I've been under the impression that "hz" means "frames per second." I'm not sure whether that's correct or not but people have told me that "60hz" = 60 frames per second, and "120hz" = 120 frames per second.

My question is, if blu-ray discs only have 24 frames per second on them, and tv is only broadcast at whatever it is, 30, or 60, frames, then why do 120hz displays look more fluid than 60hz displays? If blu-rays are only 24 frames per second than it stands to reason that regardless of whether or not a display is 120hz or 60hz, both displays can only play the blu-ray disc at 24 frames per second. Does the 120hz display just play each of the 24 frames per second 5 times before going to the next frame in the time that it would usually take to display one frame? And if so, how does that help the picture at all, if the frames aren't moving except for the 24 frames?

http://en.wikipedia.org/wiki/Telecine

120 is a multiple of 24 and 60, which allows both film and video to be displayed at 120hz without converting 24fps film to 60fps using 3:2 pulldown, which introduces motion stutter. Original frames are simply repeated the necessary number of times.

Mark

ok if your watching a tv show or sports mainly anything thats shot on video and not film (anything but movies) 120hz is fine since its a multiple of the 30frames per second that video is shot at but film is filmed at 24fps...(and shown that way on analog projectors at the theater) 120hz was a huge marketing gimmick (I think samsungs uses it) theres a lot out there to confuse people right now into believing one distributer has the best advantage) all 120hz does is show the same frame 4 times in a row and all 30 frames 4 times each in one second...some say this results in a brighter more solid looking picture....I say if you can really tell the difference you should think about flying jets for the military.
EDIT.....I was misinformed on this and admit there may be more real world difference good and bad than I originally thought when posting above comment.....

I've watched Reservoir Dogs on Blu-Ray at 120hz on a samsung TV and I can tell a HUGE difference. The 120hz makes everything extremely smooth. Personally I would rather have BR at 1080p/120hz rather than 24hz, but that's just me. I've watched multiple movies on 120hz TV's and it does make a huge difference. Now with that said if you go into a Best Buy or something and see all the TV's showing the same image, you won't see a mojor difference between 120hz and the other LCD TV's because the image is being multiplied through many TV's.

I've watched Reservoir Dogs on Blu-Ray at 120hz on a samsung TV and I can tell a HUGE difference. The 120hz makes everything extremely smooth. Personally I would rather have BR at 1080p/120hz rather than 24hz, but that's just me. I've watched multiple movies on 120hz TV's and it does make a huge difference. Now with that said if you go into a Best Buy or something and see all the TV's showing the same image, you won't see a mojor difference between 120hz and the other LCD TV's because the image is being multiplied through many TV's.

Something tells me that, that HUGE difference your seeing if you reffering to AMP and not the TV doing 120hz. Two different things.

I see a huge difference with 120hz and frame interpolation on. you would have to be blind to not see the difference. On 60 frame material like tv shows, its not as noticable, but for movies especially hd ones the difference is astonishing. With 4:4 pulldown, which I believe is just 96 frames being played and the exact frame no creation of a new frame like you get with FI, I see a smoother picture, but its nothing compared to FI, which adds alot more depth and speeds everything up so it looks kind of soap-opera like with some movies, so some people think it looks cheap, but it works well for many movies. Having 120hz in itself might not be as noticable, but that FI is not gimmicky, it gives the movie a whole new experience.

...all 120hz does is show the same frame 4 times in a row and all 30 frames 4 times each in one second...some say this results in a brighter more solid looking picture....I say if you can really tell the difference you should think about flying jets for the military.No, I say MOST people will notice an improvement in rates >24. This now-ancient standard for film production is a compromise of film cost vs. the natural tendency of an image to persist in the human eye. It just barely "makes it" for many people, but there are many others who naturally see the "flicker" of projected 24fps movie film (even with the shutter operating twice for each frame i.e. 48 opens/closes per film frame).

