FPS, can you tell the difference?

[Jammrock]

Different media uses different 'tricks' to mimic real life movement. Film runs at 24 fps, but between each frame is a dark/blank frame. I can't remember the exact term for it, but that dark/blank frame plays a trick on your mind that makes the 24 fps seem 'real'. Like the motion blur mentioned earlier.

TV uses interlacing to make images look real. There are a total of 30 fps on US NTSC, but because of the interleaving it only shows 1/2 of a frame per clock. So 2 clock cycles = 1 frame, thus the NTSC TV runs at 60 Hz, but only 30 fps. A slighty different method to cause a motion blur, thus trick the eyes and mind.

HDTV ~60 fps, because their signal is not interlaced, the same way a computer monitor is non-interlaced. To trick the mind into making the movement look real, they have to use a higher screen refresh, just like computers.

Anyway, it's been a long time since I studied all this. Different methods yield different results. The main reason 60 Hz is not acceptable for computers is because that's the same frequency that flouresent lighs use (yes, they blink like a CRT). After continued exposure the two different light sources start cancelling each other out, causing serious eye strain and 'black spots'.

Jammrock

[Genom]

I have dark brown eyes as well and can tell the difference between 80 and 100Hz. Although anything over 100 looks solid to me. Between 90 and 100 I can see it, only if the image is a very bright light colored one though.

Just to slightly correct ya Jamrock, Film is 24FPS, but blurring on film helps make it smoother. There isnt a extra black frame I'm afraid. Personally I think 24FPS for film looks like crap most of the time. But then again, I am a computer weenie who has been in the video market for a long time so I am trained to notice this sorta thing. But I can see a very noticeable flicker when I go to the movies. NTSC TV's are running 30FPS, but 60 Fields per second. Since the image is interlaced, you perceive it as smooth video. Each field is different, so you are seeing 60 discreet images per second.

HDTV uses various FPS rates,and is a whole other can of worms. FOr a very good layman's explanation, go here:

http://www.mar-con.com/HDTV.html

Party on!

[KvHagedorn]

Originally posted by Dr Mordrid
Just a question born of curiosity;

How many of you who say you can see refreshes >60-85 hz have blue or green eyes?

I ask because the FFF (fusion flicker frequency) for blue and green eyes is higher than for brown eyes at any given brightness level.

Once you get a frame rate >FFF the sequence blurs into smoothness. For interlaced displays this runs 26 fps for brown eyes and 28 fps for blue/green. For a non-interlaced display this doubles to 52 and 56 fps respectively.

I noted brightness because it is a primary factor in the FFF. At lower intensities the FFF is lower than at high intensities. Since most games like Quake, UT etc. spend a lot of time in dungeons and tunnels....

Dr. Mordrid

Mordrid, where did you get this piece of "Science"? What specifically is there in the amount of Iris pigmentation that makes such a difference here?

[Dr Mordrid]

I really don't like the implied sarchasm you attempted by putting Science in quotes. Tacky.

Getting the info is pretty easy. It's called research and it resulted in my reading some very interesting data in journal. I also taught anatomy & physiology for about 10 years.

Some online reading to get you started;

Basics: http://webvision.med.utah.edu/temporal.html#flicker

FLICKER FUSION RATE Definition (Sharp electronics):

"This is the rate above which the human eye can no longer recognize discontinuous changes in brightness as a flicker. Provided the frame frequency is above this rate, the eye integrates the signal into a consistent image. The flicker fusion rate is 31.25 Hz. The appearance of flicker can occur if the frame frequency is close to the frequency of fluorescent lights. That value can vary slightly between different individuals."

The rise and decay times involved in visual latency curves (rise = the delay between an event and the sensing of that event by the central nervous system. Decay = the falloff in the signal over time) varies from research paper to research paper, but they range from 25-80 ms rise time in most of them. Decay depends on the cell type being stimulated. Cone signals are faster to decay than rods.

The eye color difference is caused by a variance in the proportion of rods (luma vision) vs. cones (color vision) in people with eyes of different colors. This directly affects CFF/fusion is because of the differing decay times between the color and luma signals.

