120hz and movies question

[tomanystraydogs]

I understand the benefits of 120hz lcd and motion.

But what if a movie intentionally is shot to look 'jerky'?

I'm thinking of the arena fight scene in Gladiator. Would 120hz make this look 'smooth' and thus not like the director intended?

Anyone tried it?

tia

[greenland]

Have you seen this?

http://www.avsforum.com/avs-vb/showt...8#post11688788

[tomanystraydogs]

I heard about it today, but just saw what you linked to and YIKES!

What I was asking about in my original post was, if 120hz is creating a new frame in between other frames, wouldn't it ruin the effect of a movie like Gladiator where they intentionally take frames out?

[borf]

That pic is an artifact, not what 120hz is supposed to look like. Those artifacts will decrease with better processing.

So is the action is not being displayed as intended? I've come around to thinking probably so but;


It solves multiple problems (flicker, judder, blur and others)
I believe it's something directors can learn how to work with and use to their advantage. It will open up creative avenues in cinematography not avaliable before, and reduce the need to cover up low framerates with additional artifacts.
It's something people will get used to, after which they won't want to go back.
Your eyes will love you.
It's the future

[Enigma]

It only solves judder if it eliminates 3:2 pulldown, correct? Aren't all existing implementations still using 3:2, then doubling, inserting black frames, interpolating, etc to get to 120? When will we see true 5:5 pulldown (probably not the correct term) for 24 hz input?

[borf]

You're right that 3:2 pulldown is still incorperated (unconfirmed) but raising the temporal framerate to 120hz will still do much to cut the judder down (should be 1/2). Believe me you don't want 5:5 pulldown because repeating frames also produces judder. You're not going to see it on any TV's unless it's to re-create the "film judder" feel.

[noears]

Originally Posted by borf

You're right that 3:2 pulldown is still incorperated (unconfirmed) but raising the temporal framerate to 120hz will still do much to cut the judder down (should be 1/2). Believe me you don't want 5:5 pulldown because repeating frames also produces judder. You're not going to see it on any TV's unless it's to re-create the "film judder" feel.

Whaaaa?

3:2 pull-down already repeats frames and with different durations causing judder. 5:5 pull-down can only be an improvement since it eliminates the uneven pull-down.

[SMac770]

120Hz should show all formats exactly as they were intended. 24Hz film material should be shown with each original frame displayed exactly 1/24 of a second. No different. At 120Hz, each frame is displayed 5 cycles, then the next frame. Absolutely no point to "fabricating" any material whatsoever. If 120Hz displays are doing anything more than showing all material, 24Hz x5 / 30Hz x4 / 60Hz x2, with their exact original frames and cadence, then I would say they totally screwed the entire point of 120Hz up.

The one exception is 30Hz interlaced material, where progressive can never display as it was originally captured as there is never an entire frame of single-point-in-time original material. But I've not seen much problem with deinterlacing of such material on my DLP, so cool. But screwing with originally progressive film material? Displaying anything but only the original frames should not be tolerated.

[borf]

Originally Posted by noears

Whaaaa?

3:2 pull-down already repeats frames and with different durations causing judder. 5:5 pull-down can only be an improvement since it eliminates the uneven pull-down.

It is an improvement just like you said. My point was just that 5:5 doesn't eliminate judder like many are saying.

Originally Posted by SMac770

they totally screwed the entire point of 120Hz up. Displaying anything but only the original frames should not be tolerated.

I respect your preference for the original film content but the original purpose of 120hz is to remove LCD blur and judder. I think you are overlooking these intended advantages. 5:5 which duplicates film judder is obviously couterproductive to this (which is why it's not being incorperated).

[Nmlobo]

I've read that the 120Hz functionality can be turned off and that many do that while watching movies. They leave it on for all other viewing. Can anyone verify this?

[tower101]

Originally Posted by borf

It is an improvement just like you said. My point was just that 5:5 doesn't eliminate judder like many are saying.



I respect your preference for the original film content but the original purpose of 120hz is to remove LCD blur and judder. I think you are overlooking these intended advantages. 5:5 which duplicates film judder is obviously couterproductive to this (which is why it's not being incorperated).

