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Why Some Avatar: Fire and Ash Scenes Look So Smooth, and Others Don't (gamesradar.com) 62

If you watched Avatar: Fire and Ash in James Cameron's preferred high frame rate 3D format and noticed certain sequences appearing unusually smooth while others had the traditional cinematic look, that visual inconsistency is entirely intentional. The third Avatar film continues Cameron's frame rate experimentation from The Way of Water, selectively deploying 48 frames per second for underwater and flying sequences while keeping dialogue scenes at the standard 24 FPS.

The human eye perceives somewhere between 30 and 60 FPS, meaning viewers can detect the shift between frame rates. Cameron argues the tradeoff is worth it: discomfort from 3D viewing isn't eye strain but "brain strain," caused when parallax-sensitive neurons struggle to process jumping vertical edges. Higher frame rates smooth this out. When critics questioned the approach, Cameron was characteristically blunt. "I think $2.3 billion says you might be wrong on that," he told DiscussingFilm, referencing The Way of Water's box office.

Why Some Avatar: Fire and Ash Scenes Look So Smooth, and Others Don't

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  • 30/60fps (Score:5, Informative)

    by darkain ( 749283 ) on Monday December 22, 2025 @02:33PM (#65875305) Homepage

    "The human eye perceives somewhere between 30 and 60 FPS"

    This is absolute bullshit. Humans can track significantly faster than this, its just that at around 24 frames a second (assuming proper motion smoothing from captured footage), things START to appear animated rather than a series of stills.

    There is a reason why 240Hz monitors exist. Check out Blur Busters tests, such as https://testufo.com/ [testufo.com] - on a 240Hz OLED panel there is a distinct difference between 120Hz and 240Hz. And now we're pushing monitor tech well beyond this level of refresh rate.

    There have also been countless tests done to show that higher framerates in fast paced games has a measurable impact on human processing latency.

    • This is absolute bullshit.

      I tend to agree. Figure a game running at 120 fps, you can detect a dropped frame, easily.
    • Re: 30/60fps (Score:5, Interesting)

      by reanjr ( 588767 ) on Monday December 22, 2025 @03:07PM (#65875411) Homepage

      It's not bullshit, it's just imprecise. Your fovea sees higher frame rates on a very small point your are directly looking at, but the wider picture frame rate does start to become very difficult for the vast majority of people to see the difference at around 60 fps.

      • system 1 sees more than system 2. You can detect higher frame rates and notice things are unnatural and off with system 1 but system 2 is too slow to recognize much which is why subliminal images can be picked up but not noticed.

        The blur of reality vs a fast rate slide slow don't align with how we live; plus there is a visual blanking humans do when our eyes dart around in our heads and the misalignment between framerates and device blanking (or strobes to hide LCD blur) is likely to sometimes bring out stu

    • This is absolute bullshit. Humans can track significantly faster than this, its just that at around 24 frames a second (assuming proper motion smoothing from captured footage), things START to appear animated rather than a series of stills.

      And this helps explain all the clips of dogs and cats (apparently) actually watching TV. They need even higher frame rates to perceive motion, which many modern flat screens offer. A quick Google search returns various sources saying dogs need at least 70-80Hz and cats at least 100-110Hz to perceive motion, also noting that they, like many animals, see colors differently than humans.

      • Many birds, like pigeons, see everything around 120hz+. That's why you almost never hit birds with your car. They perceive the world in something like "slow motion" and they are able to get out the path of your vehicle very quickly.
        • Huh? First off birds do get hit by vehicles, but that aside .. even humans can see cars approaching. Therefore the fact that they can see cars coming into their trajectory isn't proof of high fps perception. I am not saying they don't have high frame rate perception, they probably need it for head stabilization and to detect a predator starting to spring towards them, or prey movements. https://www.reddit.com/r/oddly... [reddit.com]

      • I think that one was more about image persistence. Old screens flashed one bright image each frame. Then LCDs showed the frame the entire time and suddenly animals could perceive it as more than a strobe light.
    • The whole human eye only perceives X fps is complete and utter nonsense that somehow keeps getting perpetuated. To make 24 fps in a film look like motion there is constant trade off such as making individual frames blurry to substitute motion. People can easily pick out 1000 fps/hz if the motion is moving fast enough across the screen.
    • This is absolute bullshit. Humans can track significantly faster than this, its just that at around 24 frames a second (assuming proper motion smoothing from captured footage), things START to appear animated rather than a series of stills.

      This is also incorrect. The point at which something looks animated or not has a lot to do with not just the frame rate or speed of motion, but also the shutter angle. You saw that quite clearly in the early days of DSLRs being used for video where the still photo people had no idea what they were doing with video and shot at frame rates below 60fps with shutter speeds of 1/1000th to freeze the motion. When you do that you see even 60fps can look like a slideshow.

      Conversely if you have significantly higher

    • There is a reason why 240Hz monitors exist. Check out Blur Busters tests, such as https://testufo.com/ [testufo.com] - on a 240Hz OLED panel there is a distinct difference between 120Hz and 240Hz. And now we're pushing monitor tech well beyond this level of refresh rate.

      There is no 120Hz content let alone 240Hz and no prospect of this changing anytime soon. The primary benefit of displays with a native frequency of 120hz and higher is 24Hz is an integer multiple of the native frequency avoiding judder caused by various pulldown schemes. Now when people play around with movies with 48Hz frame rates viewers now need a 240Hz panel to avoid judder that was solved with 120hz panel. Nobody is being helped by this.

