In the David Hockney film, Hockney tried to recreate Reniassance paintings using a technique with mirrors. Hockney believes the artists during the 14th century did not paint their paintings by eye, but with equipment. Artists would use a mirror and old cameras , like camera obscura, to reflect an image and trace it. He backed up his argument with research. He noticed that many Reniassance paintings were normally 30 cm. That would be the standard size of the reflected image into camera obscura. He first noticed that Reniassance paintings had similar lighting and accurately portrayed depth. One example would be Jan Van Eyke. He was an artist that had amazing depth in his paintings, including the chandelier. With the use of this equipment and concave mirrors, paintings looked realistic. Detail and the texture in clothes were clearly seen and things looked shiny like "photographs".
When I heard about this technique, I was disappointed for a moment but the artists are still talented. A paintings can not be made without being invisioned. The artists sees the big picture and creates an image. The talent is still there and it is not cheating. Art historians can notice some use of camera obscura in the 17th century because the image is fliped when traced. So, there are too many left handed pictures to be normal. Some paintings also have wrong proportions with lengthen bodies and other optical distortions. Artists have their own methods in making their paintings. They can produce a 3 D image on a 2 D surface, which is amazing anyway. Perspective was something the Reniassance Painters mastered.