Yes 5:5 can remove judder for film based material (anything shot in 24fps)

Judder and blur are two different problems, but both can benefit by 120.

How would 5:5 duplicate film judder

Judder is caused be using 3:2 pulldown by multiplying the frames unevenly, if you use a 5:5 the frames are multiplied evenly that eliminates judder.

The original purpose of 120 on LCD has nothing to do with judder only blur

Reread SMac770 post

[tower101]

Originally Posted by Nmlobo

I've read that the 120Hz functionality can be turned off and that many do that while watching movies. They leave it on for all other viewing. Can anyone verify this?

Yes, why because they are still using 3:2 pulldown getting to 60 then doubling that to 120 making judder worse.

[tower101]

Interpolation is very difficult and if not done right you get what Greenland linked in post #2

[tower101]

Originally Posted by OreoJoe

Many do not know the context surrounding that picture. This is a single frame taken from a 30fps camcorder film made by photographing the TV screen. It is meant to show the triple football effect when the cameraman pans to follow the ball. When the ball crosses something of high contrast in the background, the processor makes errors in the resultant frames. The football artifact is from the processor, the other artifacts are from the camcorder.

The quadruple field lines and players are from quadruple exposures in the camcorder. The lines and players move, but the ball remains still. The ball also has a quadruple exposure, but there is no relative movement because the camera follows the ball. 120fps/30fps=4 exposures.

Thanks for the detailed explanation of the pic, the artifact of the football is indeed because of the poor job the processor is doing with interloping. Many are having this problem like I said its not easy to do.

[borf]

Originally Posted by tower101

Yes 5:5 can remove judder for film based material (anything shot in 24fps)

I understand why you would say that. It's being spread around the internet even by "credible" sources.

Originally Posted by tower101

Judder and blur are two different problems, but both can benefit by 120.

They are both caused by repeating frames (hence a common solution). Repeat them briefly and you see judder. Repeat them continuously (like an LCD) you see more blur than judder.

Originally Posted by tower101

How would 5:5 duplicate film judder

By repeating frames like film projectors do.

Originally Posted by tower101

Judder is caused be using 3:2 pulldown by multiplying the frames unevenly, if you use a 5:5 the frames are multiplied evenly that eliminates judder.

3:2 judder is gone but not "repeat frame" judder.

Originally Posted by tower101

The original purpose of 120 on LCD has nothing to do with judder only blur

Blur is often stated as the purpose of 120hz since LCDs don't judder as much as other displays. Their problem is blur. No as i said they have a common cause so fixing one fixes the other. If you still believe 5:5 doesn't judder view the movie clips here:

[tower101]

So you are saying that judder is not caused be 2:3 pulldown and that the 2:3 pulldown does not repeat the frames unevenly LOL.

Blur has NOTHERING to do with cadence if it did you would see it on a crt but you don't, you do see judder though.

And you say that film projectors use a 5:5?

And your "prof" is a Hitachi add?

So let me ask you this sense hopeful we can agree that almost all film is at 24fps how do you get to 60 without unevenly repeating frames?

By the way no projector that I have heard of uses 5:5 they do a double flash some newer ones can do a tripple flash.

All the slow panning shots I have seen in the movie theater are nice and smooth most be a bummer for you seeing judder in the movie theater.

I am guessing you have never seen a TV that can properly do 48 (2:2) 72 (3:3) with film, if you had you would be amazed at how good it looks.

[hoodlum]

120hz will not give you all of the intended resolution with movement.

"The result, three distinct groups emerged from this test of the twenty 1080p displays. All displays in the top group were plasma HDTVs. They all had a static resolution of 1080 lines and a measured motion resolution of 830-880 lines, depending on the specific display. The next group consisted of microdisplay rear projectors, static measured 1050-1080 (depending on the display) while motion resolution ranged of 610-780 lines. The bottom group were all the LCD flat panels, with a static resolution of 400 (one panel) to 1080 lines and motion rez coming in at 360 lines (one set tested) to 600 lines. Three of the LCDs tested were 120 Hz models (one was the Sony KDL-46XBR4 reviewed here), all 120 Hz models had 600 lines of motion resolution."

http://www.avsforum.com/avs-vb/showthread.php?t=913792

[borf]

Originally Posted by tower101

So you are saying that judder is not caused be 2:3 pulldown and that the 2:3 pulldown does not repeat the frames unevenly LOL.

