Crysis? Oh man. ENB'ed Skyrim turns my graphics on, not Crysis. Also, a cheap motion blur is not performance hungry, not the proper one i beleive.Frank wrote:Motion blur is one of the less performance hungry effects, if done well. In many games when I enable it I get zero performance hit. (Planetside 2, Crysis 2, Warface, etc).
As for the first part of your post. I didn't quite understand what you mean, but I think you said that motion blur is already there, created by your eyes when you look at something "moving" fast on your screen. Truth is that the screen is basically pixels quickly changing colors, there is nothing actually moving, so there is obviously no motion blur in games, except if added by the developer. By creating motion blur in games, the illusion of 3D objects moving instead of pixels changing colors gets enhanced even more. And this can help at low framerates, when the illusion of moving objects given by frames is less visible. I hope you understand what I mean, my english isn't the best.
For the other part: what's the difference between pixels moving on the screen, and object moving? Your eyes perceive light, it's all about light. In both cases you see the light, not pixels/real objects. If pixels move fast on your screen, you will see the same motion blur as from the real objects. And, probably, even more of it, because our displays suck.