The Big Picture: Frame Rate

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BiscuitTrouser

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Aardvaarkman said:
Eyes don't have a frame rate, because they don't use frames. Where are you getting the 15fps figure from? It sounds like quackery to me.
Actually they technically do. There is only a maximum number of times per second your optic nerve can transmit an impulse to receive an image. If you show an image for less than this time you dont even see it. As long as the recording is above a certain threshhold the motion looks fluid. Anything far less and you start seeing jerky motion. There is no maximum limit to your eyes FPS in terms of media because it will look more fluid up to a point. There is most certainly a minimum value though, which IS about 15-24 above which motion looks fluid. The maximum FPS of your eyes is predicted to be around 200 (pilots can see and remember an image flashed for 1/220th of a second max). But thats totally unnecessary to be honest. The minimum value is all that is necessary for smooth motion since your brain fills in the rest. The brain cuts a LOT of corners to make reality easier to distinguish and understand. Motion is one of them. Our max FPS doesnt have a huge effect on how we see motion since our brain will fill in the gaps after 24 FPS anyway.
 

Pyrian

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Aardvaarkman said:
If the film is moving faster than your eyes/brain can perceive, then you will perceive that as "blur," just as you would with real-life objects moving faster than you can perceive in detail.
Right on. Here's the interesting thing: the eye can perceive motion at very high "frame rate", or rather it takes a very high frame rate to deceive the eye into seeing motion where there is none. (Even attempting to assign a number may be inappropriate, since for any object you can perceive at all, the ratio between the size of the moving object and the distance it moves per frame is more relevant than the speed per se, although I think you could find an upper limit where any object you can perceive moving is adequately represented, that upper limit would be very high.) 48FPS should need half as much motion blur as 24FPS, but it still needs motion blur IMO. Motion blur at 24FPS tends to be exaggerated; it "looks like film" because it is, but it doesn't look real, at least not to me. I haven't seen The Hobbit yet and do not know how it looks to me, nor even if they're using a frame-rate appropriate motion blur or not.

Don't believe me about motion requiring a very high frame rate for eye-blur to kick in? Try this simple test. If you have motion blur turned on for your mouse pointer, turn it off. Now move the mouse around quickly. Do you see a blur, or do see a cascade of discrete after-images? At 60FPS, you will easily see the discrete frames of the mouse being moved. The notion that the eye cannot distinguish frame rates above 15/24/60 is self-evidently nonsense, as anybody with a computer can test with a trivial exercise.

No, what the eye has difficulty with is detecting the difference between movement and well-implemented motion blur (and film can do a very fine job of simulating motion blur by the simple expedient of functioning similarly to eye itself). Proving that you can fool the eye does not prove that the eye cannot distinguish frames.
 

Rhys Davies

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Aardvaarkman said:
Rhys Davies said:
This. An exposure =/= as a still rendered image in a video game.
How is it not? The process to create it is not the same, but the end result is functionally identical. Actually, in computer-generated films (i.e Pixar, etc.) the process is also identical to that of video games.
Because as it's stated in the video, an exposure has motion blur, as each exposure lasts 1/48th of a second (or 1/96th for 48). Video games on the other hand are a completely still frame. games try to overcome this by adding their own form of motion blur, but doing this in real time just doesn't look any ware near effective as actual motion blur from an exposure.

CGI and 3D animated films add motion blur into their renders, and as they don't have to render it in real time, the motion blur is imposed correctly and subtly. pause toy story when it's in motion and you can see the motion blur clearly... it's what films look smooth at 24 but games look jumpy.
 

The_Waspman

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Milanezi said:
Hmpf... I don't care, but I wish they'd stop with the CGI. When CGI gets old it gets VERY ugly, to the point of us saying "dude, that's not how I remember it", using props and stuff though, when they're well done, those stick forever or at least get a classic stamp to them.
I wholeheartedly agree. And its not just when it gets old either. I saw this in the standard 24 fps, and I thought the majority of the cgi (like in the LOTR trilogy) was extremely unconvincing. If, as Bob says, the props, makeup and (I assume) visual effects appear more obvious in 48 fps, I can only imagine how terrible the cgi must look at that speed.

