Not so "Secret Knowledge"

Honestly, I wasn't too surprised to learn in David Hockney's video that 14th century artists used mirrors or a camera obscura to aid in the production of various paintings, nor was I offended or disappointed to hear so. tracing to "outline" a "topic" (if you will) doesn't devalue an exquisite, priceless piece of work or its creator. it just seems plausible to utilize any and all means available when becoming a true master or your craft. competition is a healthy, human trait and drives us to great lengths. progression means keeping up with the times, and i am sure it was no different then. these techniques and devices by no means developed or created any painting themselves. they were simply tools, and tracing allowed the artist to correctly proportion, place, and position the subject. the artist didn't trace light, shadows, or texture. sure he could shade an area to indicate such things, but not copy them (or cheat.) seems to me if you really think about it, they put even more work into their art by using these methods. the dedication it must take to strategically and accurately line up the correct image to the outline while still keeping patience with loss or lack of light and/or movement of the subject. and if I'm not mistaken the purpose (or idea) of cheating is making something easier. the endless mathematical calculations, in my opinion, outweigh the unorthodox approaches taken and add (rather than take away) to the silently awing beauty of the 14th century art.