: Here's how we answer it: 1-Create a system that renders a windows desktop
: with "perfect" framerate-dependant motion blur on the mouse.
: 2-See if people can still distinguish 60/120/240/480/whatever FPS against
: each other.

: It would be a hard test to be sure to do right though. There's all kinds of
: stuff you'd have to think about, like making sure your motion blur levels
: are reasonable and aren't perceptibly making the image blurrier than an
: infinite-framerate non-motion-blur image would be (Obviously you could
: make even 30fps look perfectly smooth if you just smeared everything
: horribly). You'd also have to run the test on displays with very
: non-blurry motion response, like CRTs or plasmas.

Aye. Presuming an ideal display, this is what I believe the brain would pick up (and how humans can still identify higher screen framerates far above discernible framerate perception)