Many years ago Douglas Trumbull of '2001' fame tested a number of framerates and identified 60fps as ideal for his proposed "showscan" system. That doesn't mean of course that there aren't people for whom >60 wouldn't be an improvement...everybody's eyes/optic nerves/brains are of course totally different (and thank God for that!)!!! :p

120 hz is also to facilitate another attempt at making polarized 3d mainstream. With 120 hz, each eye can then see 60 hz, so no more flicker.
120 hz interpolation applied to none 3d imo is bs, and produces unnatural looking movement.

I seen many tech people discussing this hz thing. The higher the hz does not matter. Or it didnt as of a year ago. Dont know about today. BUt really its just more of a selling point for consumers. ohhhh....higher hz must be better...here is my $$$$$..NOW GIVE it to me!

I seen many tech people discussing this hz thing. The higher the hz does not matter. Or it didnt as of a year ago. Dont know about today. BUt really its just more of a selling point for consumers. ohhhh....higher hz must be better...here is my $$$$$..NOW GIVE it to me!

This is not necessarily true. Like others have said you do see a difference with 120hz. Watch two videos side by side one at 24hz and the other at 120hz, you'll see the difference, trust me.

This is not necessarily true. Like others have said you do see a difference with 120hz. Watch two videos side by side one at 24hz and the other at 120hz, you'll see the difference, trust me.

and that I've yet to do....what is this difference just extra bright picture?....after all we are just talking about showing the same frames a bunch of extra times a second...and maybe adding the judder from the extra frames being dropped or shown an uneven amount of times? I see a lot of "there's a difference" but no ones said what it is? To be honest I never bothered to take it serioulsy since all the serious HT buffs here were always talking about 24fps displays being the holy grail of display resolution when it comes to movies....I have a 1080p/24hz and a 48hz feed coming into my projector and I honestly dont see much different besides 1080p being a lot less sharp on my 720p display....you would thing that double the frames per second (especially from going from so few as 24 as someone said was easy to spot flicker for many to 48?.....hell even at 60hz i dont notice much of a difference....(horizontal black bar edges seem less sharp thats all?) and while maybe my nerves aren't sensitive enough I have perfect vision and can notice rainbows on dlp's if I look for them so...is this one of those things that people only notice if they've paid for it or maybe the rare few with extra ordinary nerves and optic reflexes ?(why I made the jet pilot comment earlier)
If more is better how come everyone seems to preffer 24fps (hz) over 72 frames per second which would still eliminate pulldown judder? I'm not bashing here just really trying to understand things here? or does this whole thing make such little difference that the sane home theater guys really dont care? Are we being ridiculous about all this? none of my guests can ever see a difference when I ask I just did it cause I could and didnt have to pay extra for it.

I don't notice a difference in image quality at all, I didn't know there was suppose to be one. The difference I see is that it is much smoother and things don't jitter around as much, people running are a hell of a lot more smoother (Their legs moving and such). As far as the 24hz vs 72hz goes, I don't know for sure this is just a guess and someone please correct me if i'm wrong, but I believe the reason 72 hz isn't popular is because that's only a multiple of 24hz which only applies to blu-rays (DVD as well?), where as 120hz is a multiple of 30hz, 60hz, 24hz, which is all of the popular formats used (Dish, DVD, Blu Ray, etc).

I personally haven't ever heard of anyone saying that 120hz *Looks* better because I don't believe it would since it's still the same image, I'm simply saying that if you take two videos side by side of a person swimming you'll see a difference in the way that the water is splashing up and coming back down. It makes mostly everything a lot less jaggedy (For lack of a better term).

I went to the sony style store and when I first saw 120hz I didn't like but warmed to the look. The thing that was most asked was how does this look watching live broadcast television. I have been searching for this answer for sometime and like I said in the Mits HC5500 thread people just say its great. No one just watch movies there are a lot of live broadcast shows.

Most ht enthusiasts, going for accuracy, consider applying 120 hz interpolation to video to be considered distortion. It makes things feel smoother, but in an unnatural way. Think cheesy soap opera vs. theater film movement.

