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Despite the promise of this making visual media feel more real, I can't help but feel like, for games, this makes the video games look like a cheap approximatio

Despite the promise of this making visual media feel more real, I can't help but feel like, for games, this makes the video games look like a cheap approximation of over-edited movies. For things moving real fast, or real close, or especially with non-ego motion, this all makes sense. But it is over-used for things like "the character turns quickly". When I snap my head (or eyes) around, I don't see a blurry image, I see the new image, and my brain drops the intermediate data. You can test this by looking at yourself in a mirror, focusing on one eye, then another. Do you see your eyes or face or anything blur? Adding blur just delays the presentation of the new view when moving your POV in games. It's distracting and unrealistic.

throwaway8481 3y ago
I feel like motion blur should be used like mouse acceleration. Like you said: If I whip my head around quickly that image should present clearly and immediately. However, if I'm in a car or flying through the air (in a game) this may distort the image as I'm glancing. This is the kind of drag-as-you-accelerate blur I'm expecting, and it can really make a fast-paced moment look that much more exciting. Motion blur is poorly executed everywhere.
sxp 3y ago
> You can test this by looking at yourself in a mirror, focusing on one eye, then another. Do you see your eyes or face or anything blur? This isn't the best test since your brain compensates for saccades by censoring input for a while. And it has built-in motion stabilization which allows you to read a sign while walking down the street. A better test would be to look at your finger or hand while waving it very quickly. You'll see motion blur as your finger moves. In certain cases, you can see individual "frames" as an afterimage. E.g, if you look at a modern car tail light, the LED isn't on consistently but uses PWM to blink really quickly. So if you move your eyes while looking at a tail light at night, you'll see a series of dots rather than a blurry image. Once you learn this trick, you can distinguish between analog lights and PWMs by noticing if they are blurry or discrete.
- jvanderbot 3y ago
  I'm more referring to FPS obsession with blurring things when the character moves, for that, turn your head quickly: Do you see a blurry room? I do not. Because your eyes must also move, and as you say, the brain censors because a "turn and look" includes an eye movement (I hypothesize). For fast moving things outside of ego motion, I can see a reason to use blur (e.g., your hand waving).
  - SamBam 3y ago
    That's a good point, but how would turning your head in a first-person perspective ever look good in a game? As you say, when we turn our own heads our eyes naturally saccade. But I'm not sure having this done unnaturally -- e.g. by having a couple static intermediary images -- would look right at all. But smooth isn't right either.
    - jvanderbot 3y ago
      It would rely on the eye's natural saccade. My brain drops the intermediate frames already and I mostly just see the new perspective. just like real life. Adding blur makes the motion stand out.
      - SamBam 3y ago
        Except that your natural saccade is also wired to your motor neurons in your head and neck. For example, there's a strong connection between the neurons that fire to turn your head 10⁰ to the right, and the neurons that fire to turn your eyes 10⁰ to the left, which allows your eyes to fixate on something even as your head moves. Indeed, it's almost impossible to turn your head slowly without your eyes fixing on points in your field of view, and then saccading to the next point. Try it. This is a hard-wired response. (You can perform some tricks to do it, like completely blurring your eyes, but that's not really the point.) Meanwhile, if we watch a video with the camera turning, it's easy to keep our eyes staring straight ahead. This shows that there is going to be a difference between a head naturally turning and watching a video of a head turning. I think you're describing saccades as just being the "dropping out" of frames, and not including the extremely-relevant motion that our eyes do during a saccade.
Log_out_ 3y ago
Actually you do not see a new image, you see a amount of details and your brain rewrites the history of what you saw so there is continuity.
Wowfunhappy 3y ago
In video games, I find motion blur helps to compensate for lower framerates. It's particularly necessary at 30 fps, but nice even at 60 fps. On the rare occasion I've been able to play a video game at 120 fps—my projector is limited to 60hz, sadly—I've found that I prefer to play without motion blur.
Sohcahtoa82 3y ago
Motion blur is a contentious subject in games because it's often done very poorly. The biggest three crimes are blurring an object too far, blurring things that shouldn't be blurred, and blurring an entire scene (which I guess just results in #2, so maybe there's really only two crimes). The most important thing is that motion blur should be subtle. Properly-done motion blur doesn't make a game look blurry, it makes it look more real and smooth. If an object is moving 50 pixels between frames, then the blur should not be more than 50 pixels wide. Really, it should likely be only 25 pixels to make the blur more subtle. But for some reason, racing games love to apply a full radial blur to an entire scene while going fast, and to me it just ruins it. Likewise, an object that is not moving relative to the camera should have no motion blur at all. This is where so many games get it wrong. As you rotate, they blur the scene using post-processing. In a completely static scene, this makes sense and is a very computationally-efficient way to perform motion blur. But if you're rotating because you're tracking an object, the tracked object should not be blurred. If you're in a racing game and the car next to you is going the same speed as you, the other car should not be blurred. Really, the only guaranteed way to get correct motion blur is to render multiple entire frames in a row and then blend them, but you need a LOT of samples to make this look good, or else something like a vertical line looks like a series of vertical bands as it flies across the screen, rather than a smooth blur. The best is probably a hybrid approach. Render each object in the scene on its own and apply a post-process blur on a per-object basis based on which direction it is moving relative to the camera. Though Z-ordering could end up becoming a major challenge.
- account42 3y ago
  > As you rotate, they blur the scene using post-processing. In a completely static scene, this makes sense No, it doesn't make sense because due to eye movement that's not how turning looks in the real world. Any game that blurs the scene on camera rotation is doing it wrong even if nothing else is moving at the time. It's impossible to do it correctly without very low latency and high precision eye tracking so the best you can do is to not blur anything that the player might be focusing on.
  - subb 3y ago

throwaway8481 3y ago

I feel like motion blur should be used like mouse acceleration. Like you said: If I whip my head around quickly that image should present clearly and immediately. However, if I'm in a car or flying through the air (in a game) this may distort the image as I'm glancing. This is the kind of drag-as-you-accelerate blur I'm expecting, and it can really make a fast-paced moment look that much more exciting. Motion blur is poorly executed everywhere.