Blur has NOTHERING to do with cadence if it did you would see it on a crt but you don't, you do see judder though.

And you say that film projectors use a 5:5?

And your "prof" is a Hitachi add?

So let me ask you this sense hopeful we can agree that almost all film is at 24fps how do you get to 60 without unevenly repeating frames?

By the way no projector that I have heard of uses 5:5 they do a double flash some newer ones can do a tripple flash.

All the slow panning shots I have seen in the movie theater are nice and smooth most be a bummer for you seeing judder in the movie theater.

I am guessing you have never seen a TV that can properly do 48 (2:2) 72 (3:3) with film, if you had you would be amazed at how good it looks.

I must have explained the last post very badly or you didn't even read it because i said nothing above.
Anyhow since you say you don't see judder, i'll not ruin it for you.

[borf]

Originally Posted by hoodlum

"all 120 Hz models had 600 lines of motion resolution."

I'm betting the sammy 71 was not one of those. Phillips, Sony, Toshiba, Sharp - could be those 4.

[tower101]

Originally Posted by borf

I must have explained the last post very badly or you didn't even read it because i said nothing above.
Anyhow since you say you don't see judder, i'll not ruin it for you.

OK I do not have the time to go though every wrong point you made but I do suggest that you do some research.

Give you one example (the first one you made)

"Originally Posted by tower101
Yes 5:5 can remove judder for film based material (anything shot in 24fps)

I understand why you would say that. It's being spread around the Internet even by "credible" sources."

So you are saying that judder can not be removed by evenly repeating the frames. You either do not know what judder is or are just repeating some strange thing you read on the Internet.

[AlenK]

Originally Posted by tower101

OK I do not have the time to go though every wrong point you made but I do suggest that you do some research.

Wow, are you psychic? That's _exactly_ the advice I was going to give to you! Borf is essentially correct. The main source of judder in a film, whether you watch it on film or a video transfer of same, is caused by the simple repetition of frames. The explanation is right there in the thread he referenced (you didn't bother to read it, did you?). Telecine conversion from 24 fps to 60 fps (whether feilds or frames) is a _secondary_ effect. It makes the judder you're accustomed to seeing more noticeable because it makes it uneven.

To be fair, some people just don't see film judder much for whatever reason (the workings of the human brain are still largely mysterious) and only notice it when telecine makes it uneven. To those of us who do see it, however, there isn't much visual difference between 24 fps converted unevenly to 60 fps vs. converted evenly to, say, 72, 96 or 120 fps (by frame repitition). They both look bad.

[xrox]

Borf is correct,

Just think of it in terms of time. 24Hz film displays each frame for 42ms. That extended display time can be percieved as a pause and thus produce a characteristic judder called the "film look". Now look at the display times for all the cadence+refresh combinations:

60Hz (3:2) - 50ms first frame : 33ms second frame (uneven display time)

- this makes the judder much more obvious
- the solution is to even out the cadence to get back the original "film look"

72Hz (3:3) - 42ms
120Hz (5:5) - 42ms

- a better solution is to either source more frames to match the refresh or calculate more frames to match the refresh
- then you would get much smoother motion without any percievable judder

60Hz (1:1) - 17ms
120Hz (1:1) - 8ms

[tower101]

Originally Posted by xrox

Borf is correct,

Just think of it in terms of time. 24Hz film displays each frame for 42ms. That extended display time can be percieved as a pause and thus produce a characteristic judder called the "film look". Now look at the display times for all the cadence+refresh combinations:

60Hz (3:2) - 50ms first frame : 33ms second frame (uneven display time)

- this makes the judder much more obvious
- the solution is to even out the cadence to get back the original "film look"

72Hz (3:3) - 42ms
120Hz (5:5) - 42ms

- a better solution is to either source more frames to match the refresh or calculate more frames to match the refresh
- then you would get much smoother motion without any percievable judder

60Hz (1:1) - 17ms
120Hz (1:1) - 8ms

xrox

I agree with everything you are said except the first part

Go back and read post #6

"Believe me you don't want 5:5 pulldown because repeating frames also produces judder"

Guess he never saw true 24fps as the image-black-image-black-image-black.... is very hard to watch, although it will have no judder LOL

Does any one really believe that 2:2, 3:3, 4:4, 5:5 or 10000:10000 would not look better then 3:2? If you don't I will invite you over so you can see for yourself. Planet Earth looks way smoother doing 2:2 then 2:3.

