| Welcome to the wacky-world of Curvilinear perspective! This is a complex but dynamic system for rendering certain 3-dimensional situations in a 2-dimensional medium! This system maps an image into a circle with 4 VPs at the cardinal headings N,W,S,E and one at the circle origin.|
If you're starting here -- I recommend that you take a few minutes and go through the Perspective Primer on this site. It introduces you to some of the jargon and fundamental topics that are used here.
This section is intended to be an introduction to this system -- not a tutorial. I believe that the artist must first be expert in 1-, 2- and 3-point perspective systems before even contemplating trying this one! What follows is simply an introduction to the topic.
Imagine yourself standing in front of a very long brick wall. The wall extends far to your left and far to your right.
Imagine yourself looking to the left. See how the wall is rendered using 2-point perspective? Our center of interest is on the horizon, so we can use 2 points. The section of wall that is to our left looks pretty convincing here.
Imagine yourself now looking to the right. See how the wall is rendered using 2-point perspective? Our center of interest is on the horizon, so we can use 2 points. The section of wall that is to our left looks pretty convincing here.
See what happens when we try to connect our two views of the wall? What looked correct, each by itself, becomes discontinuous when we try to combine our two views. We know that the wall is flat, yet our combination yields a corner!! Why??
Seriously, the discontinuity arises because the vanishing points that represent our lateral views are constantly shifting as we turn our head. The VP locations above for our LEFT and RIGHT pictures are correct ONLY for that exact angle that we are looking at above. If we looked only halfway as far in either direction, the VPs for those shots would be in different locations.
Here's a power of the system -- it accomodates the shifting VPs as our eyes wander around the shot. For the immediate focus of our eyes, the drawing is in correct perspective, just as it would look if you were on the real scene.
Look at the wall near the center. See how the perspective is slight, just as you would expect if you were looking at the flat wall just a little bit to one side.
Now, look farther down the wall. The farther away from the center you look, the stronger the perspective becomes. Cool, eh?? This effect represents more accurately what you see when you are looking at reality.
Summary!Curvilinear (5-point) perspective is very powerful, as it more closely represents our vision in reality. And, it can be forced to yield the "wide-angle" camera lens distortion, creating a very interesting visual effect.
Wanna learn more?? Well, get yourself a book of architectural photos that have a large selection of wide-angle photos and study the distortion yourself! You can figure it out! I did!