, after his original sin, became obscured in his heart and reason. He has become an upside down image, namely, from the image of God he became the image of Satan.
(Johannes Arndt, Wahres Christentum, 1606-1609)