New Learn Article: Depth Perception

Italian Car
Have you ever wondered about what you see and what surrounds you? How is it that we can just tell that something is further away from us than something else?

Take a look at the photo to the right - how can you be certain that the brick wall is behind the car? Could it be possible that the car is behind the wall, and that you are viewing it through a car-shaped hole in the wall? The amazing thing about our visual systems is that we don't even waste time considering that as an option.

Depth perception is our ability to see (or perceive) how far objects are (or their depth). A depth perception cue is a hint to our visual systems that help us see depth.

Back to the car photo- we can thank our visual systems for the depth perception cue of occlusion. The fact that part of the wall is occluded, or out of sight, by the car lets you know that the car is closer to you than the wall.
L.A. traffic jam
Let's look at another example of a depth perception cue and examine this photo of a traffic jam in Los Angeles. With the texture gradient depth perception cue, our visual systems recognize that textures change as the recede, such that they become smaller and are change color. Because there are so many cars in this photo, we can think of this as a 'texture' - just as a sandy texture is composed of thousands of sand granules. Can you see how the cars get smaller the further away they are? And that it is more difficult to tell the color of each car the further back you look?