I don't notice a difference in image quality at all, I didn't know there was suppose to be one. The difference I see is that it is much smoother and things don't jitter around as much, people running are a hell of a lot more smoother (Their legs moving and such). As far as the 24hz vs 72hz goes, I don't know for sure this is just a guess and someone please correct me if i'm wrong, but I believe the reason 72 hz isn't popular is because that's only a multiple of 24hz which only applies to blu-rays (DVD as well?), where as 120hz is a multiple of 30hz, 60hz, 24hz, which is all of the popular formats used (Dish, DVD, Blu Ray, etc).

I personally haven't ever heard of anyone saying that 120hz *Looks* better because I don't believe it would since it's still the same image, I'm simply saying that if you take two videos side by side of a person swimming you'll see a difference in the way that the water is splashing up and coming back down. It makes mostly everything a lot less jaggedy (For lack of a better term).
60hz and 24hz are not mutiples of each other at all....60 is a multiple of 30 which is for watching video content.....movies are mostly all done in 24fps (48,72 ect)and 120hz should be less smooth than 72 for movies because of the fact that its based off video frame rate multiple but their maybe something else to this I dont know about.

Just think though - you already have the gear in place to make use of the 3D gaming that nVidia has...well, maybe you'll want to wait until they perfect the technology a little more...
:D

Most ht enthusiasts, going for accuracy, consider applying 120 hz interpolation to video to be considered distortion. It makes things feel smoother, but in an unnatural way. Think cheesy soap opera vs. theater film movement.

this is sorta what I was wondering.....but it cant really be any faster because its still times out the same and to the audio? cheesy soap operas seem fast and sped up..not sure how just showing the same 24 or 30 frames four times a second instead of twice would make motion seem faster (theres no movement in showing the same frame multiple times in a row)....not that I dont believe it just trying to understand how that could be?

this is sorta what I was wondering.....but it cant really be any faster because its still times out the same and to the audio? cheesy soap operas seem fast and sped up..not sure how just showing the same 24 or 30 frames four times a second instead of twice would make motion seem faster (theres no movement in showing the same frame multiple times in a row)....not that I dont believe it just trying to understand how that could be?
Thats because you're confused by what others have stated. 120 hz interpolation is NOT just the same frames repeated, hence the use of the word "interpolation," which mathematically means to construct new data points using existing data.
What happens is two frames, A and B, are examined, and a new frame (or more) is derived from those two frames. These newly derived frames are frames that contain data that is between frames A and B. So in essence you're taking existing video frames, and developing and displaying new "transition" frames that make the transition from frames A and B smoother.

60hz and 24hz are not mutiples of each other at all....60 is a multiple of 30 which is for watching video content.....movies are mostly all done in 24fps (48,72 ect)and 120hz should be less smooth than 72 for movies because of the fact that its based off video frame rate multiple but their maybe something else to this I dont know about.
24 hz times 5 equals 120 hz. And 30 hz times 4 equals 120 hz. So in essence you can use a flat refresh of 120 hz and display video content normally, and avoid 3:2 pulldown (and therefore judder) with movie content.
However, the other bit of 120 hz is the frame interpolation as i mentioned in my previous post.

some say this results in a brighter more solid looking picture....I say if you can really tell the difference you should think about flying jets for the military.
Well, sign me up ;)
The differences are definitely there, though they are not always good differences.

To summarize, since my posts are a bit of a jumble:
1.) 120 hz displays can use non-interpolation methods and just repeat frames. This accomplishes:
...a.) Avoidance of judder from 3:2 pulldown with 24 fps material (movies).
...b.) Ability to also play video mastered content (30 hz) at the same refresh rate.
...c.) With no interpolation used, the repeating of frames can allow 3:2 pulldown to eb avoided, while still avoiding flicker (24 fps produces flicker).
2.) Frame interpolation can be used with displays supporting 120 hz. This is an attmept to take existing, non-120 hz material, and make it look almost as smooth by deriving new transition frames.