Telecine judder is way more of a problem then "film judder" and really the only two ways to get rid of it that I know is to do a 1:1 like you said but the broadcasters and movie industry where to buy all new equipment (not likely) or if someone can develop an interloper that works and does not cost 10k.

Will that happen I hope so but so far the attempts to do so have not yielded very good results.

Any way I am done with this I truly hope Borf enjoys his 60Hz Hitachi, if it works for him then I say that's all that matters.

[AlenK]

Originally Posted by tower101

Does any one really believe that 2:2, 3:3, 4:4, 5:5 or 10000:10000 would not look better then 3:2? If you don't I will invite you over so you can see for yourself. Planet Earth looks way smoother doing 2:2 then 2:3.

It looks way smoother to _you_, but it doesn't look way smoother to everyone. You'll just have to take our word for that. Regarding 1:1, go watch a movie on a DLP Cinema projector in a theatre. You'll be witnessing a 24 fps refresh rate. I can't say what _you_ will see, but _I_ still see judder.

[xrox]

Originally Posted by tower101

xrox

I agree with everything you are said except the first part

Go back and read post #6

"Believe me you don't want 5:5 pulldown because repeating frames also produces judder"

Guess he never saw true 24fps as the image-black-image-black-image-black.... is very hard to watch, although it will have no judder LOL

Does any one really believe that 2:2, 3:3, 4:4, 5:5 or 10000:10000 would not look better then 3:2? If you don't I will invite you over so you can see for yourself. Planet Earth looks way smoother doing 2:2 then 2:3.

Telecine judder is way more of a problem then "film judder" and really the only two ways to get rid of it that I know is to do a 1:1 like you said but the broadcasters and movie industry where to buy all new equipment (not likely) or if someone can develop an interloper that works and does not cost 10k.

Will that happen I hope so but so far the attempts to do so have not yielded very good results.

Any way I am done with this I truly hope Borf enjoys his 60Hz Hitachi, if it works for him then I say that's all that matters.

Ahh, I think I understand where the misunderstanding is. If so then nobody is wrong, both of you are right.

The argument is what produces more judder 5:5 or 3:2(again look at the timings):

1 - 120Hz(5:5) 42ms even cadence
2 - 60Hz(3:2) 50ms:33ms uneven cadence

The answer is obviously 2!!!! Not only is the cadence uneven which is significantly more noticeable than long frame times, but the first frame is displayed for even longer than 42ms making it even worse.

-So yes, using 5:5 should look much smoother than 3:2 (this should be obvious)
-But, using 5:5 does not eliminate judder (it only reduces it to the original "film look") there is still judder present and the only way to reduce it further is to reduce the display time below 42ms.

So everyone is right

[tower101]

Originally Posted by xrox

Ahh, I think I understand where the misunderstanding is. If so then nobody is wrong, both of you are right.

The argument is what produces more judder 5:5 or 3:2(again look at the timings):

1 - 120Hz(5:5) 42ms even cadence
2 - 60Hz(3:2) 50ms:33ms uneven cadence

The answer is obviously 2!!!! Not only is the cadence uneven which is significantly more noticeable than long frame times, but the first frame is displayed for even longer than 42ms making it even worse.

-So yes, using 5:5 should look much smoother than 3:2 (this should be obvious)
-But, using 5:5 does not eliminate judder (it only reduces it to the original "film look") there is still judder present and the only way to reduce it further is to reduce the display time below 42ms.

So everyone is right

[notreally]

I'm not an engineer and am not proficient in this modern math, but how in the world do you take 5 fields of 60 and make them equal 5 frames of 24? Help, I'm lost.

