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Framerates Matter
An anonymous reader writes "As more and more games move away from 60fps, the myth of the human eye only being able to detect 30fps keeps popping up. What's more, most people don't seem to realize the numerous advantages of a high framerate, and there's plenty of those."
Not sure how much it matters to sales, though.
Looks like it's Slashdotted already. Here's the cached page: http://74.125.47.132/search?hl=en&q=cache%3Awww.significant-bits.com%2Fframerates-do-matter&aq=f&oq=&aqi=
HOWEVER
The human mind is evolutionary designed to make instant assumptions. Cat in mid air facing us = DANGER. No "Is it dead and being thrown at us?" No "Is it a picture?" As such, video games can quite easily take advantage of this evolutionary assumptions and trick the MIND, if not the brain. into thinking something is real.
So while a higher frame rate will increase the quality of the game, it is not essential. It's like getting gold plated controls on your car's dashboard. Yes it is a real increase in quality, but most people would rather spend the money on a GPS device, real leather, plug-in-hybrid engines before you get around to putting gold in the car.
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I couldn't agree more. That Internal Server Error looks way better at 120 Hz on my 45" HD display.
"Until the become conscious they will never rebel, and until after they have rebelled they cannot become conscious"
You can tell the difference between 30 FPS and 60 FPS.
The way I tested this was I made a 2 second video in flash, a circle moving from the left side of the screen to the right side. 60 frames. Run it at 30 FPS.
Then I made a second 2 second video, same exact positions. 12 Frames. Ran it at 60 FPS. Asked me, and all of my surrounding classmates, which was about 24 students IIRC.
100% of us noticed a visible difference in the smoothness. Whether our eyes were making out each individual frame perfectly or blurring some together to create a smoother effect, it was irrelevant since there WAS a noticable difference. I was going to slowly bump the 30 and 60 FPS up higher and higher to see at what point the difference is not distinguishable, but I got lazy (High school student at the time.)
The point I think most gamers would agree on is that more frames per second are nice - but that 30 frames per second are Necessary. You can occaisonally dip down to 24 and be alright (24 is supposedly the speed that most Movie theatres play at) - but when you get around 20 or so its really does take away from the experience.
15 FPS vs 30 FPS vs 60 FPS. This is a visual representation. There are points made, however, that when you watch a movie, the image is "softened" and runs at a lower framerate [something like 24 or 25 FPS?] because your brain helps "fill in the gaps" or something of that sort. Pretty interesting stuff.
Everyone says a "framerate" (i.e., sample frequency) of 44.1kHz is all that is needed. Yet many people hear better imaging, depth and transparency at higher sample rates.
More to the point, the eye does not work with frames. The eye itself has no framerate.
Rods and cones individually update at about 15 times a second, but each individual one is entirely asynchronous from all the others. One update, another update, another update, etc. Your entire eye is not read 15 times a second, each individual light sensor 'trips' 15 times a second, semi-randomly, and sends the current light level. (1)
While each rod and cone only sends one signal, and then nothing, until it resets and sends another, our brains seems to assume that the light and color levels have remained the same.
Hence we get a 'blur', as objects move, and our brain assumes that said object is also in the old position until all rods and cones have updated.
1) And even that's not entirely right. Each rod and cone is actually sending a sorta average of the light it received since in the last update. You don't have to receive a photon exactly as it updates.
If corporations are people, aren't stockholders guilty of slavery?
I am a visual neuroscientist (IAAVNS). The standard idea of refresh rate comes from CRT based monitors where the image is drawn by a scanning electron beam. If you use an instrument to measure the instantaneous brightness at a given point on the screen it will rapidly peak as the beam swings by, and then decay as the phosphor continues to release absorbed energy in the form of photons. Different monitors have different decay rates, and, typically, CRTs that were designed for television use have pretty slow decay rates. CRTs that were designed for computer monitors typically have faster decay rates. If the decay rate were very very fast, then the hypothetical point on the screen would be dark most of the time and only occasionally very bright as the beam sweeps by on each frame.
As you can imagine this highly impulsive temporal profile is hard to smooth out into something closer to the constant brightness of the world around us. The human retina has an inherent dynamic response rate to it, but it's actually quite fast, and there have been studies showing clear responses in higher order visual areas of the brain up to 135 Hz. But standard phosphors used in CRTs have a little smoother response, and so at more-or-less 80 Hz, the brain stops seeing the flicker (at 60 Hz most people see flicker on a computer monitor). The exact refresh rate where perceptual blurring happens (so the flickering goes away) varies widely between individual, and with the exact details of the environment and what is being shown on the screen. More-or-less at 100 Hz refresh, no one sees the flicker anymore (although the brain can be shown to be still responding).
Contemporary screens, however, are LCD based (I'm going to ignore plasma screens since the field is still working out how they interact with the visual system). Making the same experiment as above, the temporal profile of brightness at a given spot on the screen will look more like a staircase, holding a value until the next frame gets drawn. This is a far, far smoother stimulus for the visual system, so a 60 Hz frame rate produces a perceptually far more flicker-free experience. That's why most CRTs at 60 Hz make your eyes bleed, while LCDs at 60 Hz are just fine.
Except that newer LCDs have LED backlighting which is no longer constant, but flashed (WHY? WHY? WHY? Just to save some power? Please, computer manufacturers, let *me* make that decision!), so the experience is somewhat more like a CRT.
So that's one part of the equation: flicker.
The other part of the equation is update rate, which still applies even there might be no flicker at all. Here, we have the evidence that the brain is responding at up to 135 Hz. In measurements made in my lab, I've found some responses up to 160 Hz. But the brain is super good at interpolating static images and deducing the motion. This is called "apparent motion" and is why strings of lights illuminated in sequence seem to move around a theater marquis. The brain is really good at that. Which is why even a 24 Hz movie (with 48 Hz frame doubling) in a movie theater is perceptually acceptable, but a 200 Hz movie would look much more like a window into reality. On TV you can see the difference between shows that have been shot on film (at 24 Hz) versus on video (at 30 or 60 Hz). Video seems clearer, less movie like.
For games, 60 Hz means 16 ms between frame updates -- and that can be a significant delay for twitch response. Further, modern LCD monitors have an inherent two or three frame processing delay, adding to the latency. As we know, long latency leads to poor gameplay. Faster updates means, potentially shorter latency, since it is a frame-by-frame issue.
So, just as with audio equipment where inexpensive low-fidelity equipment can produce an acceptable experience, while a more expensive setup can create the illusion of being at a concert, so too inexpensive video equipment (from camera to video board to monitor) can produce an acceptable experience, while a more expensive setup can create the illusion of visual reality.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
more accurately - most film cameras don't have a notion of a shutter 'speed'.
The film roll still goes by at 24fps, but the actual shutter is a wheel. That wheel can have various sizes of gaps (to increase/decrease exposure *time*) and sizes (to produce specific motion blur effects; e.g. an object leading its own motion blur path requires a small shutter opening at first, ending in a large shutter opening). You use fairly sensitive film and a small shutter gap, and you'll get nearly motion blur-less shots like that of Saving Private Ryan (watch explosions in that film and every speck of dirt that gets thrown about appears almost razor-sharp; some find this objectionable). Heck, you can even expose twice per frame if you want to get all experimental and stuff.
That said.. you can't - short of electronic shutters - expose for -more- than the film's fps, though. A bit under 1/24th of a second is the most you'll get (that 'bit' being required to transport the film to the next frame).
Anyway.. wiki: http://en.wikipedia.org/wiki/Rotary_disc_shutter