I really don't know how to explain it really. I mean, you can go all the way back to Jurassic Park, and (for the most part) the cg still stands up. Which I find surprising, because its all living creatures - which cgi has big problem with. Cgi animals and cgi people always stand out in films, and I can never really figure out why. Something about the way they move perhaps, or how their skin moves, like they don't have a skeletal system, or they entirely lack weight.

When I first heard about this 48 fps thing, I naturally turned my nose up at it with disgust. I cant claim to enjoy change that much. Not that I'm a luditte by any means, but when change is forced upon us when it is quite clearly un-needed (and for the most part doesn't work - thats right, I'm looking at YOU, 3D!) then I start to have a problem...
 

Sonic Doctor

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Zachary Amaranth said:
HDTVs can do frame rates in excess of 48.
I'm guessing that is why most everything I watch on the new HDTV that my dad got himself last Christmas, looks like I'm watching a stage theater production rather than movie/tv broadcasts.

The first thing I saw on that TV was "Christmas Vacation", and I was weirded-out by how real it looked.
 

snowfi6916

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I never understood the problem with 48 fps. What's wrong with technology advancing a little? Bob did say it's been 24 fps for quite a while now. I'd be willing to watch movies in 48 fps once they work the kinks out.
 

medv4380

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Aardvaarkman said:
Eyes don't have a frame rate, because they don't use frames. Where are you getting the 15fps figure from? It sounds like quackery to me.

That doesn't make any sense. If the film is moving faster than your eyes/brain can perceive, then you will perceive that as "blur," just as you would with real-life objects moving faster than you can perceive in detail.

If your comment was true, it would mean that film-makers have found a way to bypass human perception, and give the brain more information than it can process outside of a cinema. That would be a pretty amazing discovery, something worthy of a Nobel Prize or other distinguished science award. I'm pretty sure that's not what's happening, especially as 48fps is a pretty low speed, and well within human perception if you're not intoxicated or have vision difficulties.
We do see in frames. Here is a book for reference.
http://books.google.com/books?id=jzbUUL0xJAEC&pg=PA24#v=onepage&q&f=false
We see at about 15fps when you're talking about color. The Retina resets about ever 1/15th of a Second which is 15 frames per second. For some it's as low as 12 and others it could be a bit faster than 15.
There are a couple of notable exceptions though. Your night vision which is in Gray Scale is more sensitive. It has a faster refresh than color. It's also why good compression tech splits RGB into YUV which is Gray Scale, Red Croma, and Blue Croma. Because we're more sensitive to changes in the Gray scale we put the best compression on Gray and the loosy compression on the Croma values.

They haven't found a way to bypass human perception. They just found a way to display a fake image to the eye in a way the brain can tell that it's fake. You're also not getting more information. You're losing information on the motion of the image, and gaining clarity of an image. You've actually lost information to gain the clarity so you're not giving the brain more than it can take it. But because it's not how the brain sees it knows the image is fake. In part, this is because we evolved to pay attention to motion and motion blur more than clarity.
 

Aardvaarkman

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medv4380 said:
We do see in frames. Here is a book for reference.
http://books.google.com/books?id=jzbUUL0xJAEC&pg=PA24#v=onepage&q&f=false
We see at about 15fps when you're talking about color. The Retina resets about ever 1/15th of a Second which is 15 frames per second. For some it's as low as 12 and others it could be a bit faster than 15..
Those aren't frames. Frames are photographic stills on a film reel. The human brain doesn't process things that way. And a 12-year-old book about film restoration is not an authoritative source for information about human perception. The book you refer to doesn't even have any citations for this claim, and it is a very basic text about film equipment, not a scientific text about how humans perceive motion.
 

