Art and reality has been a theme for many studies, theories and discussions since the Greeks but artists show with their work what it takes ten chapters to be explained.
René Magritte, the famous surrealist painter, did many works about the illusion of art.
This excerpt explains "The Human Condition", 1933 at the right:
"At first, one automatically assumes that the painting on the easel depicts the portion of the landscape outside the window that it hides from view. After a moment's consideration, however, one realizes that this assumption is based upon a false premise: that is, that the imagery of Magritte's painting is real, while the painting on the easel is a representation of that reality. In fact, there is no difference between them. Both are part of the same painting, the same artistic fabrication. It is perhaps to this repeating cycle, in which the viewer, even against his will, sees the one as real and the other as representation, that Magritte's title makes reference." (emphasis mine)
Ben Heine, Belgium like Magritte, has a series Pencil vs Camera, I did this post about it, where he adds some elements to his photographies with drawings and than take a picture of his creation:
"I took this photo near Rochefort in Belgium. I also drew the roughsketch on the crumpled paper. I wanted to make something very simple and minimalist. We always need a sun!"
Still, it's a photography. Art is about creating, not copying.
Text sources: Magritte.
(Click at the pictures to enlarge)