[notreally]

Whoops, at my advanced age I'm also plagued by brain lock. 24 frames repeated 5 times equals 120 is that going to work? Something is missing.

[RobinPanties]

Everyone who said 5:5 is better than 3:2 is correct. It is mathematically right.
There's no "well YOU can't see it" about it. It does look better. What DOESN'T look good about it, is that it's shot in a low framerate to start. Even with the modest improvement of NOT altering the original framerate, it's still only 24 or 30 fps shite. How many PC gamers are there out there that accept playing games @ 24-30 fps? ZERO
It's 60 fps or bust. Most hardcore users only accept 100+ fps as far as benchmarking.
The reason is, GENERALLY SPEAKING, the human eye has a refresh rate of 24 fps, ON AVERAGE. So, it's natural that 24 fps material should look great to us right? no, not right. The reason is, it won't guarantee that the re-displayed frames will "sync" with our eyes. Sure, in nature, we VIEW 24 fps (on average) and it's true that "the hand is quicker than the eye" (noobs, wave your hand in front of your face, it's blurry!) BUT, your EYES are creating the blur effect (INTERPOLATING) due do the inability to process the speed at which your hand is moving. THUS, your eyes are still processing UNBLURRED images. Low framerate computer games are low framerate, but not blurred, like low framerate video. Hence, they look more "choppy". Even at 30 fps, games look choppy to me. 60 fps looks pretty nice, and 100+ looks amazing. Why? Because our eyes can tell a difference, even though they can't see it. It's how our brains interpolate the missing frames. However, in the case of recorded material, the camera is recording at 24/30 fps and then our eyes are processing frames that are already blurred. Add in 3:2 pulldown for 30hz displays, poor black-to-white performance in materials used to make displays, and my least favorite is the way movie theater projectors flicker the entire high wattage bulb, and you're looking at some poor quality video (I used to work as a theater projectionist for about 3 years in high school/college) My 1080p Panasonic PT-AE1000u playing 720p WMVHD from xbox live upscaled to 1080p looks better than when I go to the movie theater. But, it still suffers in fast motion due to two reasons, 24/30 fps and LCD black-to-white (or grey-to grey, if you prefer) performance in pixel lighting. Plus, not everyone can see at the same rate, hence why some can see things that others cannot. It's undeniable that some people have "faster" eyes than others. The football image, more easily explained, is displayed 5 times in the same amount of time it took the camcorder to record one time. It's a very similar to a "time exposure" photograph of a city street with cars and streaking taillights. Which is exactly what it is, time exposed. In the case of the photo, the television "chip" is interpolating. Since the image is moving side-to-side, and the display shows the same frame 5 times per normal 1frame displaying, it is simply moving the frame 5 times to simulate a higher framerate. It happens so fast, you won't see it in motion, but a camera can "catch" it. This is false, because the camera is not recording as fast and is capturing a time exposure. The interpolation effects of these displays may look more impressive than just showing the same frame in the same position 5 times in a row, but may also occasionally have an undesired effect. However, if you have a blu-ray player and a disc that preserves 24fps, it will display 24 frames 120 times in a second. effectively showing 1 frame every 1/5th of a second and showing the same frame for 5/120 seconds. This will not look bad. Only would previously mentioned 24 fps converted to 30hz (3:2) would not look good. The best thing of all about 120hz is that it will encourage the people creating the material/broacasts to shoot for higher framerates. That's what we REALLY want, is higher framerate material, not a high framerate display showing low framerate content. But, the chicken (display) will have to come before the egg (content) in this case. Manufacturers simply do not go out of their way to create content for technology that isn't there. Just as many low budget TV and "film" companies don't record digital material in 4k resolution because they know it's going to be displayed @ 1080 at best, people making movies and recording sporting events don't record at 120 fps and then downconvert it to send it to us, nor do they record at 120 fps and send it to us and let our boxes/displays downconvert it. The biggest reason? Bandwidth. It CURRENTLY isn't even a reality that we receive 1080p content via cable/satellite at current framerates due to lack of bandwidth. Why would they try to throw in 5x the frames? But, at least by buying a 120hz display, you're getting a display that is capable of refreshing at that rate and are "future-proofing" yourself.