medv4380

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Aardvaarkman said:
medv4380 said:
We do see in frames. Here is a book for reference.
http://books.google.com/books?id=jzbUUL0xJAEC&pg=PA24#v=onepage&q&f=false
We see at about 15fps when you're talking about color. The Retina resets about ever 1/15th of a Second which is 15 frames per second. For some it's as low as 12 and others it could be a bit faster than 15..
Those aren't frames. Frames are photographic stills on a film reel. The human brain doesn't process things that way.
The Image on your Retina is no different than a frame of film, and the fact that we can see it reset gives a clear indication of the maximum rate it take images at.
 

Aardvaarkman

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medv4380 said:
The Image on your Retina is no different than a frame of film, and the fact that we can see it reset gives a clear indication of the maximum rate it take images at.
It's very different than a frame on film. A frame on film captures a narrow field with specific boundaries. The human eye has more of an uneven field with detail at the center, and more peripheral vision, which tends to be sensitive to motion.

And what's your source for the idea that we can "see it reset"? f that were the case, wouldn't it indicate that we are capable of perceiving things beyond the supposed "frame rate"?
 

Twilight_guy

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What argument do I want to pick at. Games being at 60 FPS and good while movies must be at 24 FPS to be good dispite both using the same moving picture mechanics? An argument over people saying that you need to give new tech a chance despite hating on DRM and saying it will never work? Maybe noting that people are saying that critics are using old thinking while also going on and on about nostalgic games? Oh so many excellent things to point out and then immediately get shouted at for, but I think I'll instead just leave immediately before I get blasted for having the gall to mention certain double standards in people's logic. AWAY!
 

Vinterdraken

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I saw it in 48 FPS and loved it. Sure it took a few minutes to get used to it and at first it pulled me a bit out of the movie. But once things got rolling I found it just added more and drew me in further. Really hope more movies will go 48 fps, it really does make a huge difference in my opinion.
 

Dastardly

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MovieBob said:
Frame Rate

How many frames per second does it take to anger critics?

Watch Video
The issue for me has nothing to do with the math. It has to do with the psychology.

When I'm watching something in real-life, there's a certain amount of blur to it, as my mind can only focus on one individual detail at a moment (like everyone else). When I'm focusing intently on someone's nose, let's say, the rest of the "scene" gets a slight haze to it. When something is moving, motion blur does the same thing.

And matching the "frame rate" of the human eye is a flawed idea, anyhow. See, in real life, as your eye tracks movement, you're not getting a consistent frame rate. Every time you move your eyes, your brain shuts down input from your eyes during that split second while your eyes are moving -- this is why you don't see images "drip" or "smear" from one to another. Your brain fills in the gaps and grows accustomed to the out-of-focus elements of the scene, especially during relative movement.

When watching in a very high frame rate, a lot of that blur is undermined. The result is that actually look less natural -- you become more aware that you're watching this scene from a greater distance, and that it's through someone else's eye. Basically, your brain buys the illusion better when it fills in the gaps itself (think Inception).
 

medv4380

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Aardvaarkman said:
It's very different than a frame on film. A frame on film captures a narrow field with specific boundaries. The human eye has more of an uneven field with detail at the center, and more peripheral vision, which tends to be sensitive to motion.

And what's your source for the idea that we can "see it reset"? f that were the case, wouldn't it indicate that we are capable of perceiving things beyond the supposed "frame rate"?
I've already provided one very good source for you. I'm not hunting down Biology, and Neurology text books or experiments that show the image on the human eye being upside down and resetting.

The only part of your argument about the differences that has any weight is a Field of View Argument, and if you want a fish eye lens and a concaved screen to display it on your welcome to it, but it wont change the film being used. You're also mistaking the focal length for the center of the eye. You can be looking at something with the center of the eye and it be completely blurry due to focus. Your eye has to adjust the focal length in much the same way as a camera man does. Your brain is sensitive to motion regardless of which part of the eye it's in, but we focus using the center to orchestrate stereoscopic vision using both eyes.

