Clip from Robert Hughes's "The New Shock of the New." @ 2:40: Hockney says of the camera, "You're more aware of what's at the edges, what's not there. It is forced to be a certain kind of picture." (More of Hockney on this subject in Lawrence Weschler's excellent compendium of interviews with the man, True to Life)
Then, from the introduction to the 1991 edition of Hughes's The Shock of the New
The enthusiasm for TV as a means of conveying information and opinion about the visual arts that I felt while making the original series of The Shock of the New has waned. Without accepting the extreme view...that everything that can be shown or said about art on TV is a pernicious lie, I now realize that the optimistic hope I set forth above, that in some way the distortions of the artwork inherent in TV reproduction would cease to matter, as they largely have in print reproduction, has turned out to be wrong. The wish was father to the thought. By stressing the iconic content of art, by forcing images meant to be slowly contemplated into merely narrative frames, and thus imposing the fast time of TV on the slow time of painting and sculpture; by eliminating surface, texture, detail, and authentic color, by working against the resistant physical presence and scale of the work of art, and above all by the brief attention-span it encourages, TV... cannot construct a satisfactory parallel to the experience of the static artwork. This would not matter in a culture that did not confuse TV with reality. Unfortunately, America does. But the fuller truth about art is in museums, studios, galleries, and books, and cannot be fitted on the screen.Each of our eyes perceive the three-dimensional world of our senses as a two-dimensional projection, given depth (and thus a third dimension) by our brain interpreting the stereoscopic vision given by both eyes used together, the overlap of objects in our visual field (a mental projection of what we think must be beyond), and the size of objects in that field (related to memory and experience-- we know that something is farther away if it appears smaller than we know it to be). Lost, in our translation of a two-dimensional representation that is not our own (i.e., photography or video), are all of the irreproducible elements ("texture") of the scene. These simply cannot be simulated.