> frame rate. As all I learned the human brain is only capable to recogise a frame
> rate from 24 to 26 per second due to individual differences.

That's not really true, below about 24 fps it doesn't look like fluid 
motion, rather a sequence of images changing quickly. IIRC up to about 
100 fps (obviously it varies from person to person) your brain can still 
get more information and make the motion look smoother and more 
real-life-like. It's relatively easy to demonstrate the difference 
between 30 fps and 60 fps on a normal PC, and if you have a new LCD or 
old CRT capable of 120 Hz you can demonstrate that too.

But, above 100 fps does make a difference for fast moving parts when 
your eye is tracking the motion. In real life if an object is moving 
very fast your eye tracks the movement very accurately and you can see a 
perfectly sharp image of the fast moving object. If you try the same on 
a film/video/tv it looks blurred (even if you have infinite resolution 
and zero response time) because the image is only being updated every X 
metres (where X is the distance moved by the object within one frame). 
Your eye is continuously moving but the object is moving in finite steps 
- this is what makes it look blurred.

Film makers at 24 fps purposely have to avoid objects moving quickly 
relative to the screen exactly because of this effect. It's the same 
reason why you get LCDs running at 480 or 600 Hz to reduce motion blur.

Post a reply to this message