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Piranesi's Perspective Trick (2019)

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Re: Piranesi's Perspective Trick (2019)

#3
In the image with the caption:

  "Normal homography perspective transformation produced in GIMP. Note how squashed the buildings at the right and left are when taken in isolation"
The building at the right is not squashed ? It is wider than in the Piranesi picture above.

Re: Piranesi's Perspective Trick (2019)

#4

In the image with the caption: "Normal homography perspective transformation produced in GIMP. Note how squashed the buildings at the right and left are when taken in isolation" The building at the right is not squashed ? It is wider than in the Piranesi picture above.

They mean distorted, not squished for both.

Re: Piranesi's Perspective Trick (2019)

#6

In the image with the caption: "Normal homography perspective transformation produced in GIMP. Note how squashed the buildings at the right and left are when taken in isolation" The building at the right is not squashed ? It is wider than in the Piranesi picture above.

It would have been nice to show a few more easy-to-understand comparisons. The "street view" image was nice, but blurry. Ditto with the map. I think if the last image of the two buildings had been shown side-by-side with the "correct" perspective, that might have helped explain the article.

Re: Piranesi's Perspective Trick (2019)

#8

In the image with the caption: "Normal homography perspective transformation produced in GIMP. Note how squashed the buildings at the right and left are when taken in isolation" The building at the right is not squashed ? It is wider than in the Piranesi picture above.

> The building at the right is not squashed ? It is wider than in the Piranesi picture above.

The building on the right is squashed, in isolation. When you take the building by itself (in isolation), it is indeed wider than the picture above, but it is also the same height, i.e., squashed.

Re: Piranesi's Perspective Trick (2019)

#10
> By legibility I mean that the Piranesi distortion is easier to read, and that to anyone unfamiliar with photographs, that hasn’t grown up with TV, photographs and magazines, the Piranesi version would look much better, and the true perspective would look rather odd.

I think this is a key point that people are often unaware of. For instance, whenever I see a modern artist who has painted photorealistic art, I read discussion about how amazing it is that this artist can paint something so perfectly life-like, and the Renaissance artists were clearly inferior, since they couldn't paint with such skill.

Besides the obvious discussion about the purpose of art, the other question is whether a photorealistic painting is actually more "lifelike?"

Sure, it represents the world exactly the way that a camera sees it, but does it represent the world exactly as we see it? With our human brains we are filling in details, we are focused on the subject of the painting, we are distorting, we are re-mapping shades of color to what we know they ought to be. "Lens blur" in particular isn't remotely the way our eyes perceive the world: our eyes can never roam around the unfocused parts of our own image, rather we ignore the blurry parts unless we specifically try to notice them, and anything we try to focus on becomes sharp.

So I appreciate the authors recognition that Piranesi's perspective may indeed be closer to how we perceive the world than "correct" perspective.

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