There isn’t that much difference between what you see with one eye and what you see with two. The mind provides 3D depth mainly from visual clues, which is what perspective imitates and what many optical illusions play with.
I enjoy your posts in other art threads; thanks for this. And :smack: to me for not adding chiaroscuro/use of light and dark as a factor in perceiving elements in a 3D space…
Aw, shucks. I think I pretty much hit the same 17 points everyone else had beaten me to, but with extra special jargon.
We don’t get a lot of hardcore arty threads here, and we haven’t had a good rousing “abstract art is teh suckxorzs!1!” thread in a while.
As an illustration of this: Stand in the middle of some railroad tracks, and look down them all the way to the horizon. Yup, the two rails converge to a point, just like linear perspective theory says it should. But now follow the line of the rails until you’re looking down at your feet: Now they’re parallel. And keep following them, looking between your legs at the opposite horizon: They meet at a point there, too. Now, two straight lines can meet at a point, but when you’ve got them meeting at a point in one end, going parallel in the middle, and then meeting at another point at the other end, well, those line’s ain’t straight any more.
This isn’t actually because the eye isn’t a point; no matter how pointlike you make an eye, you’d still have this effect. Ultimately, it’s a projection effect (basically the same as the problem of putting the globe on a flat map), and it’s because your eye is a finite distance away from the scene.
A few years ago I hiked through Horseshoe Canyon in southern Utah. When you get to the far end of the canyon there’s a solid cliff face with many “primitive” painted figures, known as the “Great Gallery.” The figures span about 80 horizontal feet, and some of them are about 7 feet tall. Nobody knows who painted them, but they predate the Anasazi by many centuries. They are amazing works of art, some of which contain very interesting geometric designs.
I was looking at the small group of figures shown on the right, and suddenly realized that the unknown ancient artist understood basic perspective. Then I remembered that even the “advanced” civilization of Egypt didn’t use perspective.
Either that or they were running out of space and started painting in smaller people because that’s all the gaps allowed. Or they wanted to show the relative power of the people, making the most powerful man large, and the least powerful small. Or some other thing that has nothing to do with perspective.
Guys 1, 2, 4, and 5 are all standing at about the same height and vary from near the smallest to near the largest sizes. Guy 3 is the same size as 2 and yet is much higher on the painting. Guy 6 is further down than both 2 and 3, and yet about the same size. Guy 7 is lower down than 1 and yet about the same size. In a perspective painting, people lower down should be larger. Ones higher up should be smaller. Simply put, there’s no demonstrable link between how far up or down on the painting the person is and their size.
I think another poster may have touched on this, but just as an aside Eastern artists seemed to have got a good understanding of perspective much eariler than they did in the west. This Wikipedia page has a list of important Japanese paintings, with some fantastic examples of perspective from much earlier than the European Renaissance.
Any examples in there of converging-orthogonals-with-vanishing point-style one-point linear perspective? Japanese painters tended to use a sort of perspective where their orthogonals stay parallel (like with those Genji scroll images there, a technique called fukinuki-yatai-- “blown-off-roof” technique)–really the same sort of empirical perspective that Medieval European artists used.
IIRC one point perspective of the European sort really doesn’t make it in until the Edo period with, um. . . especially Maruyama Okyo and that crowd who use it as a kind of novelty/gimmick (Okyo actually adopts a European style of painting with chiaroscuro, etc, but he’s weird). Even by Hiroshige’s day it’s seen as a novel foreign thing.
Orthogonals are just what they term the lines-into-the-distance which in one point perspective wind up looking diagonal and converging. I’m using it loosely.