sxp 3y ago

> You can test this by looking at yourself in a mirror, focusing on one eye, then another. Do you see your eyes or face or anything blur? This isn't the best test since your brain compensates for saccades by censoring input for a while. And it has built-in motion stabilization which allows you to read a sign while walking down the street. A better test would be to look at your finger or hand while waving it very quickly. You'll see motion blur as your finger moves. In certain cases, you can see individual "frames" as an afterimage. E.g, if you look at a modern car tail light, the LED isn't on consistently but uses PWM to blink really quickly. So if you move your eyes while looking at a tail light at night, you'll see a series of dots rather than a blurry image. Once you learn this trick, you can distinguish between analog lights and PWMs by noticing if they are blurry or discrete.

jvanderbot 3y ago
I'm more referring to FPS obsession with blurring things when the character moves, for that, turn your head quickly: Do you see a blurry room? I do not. Because your eyes must also move, and as you say, the brain censors because a "turn and look" includes an eye movement (I hypothesize). For fast moving things outside of ego motion, I can see a reason to use blur (e.g., your hand waving).
- SamBam 3y ago
  That's a good point, but how would turning your head in a first-person perspective ever look good in a game? As you say, when we turn our own heads our eyes naturally saccade. But I'm not sure having this done unnaturally -- e.g. by having a couple static intermediary images -- would look right at all. But smooth isn't right either.
  - jvanderbot 3y ago
    It would rely on the eye's natural saccade. My brain drops the intermediate frames already and I mostly just see the new perspective. just like real life. Adding blur makes the motion stand out.
    - SamBam 3y ago
      Except that your natural saccade is also wired to your motor neurons in your head and neck. For example, there's a strong connection between the neurons that fire to turn your head 10⁰ to the right, and the neurons that fire to turn your eyes 10⁰ to the left, which allows your eyes to fixate on something even as your head moves. Indeed, it's almost impossible to turn your head slowly without your eyes fixing on points in your field of view, and then saccading to the next point. Try it. This is a hard-wired response. (You can perform some tricks to do it, like completely blurring your eyes, but that's not really the point.) Meanwhile, if we watch a video with the camera turning, it's easy to keep our eyes staring straight ahead. This shows that there is going to be a difference between a head naturally turning and watching a video of a head turning. I think you're describing saccades as just being the "dropping out" of frames, and not including the extremely-relevant motion that our eyes do during a saccade.

Log_out_ 3y ago

Actually you do not see a new image, you see a amount of details and your brain rewrites the history of what you saw so there is continuity.

Wowfunhappy 3y ago

In video games, I find motion blur helps to compensate for lower framerates. It's particularly necessary at 30 fps, but nice even at 60 fps. On the rare occasion I've been able to play a video game at 120 fps—my projector is limited to 60hz, sadly—I've found that I prefer to play without motion blur.

Sohcahtoa82 3y ago

Motion blur is a contentious subject in games because it's often done very poorly. The biggest three crimes are blurring an object too far, blurring things that shouldn't be blurred, and blurring an entire scene (which I guess just results in #2, so maybe there's really only two crimes). The most important thing is that motion blur should be subtle. Properly-done motion blur doesn't make a game look blurry, it makes it look more real and smooth. If an object is moving 50 pixels between frames, then the blur should not be more than 50 pixels wide. Really, it should likely be only 25 pixels to make the blur more subtle. But for some reason, racing games love to apply a full radial blur to an entire scene while going fast, and to me it just ruins it. Likewise, an object that is not moving relative to the camera should have no motion blur at all. This is where so many games get it wrong. As you rotate, they blur the scene using post-processing. In a completely static scene, this makes sense and is a very computationally-efficient way to perform motion blur. But if you're rotating because you're tracking an object, the tracked object should not be blurred. If you're in a racing game and the car next to you is going the same speed as you, the other car should not be blurred. Really, the only guaranteed way to get correct motion blur is to render multiple entire frames in a row and then blend them, but you need a LOT of samples to make this look good, or else something like a vertical line looks like a series of vertical bands as it flies across the screen, rather than a smooth blur. The best is probably a hybrid approach. Render each object in the scene on its own and apply a post-process blur on a per-object basis based on which direction it is moving relative to the camera. Though Z-ordering could end up becoming a major challenge.

account42 3y ago
> As you rotate, they blur the scene using post-processing. In a completely static scene, this makes sense No, it doesn't make sense because due to eye movement that's not how turning looks in the real world. Any game that blurs the scene on camera rotation is doing it wrong even if nothing else is moving at the time. It's impossible to do it correctly without very low latency and high precision eye tracking so the best you can do is to not blur anything that the player might be focusing on.
- subb 3y ago