It's like this, but not really, but mostly...get it, good.
The human eye can detect specific frames of an image at less than 30(+/-5)fps. However, this does not mean you can't differentiate that something is still changing faster than that. This is why you can still detect a flicker on a 60hz monitor, however, I challenge you to be able to see the jump in the frames of a video/animation at 60fps, you simply can't. That said, the airforce (no linky, find it yourself) has shown that people can detect changes subconsciously and consciously in an image at over 200fps.