The Uncanny Valley

I recently came across a term used in robotics that I found both fascinating and highly relevant to the field of digital effects.

The Uncanny Valley is a term and a hypothesis which states that when robots and other digital likenesses of humans look and act too much like actual humans, but not exactly, it causes a response of revulsion in human observers. The "Valley" is the actual dip in the graph charting human reactions to these likenesses.

When a digital likeness is created that is far from human (think a doll or a Saturday morning cartoon character) it is far enough from an actual likeness of a person that viewers react positively. Get closer and closer to an actual likeness and before you arrive at a likeness indistinguishable from a real person, you fall into a valley where your creation looks kind of like a person, just wrong. And the reaction of viewers is visceral fear.

This theory is good for anyone developing avatars, animated characters or even just photo editing to keep in mind. Straying far from reality is okay and sticking to reality is okay too, but slight deviations from what is real can be a dangerous place to play.