Which artists work were used to demonstrate differences between shallow space and deep space?

Traditional paintings (prior to the late 19th Century) usually portrayed a sense of depth or 3-dimensionality –  foreground, middle ground and background.  Once cameras were invented, painters began to explore ideas other than the reproduction (however beautiful) of a specific person or scene.  Many painters chose to flatten the space in the picture as they wanted to emphasize the idea that a painting was just that: a painting.  It does seem ironic that after the struggles of painters in the Middle Ages and Renaissance to develop depth in their work, just a few centuries later artists would be eschewing such pictorial ideas!!  In fact, some of them even pushing in the other direction with reverse perspective such as David Hockney has played with.

Explanation:

answer: 55

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