Human eye's frame rate detection tolerance

[hobbes78]

Hi!

I remember having read a web page linked from doom9 where it was said the human eye cannot be given a certain number (e.g., 72 Hz) to the lowest frame rate it can distinguish. The example given was that of a military experiment, where someone was kept in the dark for a few hours and then the image of an airplane was displayed during 1/400th of a second and the person was able to correctly identify the image as being a plane.

Can someone point me to the address of that page?

Thanks in advance,

André

[ppera2]

Title of thread and what you describe is not same thing...

One shot and framerate....

I think that it is complex thing. Many thing depends from person, it's age, psychophysical condition and state etc.

[Doobie]

Movies are a 24fps framerate, and that is real annoying if there's no motion blurr during fast action. The boobs who come up with the digital movie standard should have doubled, or tripled, the frame rate instead of keeping it the same. They missed a good oppertunity (I bet they were too worried about the size of uncompressed video).

72fps is nice, but not beyond what can be detected by the human eye, even a poor human eye. Your video card and monitor should be able to support 120fps in some video modes, yet you could still detect flicker (especially with bright images). I don't know, maybe even 400fps wouldn't be enough to fool a good eye.

[Joe Fenton]

Well, I DEMAND 20480x10240 at 1000Hz progressive video!!! :mad:

:rolleyes:

Let's be realistic here people. You're lucky new standards in HDTV call for 30Hz progressive, or 60Hz in some cases. The days of 72Hz or better are decades off. You won't live to see 400Hz.

[mpucoder]

Originally posted by Doobie
The boobs who come up with the digital movie standard should have doubled, or tripled, the frame rate instead of keeping it the same Who says they didn't? Mpeg-2 allows framerates up to 240fps progressive.

[Shinigami-Sama]

Originally posted by mpucoder
Who says they didn't? Mpeg-2 allows framerates up to 240fps progressive.
is that a standard for broadcast though?
I think that was what he was gettign at
I mean I can see scaning 24fps
hell I can see it on my 70hz moni too..

[Tuesday]

my 2p:

When doom 3 came out ID annonced that 60fps would be enough for smooth motion so they where limiting screen updates to that while playing in multiplayer to prevent syncronisation problems between players.

I must say however i can usually get annoyed with games being "framey" when they are running at anything less that 100fps at a resolution my monitor can display at 100Hz.

As I would think most people are paying more attention to the picture and sitting a lot closer to the screen while gaming the "best" fps for movies is probably less than this, but certainly it's time to upgrade the 24fps value, and probably kill interlacing all together.

50fps progressive would do me nicely :)

[Doobie]

Originally posted by mpucoder
Who says they didn't? Mpeg-2 allows framerates up to 240fps progressive.

I was thinking of the standard for digital film for the theater. Whatever the technology allows, the standard is 24fps. This is all the more pathetic because it isn't be any better than HDTV that people can watch at home.

[ppera2]

Originally posted by Tuesday
....
50fps progressive would do me nicely :)

Typical European narrow thinking... :D

I thought about something dividable by 30 and 25, maybe 24 too.

150 fps could be good for 30 and 24 - so poor, moneyless people still be able to watch conversions (decimations).

I think that this thread gone too far in desires. There must be some reason why high framerates are not forced, but high resolutions are.
Maybe because relevant people is too old :confused:

[scharfis_brain]

50 (or 60) fps are totally sufficient, if the shutter speed is set correctly to 1/50 (1/60) sec.

also, the human eye is not able to distinguish framerate higher than 50 fps which are refreshrate-linked on impulse displays like CRTs (or maybe Plasmas).

so there won't be much difference between a 60fps Quake game on a 60 Hz-driven CRT
to an 120fps Quake game on a CRT driven with 120Hz refresh rate.

Only the flicker on the 60 Hz CRT will annoy us.

So there is no need for higher framerates than 60Hz.

There is only a need for good realtime motion-interpolators, that double the inputted framerate for 120Hz (NTSC) and 100Hz (PAL) Displays.
Very modern TV Sets do have this feature implemented already! (Philips Trimension)

But nonetheless Cinematig content 25p (24p) should never be interpolated to match the refreshrate. It would destroy the film-look. Also the chance to get visible motion artifacs from the motion interpolator will be much more present!
25p (and 24p) should always be synced to 100 Hz by 4 times frame repetition (and 120 Hz by 5 times frame repetition).

for sure, Computer games will fast and better calculate 120 fps than doing 60 fps with motion interpolation afterwards!