      Motion blur is a natural part of human vision and is baked into

    • Yes. Human eyes can perceive between 300 600 changes per second

    • There have also been countless tests done to show that higher framerates in fast paced games has a measurable impact on human processing latency.

      Higher framerates will look more natural. Even if one can only see frames at 60 Hz, in real life, a fast moving object will active a trail of receptors. At 60 Hz, most games will typically cause fast objects to just jump to new positions. This is unnatural and could cause tracking problems. Doesn't mean we are perceiving at higher than 60 Hz.

  • I saw the first Avatar movie and thought it was pretty good.

    Just recently, I watched the second Avatar movie and I could not enjoy it because the whole thing seemed artificial. The CGI was rampant and it was bordering cartoonish.

    I read recently that the third film as filmed at the same time as the second, so I presume that it looks as bad or worse than the seconds. I won't be in any hurry to watch it.

  • do all projectors deal with that mode swtich fine or do they fall back into an more basic mode for the rest of the movie?

  • by Cyberax ( 705495 ) on Monday December 22, 2025 @02:48PM (#65875355)
    I never understood why people were against higher FPS. They look objectively better! The real world is more than that, after all. And the argument against is apparently just "because soap operas were filmed at higher FPS, and soap operas are uncool".

    Like, really? You're expecting younger audiences to care about soap operas from 80-s?
    • by bjoast ( 1310293 )
      Agreed. I remember when The Hobbit films came out. I loved watching it at 48 FPS in the theater, but there was neverending complaints from many people back then.
    • Because at this time, budgets aren't high enough to make higher rates look real. You can no longer rely on Hollywood magic to make something look real. Every prop, set, and face must be actually real, not some quick and cheap Hollywood trick.

      A gnarled tree wrought of plastic can look real at 24 fps. It won't at 60 fps. That means your set people can't rely on their old cheap plastic moulding strategies. They must instead figure out an alternative strategy, like filming on location.

      • by Cyberax ( 705495 )
        I'm not buying that. I guess higher FPS were a problem when every frame had to be reviewed and retouched on an actual celluloid film. But that hasn't been the case since the early 2000-s. We also have a bunch of movies shot at higher FPS and later downscaled for the theatrical release. They look just fine at higher FPS.

        It really was all down to "soap operas are uncool".
    • It was never about high FPS in a vacuum, but people don't know that so it just becomes HFR=bad for them. The thing missing is *shutter speed* needs to also adjust. By no means is it static, but if you show people 24fps @ 1/48 shutter and then 48fps @ 1/96 shutter, they won't be complaining about soap opera effect.

      The challenge is that you need to do shooting, VFX, compositing, etc. in HFR and then apply some fake motion blur to the LFR version to make it seem more correct, and that's never going to look per

    • I really liked the hobbit at a higher FPS also, but I can see how some people were put off by certain scenes that somehow felt lower quality due to the higher frame rate.
    • It's got nothing to do with uncool as much as it has to do with uncanny valley effects. When you start blurring the boundary between real and fake it does create a very real sense of unease in people.

      Personally I'm on team high frame rate and support pushing through it to the point of maximum realism.

  • 3D viewing isn't eye strain but "brain strain," caused when parallax-sensitive neurons struggle to process jumping vertical edges. Higher frame rates smooth this out. When critics questioned the approach, Cameron was characteristically blunt. "I think $2.3 billion says you might be wrong on that," he told DiscussingFilm, referencing The Way of Water's box office.

    So... Cameron's saying people flocked to it for the frame rate, not the story? :-)

  • For the 24 fps scenes, AI could come up with the in-between frames so I hope they do that when it comes to streaming. They'll have to remove his stupid "no AI was used.." disclaimer.

    • Eh you don't even need AI to do this. There have been filters in premier that have been doing that for decades. Even plenty of opensource software. Not saying AI would be better or worst, just that you can get away with saying "I used a filter!" even if the filter was by AI:P

  • Why do we have to re-visit this every time it is used in a movie effect? I mean this is common enough now that we literally have created a cinema standard Dolby Vision 2 to allow directors to variably control motion smoothing (perceived higher frame rates) on TVs.

    What is tomorrow's story going to be about, why are are using colour in movies?

  • This annoyed me so much with the previous film, there's no way I'll bother seeing this one. It just jars you out of the immersion every time the framerate changes... Disappointing that Cameron still thinks he's right on this one. How the mighty have fallen...
  • I watched it with my daughter. The way the FPS kept changing was very distracting, to the point where I was wondering if the projector was lagging. But it's intentional? That's intentionally stupid. Don't intentionally break immersion.

  • Cameron et el are cough up in their own world of issues nobody but themselves give a shit about.

    It reminds me of Noland randomly switching aspect ratios between scenes and thinking he was accomplishing anything other than annoying movie goers or those who insist on intentionally filling scenes with grain for effect.

    Directors should focus on things people actually care about like the ability to understand spoken dialogues and reigning in the CGI bullshit.

  • I was too busy waiting for it to be over to notice any difference in frame rates.

  • That Americans use such a backwards format for television. It would be great if they could catch up by about 45 years with the rest of the world and get 30FPS as standard.

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