24 is not the minimum. I personally can see the frames on a 24 or 24*(1000/1001) fps video if it changes quickly enough.
Comment on Apple’s engineers carefully designing the last 60 Hz OLED screens on the planet
spankysalmon@fedinsfw.app 2 days agoI mean, it’s still true, but everyone who cited it didn’t understand what it was saying. 24 is the minimum where your brain easily puts the motion together and it actually feels like motion. It’s also roughly near where your brain can still process each frame individually. Think the film blotches. Too much faster, and most people wouldn’t see a blip of a blotch and go, “oh a film blotch”, though they might still see it and go, “huh what was that?” up to some pretty significant framerates.
Though that’s because your eyes don’t see in frames. They’re always receiving info. That’s why even non-framerate related things improve visual smoothness, like how some monitors/technologies (sorry I forgot which ones specify it!) will flash the backlight for the frame instead of keeping it on. Then your eyes don’t get all the muddy colored photons from when the screen was actively changing pixels. It can massively reduce artifacts and makes 120hz feel like 240hz, even though at those speeds, you cannot “see” each frame.
TL;DR: It’s the Avatar kind of “see”, not the literal kind of “see”.
LodeMike@lemmy.today 2 days ago
RaccoonBall@lemmy.ca 1 day ago
Same. Going to the theatre has always been kind of rough for that reason.
On a smaller tv its less annoying, but I still wish we could do away with 24p
marcos@lemmy.world 2 days ago
Hum… The minimum to make it feel like motion is something closer to 15 Hz.
I have no idea where people pulled the 24 Hz number from, but 60 Hz is clearly enough for everybody. Anyway, if you go inserting random noise you can disrupt the people’s perception at any frequency, the noise just needs enough total energy.
DaleGribble88@programming.dev 2 days ago
24 fps was the capture rate of old film cameras. The reason for that is because of how sound was stored on the edge of celluloid tape. Because of how the sound waves where imprinted on the tape, the max fidelity was at sample rate of at most 10,000 Hz per 18inches of tape. So, 18 inches of tape has to move through the projector and sound head every second.
Consider a 35mm film reel which was popular at the same time. On a 35mm reel, the height of a single frame is about 19mm. So we have 18 inches (457mm) going across the projector screen, which shows a new frame of film every 19mm. That tells us the frame rate: 457/19 = 24.
And that is why films run at 24 fps. Because it was the natural result of technical constraints when sound started being added to film. This is why older silent movies could use lower frame rates. Super 8 cameras recorded at 18fps because they could get away with it, but once Sound Super 8 hit the scene, it got brought back up to 24fps for much the same reasoning as the 1930s had with 35mm film.
Thunderbird4@lemmy.world 2 days ago
But film projectors, even in the late silent era, didn’t just flash the image once per frame. They had two or three bladed shutters so the image on screen would actually flash 48 to 72 times per second even though the film frame was only advancing 24 times per second. The whole point of the extra shutter flashes was to push the flickering of the light on screen above the flicker fusion threshold of your eye where you are able to differentiate between individual flashes of light. For most people, it’s about 50-90 Hz in the center of their field of vision.
Strangely enough, the flicker fusion threshold in the center of your vision is lower than at the edges, which is why you can usually notice the blinking of LED headlights more easily in your peripheral vision than when you’re looking straight at them.
DaleGribble88@programming.dev 2 days ago
Hmm… I’m detecting that we may be operating with different definitions - made no more clear by the fact that you are talking about projectors while I’m answering a question about cameras. To me, a frame is a single still image on a reel of film.
I think I see your point that a projector would insert more black transitions from on frame to the next so that the black transition from one frame to the next isn’t as noticeable. However, I don’t see the connection to original discussion about frames per second or where the film industry standard of 24fps came from.
gnutrino@programming.dev 2 days ago
You should try VR sometime…
marcos@lemmy.world 2 days ago
VR has a lag problem, not a frame rate problem.
Basically every argument against low frame rate displays you can find have the form of “we linked responsibility to the display frame rate and now we have a lag problem! low frame hates are the Devil!”
Snazz@lemmy.world 2 days ago
You might be talking about the same thing.
If you are talking about how much time it takes to render an image, that is frame lag. It’s the hard limiting factor of frame rate. A computer can’t display images faster than it can draw them.
If you are talking about time between a change in the world state, and the display showing that change, that is latency. Latency is affected by a few factors including frame rate. A frame rate of 24 adds an average latency of 21ms, and a frame rate of 60 adds an average latency of 8ms. This is because as frames linger for longer, they become increasingly outdated from the actual world state.
kayohtie@pawb.social 2 days ago
When it’s low enough, for VR, they’re effectively the same problem.
FatVegan@leminal.space 1 day ago
Whenever i upgraded monitors, i was always disappointed, because i expected something amazing. I’m now on 200hz. But stepping down, oh boy you can tell. Maybe not from 20 to 165, but back to 60, from 60 to 30 becomes unplayable
marcos@lemmy.world 1 day ago
Yes, because games usually synchronize with the monitor clock, and need several clock cycles to update their world model.