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Why movies look weird at 48fps, and games are better at 60fps

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Re: Why movies look weird at 48fps, and games are better at 60fps

#31

Post by elinchrome »

blakecaldwell wrote: post #28
sray wrote: post #25

I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…

Not sure about how movies are filmed, but you don't have to shoot video frames at 1/FPS. That's just the slowest you can shoot. If you're shooting in broad daylight, each frame could be as quick as 1/8000, for example. Shooting at the slowest shutter speed possible should make the most fluid video.

Worth noting that directors use high speed film to portray a feeling of confusion. The lack of motion blur gives that sense to the scene. E.g. the opening scene of Saving Private Ryan uses this effect.

Re: Why movies look weird at 48fps, and games are better at 60fps

#32

Post by wmeredith »

baby wrote: post #24

I personally love HFR and have went out of my ways to watch the three The Hobbits in HFR (I traveled to Paris, the only place in France where they have it in HFR). When people complain about 48fps being weird I just feel like they're just not used to it. It does look weird but after 20 minutes it looks amazing. I'm personally tired of not understanding anything in action movies that uses 24fps. It is kind of a luxury…

You're trying make an opinion a fact. "Better" has always been subjective when it comes to the senses, and I suspect it always will be. See the whole ridiculous audiophile cottage industry that can sell people $900 wooden volume knobs for their hi-if systems.

Re: Why movies look weird at 48fps, and games are better at 60fps

#33

Post by samatman »

sray wrote: post #25

I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…

The corollary is that it should be possible to produce a movie-like quality in games, by over-framing and compositing a blur between frames. The result would have actual motion blur and update at say 30 fps, but without the jerkiness we normally associate with that frame rate.

Re: Why movies look weird at 48fps, and games are better at 60fps

#34

Post by afterburner »

TillE wrote: post #16
AndrewDucker wrote: post #12

So, basically, at 24FPS things are blurry enough that you can't see the fine details, which means that special effects and costumes look realistic. Increase the frequency to 48FPS and the blur goes away, meaning that we can see the fine detail, and suddenly sets look like sets, costumes look like costumes, and CGI looks like a computer game.

To be fair, CGI creatures look like a computer game regardless. A very pretty computer game, but still. Sometimes it seems like people want to believe that CGI is a whole lot better than it actually is. People raved about Gollum in the LOTR films, but go back and look at it. Even at 24fps, it's not great. It certainly doesn't look real.

Could that be due to the brightness difference between seeing it in the theatre and watching it on your TV? TVs tend to be set brighter.

Re: Why movies look weird at 48fps, and games are better at 60fps

#35

Post by simias »

sray wrote: post #25

I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…

That's not entirely accurate. It's true that a camera will capture the image during a certain interval of time instead of a definite point in time (obviously) but the length of that exposition time is not necessarily connected to the framerate.

For instance if you have a digital camera where you can select the framerate (pretty common these days) and if the exposition time was simply the frame period, it would mean that the image at 30fps would be exposed twice as long as 60fps and the resulting picture would look very differently.

Of course you can mitigate that by changing the aperture and other parameters but in my experience in practice you can select the exposition time and framerate independently on digital cameras. With very sensitive sensor and/or good lighting you can achieve very small exposition times, much smaller than the frame period. If you're filming something that moves and unless you want to be blurry on purpose you probably want to reduce the exposition time as much as possible in order to have a clean image, just like in the video games.

Re: Why movies look weird at 48fps, and games are better at 60fps

#36

Post by sp332 »

sray wrote: post #25

I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…

Most movies use a 180-degree shutter angle, which means the shutter is open half the time. http://www.red.com/learn/red-101/shutter-angle-tutorial So you get motion blur for half the frame time, and no light on the film for the other half of the time. The Hobbit movies (at least the first one) used a 270-degree shutter angle, so even at half the frame time, they got 3/4 as much motion blur in each frame as a normal movie. That might contribute to the odd feeling viewers had. http://www.fxguide.com/featured/the-hobbit-weta/

Re: Why movies look weird at 48fps, and games are better at 60fps

#37

Post by shiven »

Retra wrote: post #30
sray wrote: post #25

I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…

I always use this fact as a kind of analogue to explain position-momentum uncertainty in physics. From a blurry photo of an object, you can easily measure the speed, but the position is uncertain due to the blur. From a very crisp photo, you can tell exactly where it is, but you can't tell how fast it is moving because it is a still photo. It's a good way to start building an intuition about state dependencies.

Welcome to Heisenberg's uncertainty principle[0] in the macroscopic world!

[0] http://en.m.wikipedia.org/wiki/Uncertainty_principle

Re: Why movies look weird at 48fps, and games are better at 60fps

#38

Post by teamonkey »

samatman wrote: post #33
sray wrote: post #25

I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…

The corollary is that it should be possible to produce a movie-like quality in games, by over-framing and compositing a blur between frames. The result would have actual motion blur and update at say 30 fps, but without the jerkiness we normally associate with that frame rate.

Each game frame is a snapshot taken with an infinitely small shutter duration but displayed for 1/30s or 1/60s (vs one movie frame, which has a shutter duration of, e.g. 1/48s and displayed for 1/24s).

So over-framing game frames will not produce motion blur, it'll simply merge two still images together. You need to simulate motion blur (usually as a post-process). This of course takes more time to render, potentially lengthening the frame times.

Re: Why movies look weird at 48fps, and games are better at 60fps

#39

Post by minthd »

baby wrote: post #24

I personally love HFR and have went out of my ways to watch the three The Hobbits in HFR (I traveled to Paris, the only place in France where they have it in HFR). When people complain about 48fps being weird I just feel like they're just not used to it. It does look weird but after 20 minutes it looks amazing. I'm personally tired of not understanding anything in action movies that uses 24fps. It is kind of a luxury…

Have you(anybody else here) tried interpolation ? What's your opinion of it ?

Re: Why movies look weird at 48fps, and games are better at 60fps

#40

Post by agumonkey »

sray wrote: post #25

I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…

Game renderers do sample time too, for per-object motion blur[1] and sometimes full-scene blur or AA. To push the idea further, research has been done around 'frameless' renderers, where you never render a complete frame but sample ~randomly at successive times and accumulate into the frame(sic)buffer. At low resolution it feels weird but very natural, computed persistence of vision : https://www.youtube.com/watch?v=ycSpSSt-yVs . I love how even at low res, you get valuable perception.

[1] some renderers even take advantage of that to increase performance since you get a more human oriented feel by rendering less precisely.

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