Being able to tell that the cones and rods reset at a given rate doesn't indicate that we're capable of seeing at a faster rate. There are tests that can make them run slower, but nothing has ever made them run faster. Even adrenaline tests using bungie jumping couldn't get the eye to send images to the brain any faster.

At 48fps we're actually displaying 3.2 fluid frames on the retina each with a gap of time between them so ~3 gaps.
At 24fps we're only showing 1.6 fluid frames on the retina with ~1 gap.
As far as the brain is concerned it only sees 1 fluid frame but one has a lot of gaps in the motion information and the other has very few gaps. Keep in mind, the only reason we didn't settle on 15fps is because of optical effects that were happening. The brain does a good job filling in the missing information but that's because it does this anyways, but the brain is lazy and doesn't like added work.

The problem is the lack of understanding of what a Fluid Frame is. Think of a single Fluid Frame as a continuous stack of still frames. The brain can extrapolate a lot of information from that single frame. In part, that is way people don't think they see as slow as 15fps, but that's because they think of a frame as a still drawing and not as a 1/15th of a second continuous exposure of information.

By going to 48fps they've made fluid frames look more like still frames. That gives you clarity, but at the sacrifice of the fluid motion. The brain actually cares more about that fluid motion than it does about the clarity of the image.

If all they wanted was clarity they should have done something with the resolution first. Getting the maximum number of dots on the screen for the average theater seat would have been a better bet, and I believe that's only an issue because of Digital and not an issue with 35mm film.
 

Sheo_Dagana

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I'm not sure if it was the new frame rate or not, but the special effects in this movie seemed worse to me than Fellowship had over a decade ago. I don't know if the frame rate was affecting that, and THAT is what critics are complaining about, or if it was because Peter Jackson is working with a much smaller budget for the Hobbit trilogy.

I readily admit to having little knowledge in this field, but it didn't matter to me because I still really enjoyed the film start to finish.
 

Yvressian

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I managed to see the movie in 48 frames, and I must admit that I didn't really like it.
On paper, a higher frame rate sounds great: more=better, and all it does is provide a higher image clarity, right?

Well, not exactly. First of all, yes, the image is stunningly clear, which is great. On the other hand, as Bob explained in the video, this is why some of the props and prosthetics in this particular movie look a bit fake. Obviously, this isn't a big problem, and even movies without so many special effects will have no problem with this.

However, my biggest complaint with the 48FPS video is that it gives movement a very "unnatural" feel. When characters move, they look ever so slightly too fast, as if the video is being unintentionally played at a higher speed, but not constantly. As a result, human movement looks a little bit too quick and jerky at times. It's hard to explain, but it kind of looks like a video-game cinematic that keeps slowing down and speeding up (like when you have a weak GPU). The result is an immersion-breaking "feel" to the movie. You do kind of get used to it if there is constant movement, but if the pace of the movie slows down and then speeds up again, you start noticing it again.

The most ironic thing is that human movement in the new 48 frame technology actually reminds me of the footage from old hand-crank cameras from the beginning of the 20th century, for example:

http://www.youtube.com/watch?v=BJNbO1Mbl2w
 

crimson5pheonix

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I saw it in 48fps and it was great. I don't know what people are talking about where it makes things looker faker than it normally would...
 

nondescript

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Eabus said:
Thanks Bob, that explanes why my roommate was going on about frame rates right before we went to see The Hobbit.
Seriously! I do music videos for fun, and some wanker posted a comment about it having "slow fps". As if 24 was now arctic slow. Next they'll say smart phones are something "my grandpa uses." Whiny entitled brats.

As far as the movie went, I didn't notice, or gave it a pass on how it looked. The only place I did a double take was Gollum looked... different. 'Course, that could have been an update on effects overall, and not the frame rate. Won't know till the extended edition DVD comes out.

WHEN DOES IT COME OUT?!?