I personally don't mind non-interpolation 120 hz, but i don't like 120 hz interpolation applied to most material as it makes it look unnatural.

p.s. i apologize for the four posts in a row ;)

24 hz times 5 equals 120 hz. And 30 hz times 4 equals 120 hz. So in essence you can use a flat refresh of 120 hz and display video content normally, and avoid 3:2 pulldown (and therefore judder) with movie content.
However, the other bit of 120 hz is the frame interpolation as i mentioned in my previous post.

good point, I didnt even think to do the math in my head...and that makes sense with the frames being interpolated....although there got to be a lot of image processing going on there to create frames like that and still keep things sharp?

good point, I didnt even think to do the math in my head...and that makes sense with the frames being interpolated....although there got to be a lot of image processing going on there to create frames like that and still keep things sharp?
I'm not sure, is that a question? :D
And yeah, there is a lot of image processing going on to do it.

My take is that if you want to see the movie the way the director intended it to be seen at the theather or home theater, then don't screw with it, watch it with its 24fps 1080p glory, movies in cinema are not supposed to look 100% sharp as if you're looking out the window, Cinema has a different feel, thats why your home video camera cannot produce the same look a directory can after editing and postproduction. If you prefer watching your movies with quadruple duplicates of the same frame rate or with FI then you're really watching movies your way, not the director's way, and there is nothing wrong with that, its a preference.

On the other hand, FI and frame rate duplication is not a bad thing when watching HDTV broadcasts and sports (not film), but I honestly think all the pop and depth created by FI is just a gimmick, I was very close to buying an Epson 7500ub because of the FI, until I saw how it made things look like, it felt like I was watching things in real life like looking out the window, and in some cases it did feel very soap opera and wax-musuem-ish, it just did not feel natural as to the film's natural frame rate. Movies are supposed to have motion blur, thats part of the kick of a true film-like projector. I used to be all about pop, depth, and over saturated colors but since seeing the JVC RS20 in action, I am a true film afficionado! I want the film quality picture, even if it doesnt look as shiny and poppy as 4:4 or FI.

My take is that if you want to see the movie the way the director intended it to be seen at the theather or home theater, then don't screw with it, watch it with its 24fps 1080p glory, movies in cinema are not supposed to look 100% sharp as if you're looking out the window, Cinema has a different feel, thats why your home video camera cannot produce the same look a directory can after editing and postproduction. If you prefer watching your movies with quadruple duplicates of the same frame rate or with FI then you're really watching movies your way, not the director's way, and there is nothing wrong with that, its a preference.

On the other hand, FI and frame rate duplication is not a bad thing when watching HDTV broadcasts and sports (not film), but I honestly think all the pop and depth created by FI is just a gimmick, I was very close to buying an Epson 7500ub because of the FI, until I saw how it made things look like, it felt like I was watching things in real life like looking out the window, and in some cases it did feel very soap opera and wax-musuem-ish, it just did not feel natural as to the film's natural frame rate. Movies are supposed to have motion blur, thats part of the kick of a true film-like projector. I used to be all about pop, depth, and over saturated colors but since seeing the JVC RS20 in action, I am a true film afficionado! I want the film quality picture, even if it doesnt look as shiny and poppy as 4:4 or FI.
well I dont think you can ever say something looking more real is a bad thing ....this is afterall audio visual sciences forum and the derectors are usually tring to make things look as real as possible in thier own respects....thats why they are always improving things like special effects...
I do know what you are saying though and agree with some of it myself including the totally videogame/cartoon looks of some of the out of the box picture settings of today....totally unrealistic....and that is a bad thing in my opinion just like the home videocamera motion look of some of the soap operas and seal budget flicks...definatly wouldnt pay extra for that....but it seems 120hz only looks that way with certian content from what I'm reading here...And I'm keeping an open mind here to learn more about it.

I say if you can really tell the difference you should think about flying jets for the military.

My dad is a fighter pilot and I am not... but we can both clearly see the difference. Less judder and panning backrounds don't seem to flicker.

My dad is a fighter pilot and I am not... but we can both clearly see the difference. Less judder and panning backrounds don't seem to flicker.

well than you dont count same Genes....JK.:)..I amended my original post....I can admit when I may be wrong...

I still think A lot of these guys are confusing seeing a difference between 120hz and 60hz with seeing a difference between automotion plus (Samsung) and Cinemotion (Sony) being enabled.

