The video entertainment industry bet the farm on 3-D technology — and lost. Several years before his own death, film critic Roger Ebert wrote the obituary for this technology in an article titled: “Why I hate 3-D, and you should too.” Beyond the limited light levels available at the user end, and the required red/green glasses, Ebert lamented the creativity-sapping constraints that 3-D technology imposed on the cinematography itself, regarding coordinated camera positions, lighting, etc.
Instead of 3-D, he argued, we need higher resolution. Sadly, he didn’t live to see it, but today we do have ultra high definition (4K) video. We also have higher contrast capacity, and improved color differentiation. Together, under the right viewing conditions, and with the right source material, an impressive experience of depth perception can emerge from this combination of tech improvements — without all the complications of 3-D technology. I first saw this while demonstrating a new OLED TV display (featuring ultra high definition and nearly infinite contrast) in my own showroom, using a 4k Blu-Ray disc of The Great Gatsby. In certain scenes, the perceived sense of depth was palpable — and impressive. How is this possible?
Turns out that the human brain includes four different mechanisms for perceiving depth. The first, employed in 3-D technology, is called binocular disparity. Because of the distance between the eyes, the brain received two slightly different images of a scene, which it translates into the experience of depth. This phenomenon is not unlike the binaural disparity between the sound captured by the left and right ears, which the brain translates into a sense of space in stereophonic sound.
The second cue used for visual depth perception appears in almost every scene. It’s called interposition. The brain knows that an object positioned in front of another (second) object will block out the view of the second object, and infers that the object being blocked is the one that’s further away. This phenomenon is well known to aspiring actors, who are often visually blocked out of what they had hoped might be a break-out scene.
Renaissance painters employed a third cue, perspective, to create the sense of depth by rendering smaller and smaller objects, that were further and further away, until they vanished. This is sometimes referred to as the vanishing point. It too is ubiquitous, especially in outdoor scenes.
But what got my attention in viewing The Great Gatsby was the fourth cue to depth perception: textural gradients. When contrast and resolution are sufficiently unrestricted, people with normal vision can perceive subtle (sometimes not-so-subtle) variations in the color and texture of close-up objects. This visual richness diminishes for objects that are farther away; at some point, it is completely lost. This difference in perceived texture between near and far objects provides depth cues to the brain which can be quite dramatic.
This means that the new high-contrast, high resolution TVs and source materials can — under the right circumstances — portray impressive depth perception, without all the fuss and bother of 3-D technology. Roger would be proud.