My basic idea is a picture of a painting/sculpture/etc. with the basic info on it (title, artist, dimensions, location) and, after the jump (cut for you LJ/DW users), a closeup of the bit that the artist screwed up or dropped the ball on, with some text explaining why (and maybe even why it probably wasn't a priority for the artist - in some cases, if you spend too much time on an unimportant aspect, it takes away from the focus of the painting, in other cases the painting was meant to be viewed from way down below on the ground, so some liberties with perspective were taken).
And maybe even some things where artists break the rules to great effect - there were a couple of paintings by Caravaggio followers in the exhibit (one was a copy of the other, actually) where the rule that you never have a strong diagonal leading directly off the corner of a picture was broken. Normally you don't do this because it takes the eye of the viewer out of the picture. In these cases, the strong diagonal leading off the page was an angel pointing out heaven to a saint about to be martyred. In this case you want the viewer heading off the canvas and up towards God. Although preferably after spending some time circling the action in the painting first.
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