Recently, a cluster of unrelated events have turned my thoughts to the visual perception of space. To be honest, it’s always been a preoccupation. For several months I’ve been using the Escher print pictured above as my computer desktop image. It’s an elegant depiction of the world of the surface, a higher world that is seen mirrored in the surface, and a third world that is glimpsed in the depths. This can be taken as a simple image of the beauty of transparency and reflection, or it can be related to the cosmology that is common to shamanic cultures worldwide, where the world of our everyday experience exists between and influenced by both an upper realm of celestial patterns and an underworld of earthly spirits. Our prehistoric and ancient ancestors have left us evidence of their engagement with the upper world through their sophisticated models of the movements of heavenly bodies, and of their journeying in the lower world through caves populated with powerfully rendered animal spirits.
I’ve always been fascinated by paleolithic art, and have posted about it previously, so of course when I heard that Werner Herzog had made a documentary film about the Chauvet Cave, the oldest painted cave yet discovered, I knew this was a film I had to see. Here’s a publicity still of the director posing with an archaeologist who appears in the film dressed in an ice age fur suit and plays a reconstruction of a 35,000 year-old vulture-bone flute (sound file at the link).
You’ll notice that Herzog’s cinematographer, in the background, is holding a camera that has two side-by-side lenses. That’s a 3D or stereoscopic camera. We perceive depth partly through the way our brains process the input from two eyes offset from each other by a few inches, and 3D photography, which has been around nearly since the invention of photography, simulates depth perception by showing each of our eyes a slightly different view of the scene.
I’m not particularly fond of the current 3D digital projection processes - there are several variants, all of which I find rob the cinematic image of much of its brightness and color, and are generally distracting and tiring to the eyes. (Not to mention that a lot of films these days are shot normally, and then turned into fake, simulated 3D, which can look really terrible.) But in Herzog’s film, Cave of Forgotten Dreams, the technique is effective in giving us the feeling of what it’s like to be inside the cave, and of how the artwork is integrated into the organic bulges and hollows of the limestone walls. It’s the closest most of us will get to being able to be inside a real paleolithic painted cave.
One effect of seeing a 3D film is that it can make you more conscious of depth perception in everyday life. But here’s something different and odd. I went with a friend to take a look at this new sculpture, Echo, by Spanish artist Jaume Plensa, that’s been installed through August 14, 2011, in Madison Square Park in Manhattan. It’s a 44-foot (13.4 meter) tall head of a child, with eyes closed and a tranquil expression. My friend said she couldn’t escape the illusion, when seeing the statue from a distance, that it was flat, like a cutout, and I had the same experience. Seen from up close, it’s clearly three-dimensional, but from a distance it has an eerie, unreal quality. It is surely an uncanny object.
It appears that the scale of the vertical dimension is approximately double the scale of the horizontal dimensions. Plensa uses 3D computer modeling to create his works, and here he has started from a realistic form, elongating it and softening the edges of the features. The surface of the sculpture is cast in polyester resin and coated with white marble dust. The reflective, almost translucent-looking whiteness, the simplicity of the forms and the serene blankness of the expression, the monumental size, and the lack of a pedestal all help to make Echo look like an eerie vision. I believe the illusion of flatness is caused by the elongated scale. We’re used to seeing huge flat pictures on billboards, and often from angles that distort the images in ways similar to the distortion of Echo. When we see a huge face distorted, our minds assume that we are seeing a flat image from an oblique angle. We are so habituated to seeing things that way that it is difficult to overcome the illusion even when we know what we are looking at.
Another eerie white object that appears flat even though we know it is round is the moon. I came across this photo recently on the fantastic Nasa Astronomy Picture of the Day site, a bottomless fountain of beauty on the web. If you look at this picture with cheap red-cyan 3D glasses (available free here), the moon looms out at you like the sphere it is. Of course the moon is far too distant for the normal parallax separation of our eyes to reveal its shape through stereoscopic vision. The picture here is constructed from shots of the moon taken two months apart. The natural wobble, or “libration” of the moon provides two angles of view, producing a 3D image that could never be seen in reality.
Yet another recent stimulus to my thinking about the visual perception of space and depth was Daniel Maidman’s recent post about approaches to pictorial space in painting. I urge you to click the link and go through the well-chosen example images – click on the small pictures to embiggen them. You’ll learn a lot about the subject by reading through Daniel’s entertaining overview, and if you’re a visual artist of any kind yourself, you’ll probably also find it highly stimulative of creative ideas. Daniel’s blog is really worth following. He’s as good a writer as he is a painter, easy to read, funny, and thought-provoking.
A lot of what I learned about pictorial space I learned by studying photography. In photography one of the biggest factors affecting the way space is presented is the choice of lens – a shorter focal length, or wide-angle lens, gives a very different effect than a longer focal length, or telephoto, lens. Here’s a street sign photographed with a wide-angle lens. A wide angle lens literally takes in a very broad cone of vision. For an object to appear large in the frame, it needs to be seen from very close, while the wide field of view includes a generous swath of background. Perspectival angling of lines is emphasized, and the apparent distance between background and foreground is exaggerated.
A slightly longer focal length lens allows us to fill the frame with a similar-sized object from a greater distance. Here the cone of vision is narrower, and thus the amount of background we see is limited and the perspective appears compressed, with the background seemingly right behind the subject. Many professional photographers tend to favor long lenses, because they isolate the subject from all the distracting stuff around it. Long lenses also make it easier to throw the background out of focus, which enhances the isolating effect.
A wide lens lets you see a whole tall building from right across the street, or to get a feeling of space within a tight interior. Any angle that’s not straight-on will show perspectival diminution. Translating the view below to a drawing would require three-point perspective, with vanishing points to the left, right and above the frame.
A long lens keeps straight lines straight, but tends to flatten the space of objects seen from a distance, as in this view looking towards the Manhattan Municipal Building from Canal Street.
Finally we get to some figure drawing. Aside from perspective effects, which you can sometimes observe in seeing the body from a foreshortened angle, there are several ways to convey three-dimensionality in a drawing. I generally try to make my shading and coloring lines follow the surface contours of the subject. These lines are called cross-contours, and they’re a very effective way to create the illusion of solidity.
Lighting effects also help to show the spatial form of a subject. Just as the differing angles of the two eyes create the stereoscopic effect, different colors or qualities of light coming from more than one angle can give solidity to a two-dimensional depiction.
In the drawing below, perspective, cross-contours, lighting, and negative space are all combined to give a sense of the model as a solid presence occupying space.
This is probably one of the most wide-ranging posts I’ve ever done, but I hope it hangs together around the concept of spatial perception.
All the images that are not my own link back to their sources on the web if you click on the pictures.