[RobinPanties]

Everyone who said 5:5 is better than 3:2 is correct. It is mathematically right.
There's no "well YOU can't see it" about it. It does look better. What DOESN'T look good about it, is that it's shot in a low framerate to start. Even with the modest improvement of NOT altering the original framerate, it's still only 24 or 30 fps shite. How many PC gamers are there out there that accept playing games @ 24-30 fps? ZERO
It's 60 fps or bust. Most hardcore users only accept 100+ fps as far as benchmarking.
The reason is, GENERALLY SPEAKING, the human eye has a refresh rate of 24 fps, ON AVERAGE. So, it's natural that 24 fps material should look great to us right? no, not right. The reason is, it won't guarantee that the re-displayed frames will "sync" with our eyes. Sure, in nature, we VIEW 24 fps (on average) and it's true that "the hand is quicker than the eye" (noobs, wave your hand in front of your face, it's blurry!) BUT, your EYES are creating the blur effect (INTERPOLATING) due do the inability to process the speed at which your hand is moving. THUS, your eyes are still processing UNBLURRED images. Low framerate computer games are low framerate, but not blurred, like low framerate video. Hence, they look more "choppy". Even at 30 fps, games look choppy to me. 60 fps looks pretty nice, and 100+ looks amazing. Why? Because our eyes can tell a difference, even though they can't see it. It's how our brains interpolate the missing frames. However, in the case of recorded material, the camera is recording at 24/30 fps and then our eyes are processing frames that are already blurred. Add in 3:2 pulldown for 30hz displays, poor black-to-white performance in materials used to make displays, and my least favorite is the way movie theater projectors flicker the entire high wattage bulb, and you're looking at some poor quality video (I used to work as a theater projectionist for about 3 years in high school/college) My 1080p Panasonic PT-AE1000u playing 720p WMVHD from xbox live upscaled to 1080p looks better than when I go to the movie theater. But, it still suffers in fast motion due to two reasons, 24/30 fps and LCD black-to-white (or grey-to grey, if you prefer) performance in pixel lighting. Plus, not everyone can see at the same rate, hence why some can see things that others cannot. It's undeniable that some people have "faster" eyes than others. The football image, more easily explained, is displayed 5 times in the same amount of time it took the camcorder to record one time. It's a very similar to a "time exposure" photograph of a city street with cars and streaking taillights. Which is exactly what it is, time exposed. In the case of the photo, the television "chip" is interpolating. Since the image is moving side-to-side, and the display shows the same frame 5 times per normal 1frame displaying, it is simply moving the frame 5 times to simulate a higher framerate. It happens so fast, you won't see it in motion, but a camera can "catch" it. This is false, because the camera is not recording as fast and is capturing a time exposure. The interpolation effects of these displays may look more impressive than just showing the same frame in the same position 5 times in a row, but may also occasionally have an undesired effect. However, if you have a blu-ray player and a disc that preserves 24fps, it will display 24 frames 120 times in a second. effectively showing 1 frame every 1/5th of a second and showing the same frame for 5/120 seconds. This will not look bad. Only would previously mentioned 24 fps converted to 30hz (3:2) would not look good. The best thing of all about 120hz is that it will encourage the people creating the material/broacasts to shoot for higher framerates. That's what we REALLY want, is higher framerate material, not a high framerate display showing low framerate content. But, the chicken (display) will have to come before the egg (content) in this case. Manufacturers simply do not go out of their way to create content for technology that isn't there. Just as many low budget TV and "film" companies don't record digital material in 4k resolution because they know it's going to be displayed @ 1080 at best, people making movies and recording sporting events don't record at 120 fps and then downconvert it to send it to us, nor do they record at 120 fps and send it to us and let our boxes/displays downconvert it. The biggest reason? Bandwidth. It CURRENTLY isn't even a reality that we receive 1080p content via cable/satellite at current framerates due to lack of bandwidth. Why would they try to throw in 5x the frames? But, at least by buying a 120hz display, you're getting a display that is capable of refreshing at that rate and are "future-proofing" yourself (as much as I hate to use that phrase referring to anything technology related)