This allows the cinematographer to capture two images simultaneously to give the illusion of depth.

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The ancient Greeks and Romans understood this technique for creating the illusion of depth, but the skill was lost until Brunelleschi rediscovered it.

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That creates the illusion of depth.

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However, these feelings never lasted long, because the shot would switch to another camera position which had worse contrast, or greater lens distortion, or shallower depth of field, and the illusion would be broken.

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The biological basis for this complementary color effect is not well understood, nor is the depth of shadow, which is also an illusion.

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