3D Tutorial: 3D & Depth Perception
Rather than routine step-by-step instruction on how to create 3D objects or letters, this 3D tutorial introduces important basics that are not well understood by most artists—beginners and professionals alike. From there, this knowledge can be applied to any kind of 3D illustration, from 3D computer graphics to photography.
What 3D Means
3D refers to those three dimensions of height, width and depth. (right) In this 3D tutorial, depth specifically refers to "distance from our position."
A convincing 3D appearance can be an impressive effect to achieve, especially upon a surface that is completely flat. Here we are attempting to convey a sense of reality with space and depth on something which actually has none.
For that reason, "3D" has even implied a certain emphasis on depth. After all, depth fulfills an object's three-dimensional state.
By introducing a sense of depth, you create space and an extension of reality into your art, enhancing your audience's participation. When things appear more real, they become real to your audience's senses to some degree, even if below their conscious awareness. This pulls your audience in, letting them experience what may have only previously existed in your imagination. This also just tends to look more interesting and inviting.
A new concept in this 3D tutorial, is that apparent depth comes from what is called, "difference with distance." This simply means closer things appearing different from farther things. For example, an object which is close will look different in size compared to one farther away. (right) Almost anything we can do to make things "different with distance" will create depth. Through fog, levels of visible detail are becoming different by reducing as objects get farther away from us.
Next, note that apparent depth is most commonly evident by assigning less of something with more distance. The most obvious example is that things look smaller as they get farther away. This stems from the fact that an amount of something is reducing compared to the increasing distance between us. So through fog, details are becoming less clear with more distance.
Next, as distance from us increases, there appears to be less depth. This will make things look more flattened. This also makes closer things look more 3D. For example, to the left is a box up close while below is shown how that same box might look from a great distance away.
Therefore, the greater the depth is away from us, the less depth perception we will have.
Depth perception means detecting "difference with distance." For example, the more size differences that can be identified, the greater depth perception we will have. (below left) Within a flattened image, such differences are less evident. (below right) The fewer visible differences there are, the less depth there appears to be and the less 3D our image becomes.
This tells us that depth perception is not just about how good your eyes are or how excellent your judgment might be. It is also about how much evidence of depth is actually there in the image to recognize.
A depth cue is any kind of "difference with distance" we can recognize.
Following this 3D tutorial, more depth cues will be described.