That lumance value affects CFF/FFF is dogma. It's called the Ferry-Porter law which states that the fusion frequency of a flickering light is proportional to the logarithm of stimulus intensity.

Dr. Mordrid

[KvHagedorn]

I'm sorry about the sarcasm, but I am instantly skeptical about any statement which is supposedly based upon unreferenced scientific fact, yet which is completely counter-intuitive. I had never heard of any correlation between retinal structure and the level of pigmentation in the iris, nor does it seem logical that this would be the case, unless there is some sort of genetic parallelism going on here, which is likely still pretty random. The only physical difference I could imagine being inherent to darker irises is light absorption, which might actually favor a dark-eyed individual when higher intensity light is the factor causing the CFF to be reached.

Your reference above was an interesting read, but still did not establish a correlation between iris pigmentation and rod/cone distribution. Is there truly another advantage to having blue eyes aside from attractiveness?

[Helevitia]

Is there truly another advantage to having blue eyes aside from attractiveness?

Yeah, there is. Having Brown Eyes I love Brunettes with dark brown eyes better than blondes or non-blondes with blue eyes.

[Admiral]

refresh rate:

I think the minimum should be 85Hz, 75 starts to look bad and anything below sucks.
I can notice the difference between 85 and 100Hz, it's not so disturbing, 85 vs 75 is.

fps:

I think a minimum barrier of 30fps is enough. It's the sudden dropp in fps, from 100+ fps to 20-40fps, when you go out in open spaces or the screen fills with characters, that makes me feel the lag. Or it just as well might be the lack of sideband addressing on my mobo

Oh, yes ! almost forgot. I'm blue-eyed too.

[Novdid]

I'm with Helevitia on the girls!!!

[frankymail]

Well guys, here's a little story that will make you think twice about your feminine-selection-criterias:

"In High School, I was going out with this girl and everything was going great. But after a while, the passion started to faded away and we split up. I told myself that I should find a girl with more passion.

In college, I met that girl, very passionate woman. However, she was too much passionate: she was always excited by little things, she was always crying for little things. And we split up. I wanted to date someone a little more stable.

Then, I met a much more girl, but after a while, we split up: thing were boring, she never wanted to do anything special, nothing. I told myself I should get a girl with more ambition.

And I finally met such a girl: we dated, got married and had children; eventually, she filed for divorce, got the children, my pride and all my money...

But I've learned my lesson. Nowadays, I'm only searching for a girl with big tits... "

[IcedEarth]

Originally posted by Dr Mordrid
Just a question born of curiosity;

How many of you who say you can see refreshes >60-85 hz have blue or green eyes?

I have green eyes and I am definately irritated when a monitor isn't at least set at 85hz. At my work most people work at 60hz and it bothers me just to look around the office. So whenever someone leaves his desk, I go change the frequency of that monitor. When I ask them, they don't notice the difference and I never understood why

[Ssin]

Originally posted by frankymail
But I've learned my lesson. Nowadays, I'm only searching for a girl with big tits... "

ROLL. Quote from a french rap song : "Tu es blonde à forte poitrine? Tu 'mintéresse!"

Translation : "You're a blond girl with big tits? Well I'm interrested in you!"

It's a song about a producer looking for new talents... well you get the idee.

[ChipHead]

Originally posted by Wombat
Caine,
A more important reason that films are okay at 25fps is because the images are blurred when the movie is filmed. Real film, with real exposure time, and the recorded image has the blur that your eyes expect.

...and because the cinema projector 'flashes' each frame twice, not once. That gives an 'effective refresh' (if I can call it that) of 48 fps (flashes per second??). Projected film is normally shown at a rate of 24 frames per second, by the way, not 25.

Regards,

Glenn.

[frankymail]

Actually it's 23.997 fps

[ChipHead]

Originally posted by frankymail
Actually it's 23.997 fps

Nope. It's 24 fps, exactly (or as exactly as the mechanisms will allow). You may be thinking of the NTSC television frame rate, which is 29.997 frames per second.

Regards,

Glenn.

[mariner]

LOL
brown eyes are slower ??
based on what ?