Quote:

Originally Posted by Joe Bloggs /t/1484182/why-we-need-1000fps-1000hz-this-century-valve-software-michael-abrash-comments#post_23591446





Isn't that just for 1080p?



What about the optimal fps for 4K and 8K? Click to expand...

There are a lot of variables, so there's no single answer.The more resolution you have, the more pixels of motion blur you get at the same angular motion. The angular motion blur is the same, but since the angular motion covers more pixels (more density), you're not hitting the necessary sweet spot of less than 1 pixel of motion blur for fast panning to look exactly as sharp as stationary images to the human eye. The visual acuity of the human eye also plays a role, so beyond a certain point, it doesn't matter, but as long as individual pixels are big enough to be resolved, Mike's correct that you need higher Hz for higher resolution, to keep "pixels-of-motion-blur" the same for the same angular motion speed, and if you're trying to hit the sweet spot of less than 1 pixel of motion blur (imperceptible), there you go... (e.g. strafing and turns in games, as well as when turning your head using VR goggles as Michael Abrash was talking about) This is talked about by John Carmack at about 12mins into his YouTube For moderately fast motion of 960 pixels per second, CRT's (and LightBoost 10%) manages to hit the motion clarity sweet spot where http://www.testufo.com/#test=photo *AND* http://www.testufo.com/#test=photo&pps=0 have exactly the same sharpness either moving or stationary (no judder, no stutters, no streaking, no blur, no ghosting, no overdrive).Even at [email protected] , you can mathematically still have human-perceptible motion blur during high-def computer graphics moving at 2000 pixels/second if your eyes are able to track that fast *AND* the pixels themselves are resolvable. Since 1ms equals 1 pixel of motion blur for every 1000 pixels per second, since your eyes have tracked 1/1000th that distance, causing that pixel to smear. If one pixel is big enough to be resolvable, then blur will be noticed in that pixel if the eye tracking accuracy is good enough and the motion is fast enough. At 2000 pixels/sec, there is 2 pixels of blur at [email protected] sample-and-hold, so even that might still not be the final frontier; it's still a finite-refresh display with diminishing returns, but not disappeared returns required for HoloDeck quality.Some people may be familiar with the Blur Busters pursuit camera tests at PHOTOS: 60Hz vs 120Hz vs LightBoost , which actually surprisingly corresponds well with what the human eye sees when directly viewing the ghosting pattern at www.testufo.com/#test=ghosting But head turning at only 30 degrees per second on a 1080p VR googles, the motion blur becomes immediately noticeable in fast pans (much like the motion blur at www.testufo.com/#test=photo which on modern LCD's the motion blur is caused by eye tracking, not by the display response speed.) because it envelopes your vision and your head turns forces panning (a motion blur torture test case).Not everyone does eye-tracking during fast motion on screen. But the problems of discrete-framerate (even at 240, 480, 960) displays conflicting with the non-framerate nature of human eyes -- this problem becomes noticeable during head-turning in VR -- or when people use computer monitors at close-distances and want fast FPS gaming (strafing/turning) to be as perfectly sharp as stationary images.There are scientific extreme cases where, humans would notice non-Holodeck-perfect limitations at beyond [email protected] , due to the stroboscopic effect / wagon-wheel effect, but generally speaking, [email protected] woiuld probably eliminate the vast majority of problems for Holodeck-like simulations. You could intentionally add 1 millisecond of motion blur (which is tiny) to fix any remaining stroboscopic/wagonwheel effect problem of discrete-refresh displays, and the motion blur increment would be small enough to not be objectionable except during the fastest head turning.Mathematically, 1ms equals 1 pixel of eye tracking motion blur with display motion of 1000 pixels/second (1 pixel per millisecond)(Assuming pure strobes -- on then off, no decay trails, no aftereffects, no sample-and-hold beyond this time)-- How big are the pixels? 2K vs 4K vs 8K-- How sharp is the source material? Unfiltered computer graphics is easier to see blur in, than during video.-- How fast is the panning? Faster panning creates more eye-tracking motion blur on displays.-- How fast can you track your eyes accurately? That defines your upper limit when pans are too fast for eyes to track. (That's the moment of sweet spot)-- How accurate is your eye tracking? (saccade factor) Different people are much more accurate at eye tracking, the shiftiness/jerkiness of the eyeball motion.-- How much angular vision is covered? It's easier to notice motion blur in faster pans in wider displays that span your vision, because you have more time to track eyes accurately.-- Etc. Other variables exist.All the study of Vision Research stuff (e.g. people who use www.vpixx.com products and similar)