What does 120hz do to videogames? Does the processing time screw it up for Rock Band / Fighting Game type stuff?

I believe that 24fps material (film) is tranlsated into 96fps so that first two original frames are displayed and then two extrapolated frames, allowing 4 frames to be shown in the time one would have been before.

30fps material (video) is translated into 120fps in order to translate 3:2 pull down into 5:5. At least on the new Panasonic and Sanyo projectors.

i don't like 120 hz interpolation applied to most material as it makes it look unnatural.

Interesting that blurry pans and jerky motion are considered "natural". Perhaps smooth motion and clarity are really the normal situation and 24fps is the unnatural state of affairs.

I saw the movie Gran Torino in a theatre the other day. They panned across his grass to the neighbors grass, presumably to show you the beaten up nature of the lawn. It was so jerky and blurry because the pan had to be fast (who wants to see grass forever). I thought, wow we need faster cameras....then I see we can have faster projectors, a real start.

We are creatures of habit. I wonder if when color and sound came to the movies the critics all said the "art" is now gone from the movies and people will focus on hair color and voice quality and ignore the acting....no wait, that's exactly what happened. :confused:.

Interesting that blurry pans and jerky motion are considered "natural". Perhaps smooth motion and clarity are really the normal situation and 24fps is the unnatural state of affairs.

I saw the movie Gran Torino in a theatre the other day. They panned across his grass to the neighbors grass, presumably to show you the beaten up nature of the lawn. It was so jerky and blurry because the pan had to be fast (who wants to see grass forever). I thought, wow we need faster cameras....then I see we can have faster projectors, a real start.

We are creatures of habit. I wonder if when color and sound came to the movies the critics all said the "art" is now gone from the movies and people will focus on hair color and voice quality and ignore the acting....no wait, that's exactly what happened. :confused:.
You can get smoother panning with higher frames rates without interpolation. Don't lump interpolation and 120 hz together.

interesting that blurry pans and jerky motion are considered "natural". Perhaps smooth motion and clarity are really the normal situation and 24fps is the unnatural state of affairs.

I saw the movie gran torino in a theatre the other day. They panned across his grass to the neighbors grass, presumably to show you the beaten up nature of the lawn. It was so jerky and blurry because the pan had to be fast (who wants to see grass forever). I thought, wow we need faster cameras....then i see we can have faster projectors, a real start.

We are creatures of habit. I wonder if when color and sound came to the movies the critics all said the "art" is now gone from the movies and people will focus on hair color and voice quality and ignore the acting....no wait, that's exactly what happened. :confused:.

Interpolation is artificial and unnatural. It is "guessing" what in-between frames look like and creating new content that never existed to begin with. Film the same scene with a camera actually capturing 48fps or 72fps and compare that to an interpolated 24fps->120hz/fps and you would be shocked and horrified at what interpolation is doing to the picture.

you can get smoother panning with higher frames rates without interpolation. Don't lump interpolation and 120 hz together.

Exactly.

What does 120hz do to videogames? Does the processing time screw it up for Rock Band / Fighting Game type stuff?
It makes video games much better because its smoother. I haven't played rock band, but 1st and 3rd person shooters, action and racing all seem to benefit from FI. I was just playing Bourne Conspiracy for two hiours and decided to try it without FI and wow what a difference, everytime Bourne moved it was blurry and more choppy. Its a real nice improvement, and I haven't noticed any delays.

Interpolation is artificial and unnatural. It is "guessing" what in-between frames look like and creating new content that never existed to begin with. Film the same scene with a camera actually capturing 48fps or 72fps and compare that to an interpolated 24fps->120hz/fps and you would be shocked and horrified at what interpolation is doing to the picture.



Exactly.This is true, but directors aren't going with higher frame rates because then movies would have that cheap soap opera look, just like low budget non 24 fps movies without shallow DOF, just like the typical video camera. Having the 4:4 pulldown on does seem to smooth things out without the FI look, whch I guess is because of 96 or 120hz without the interesting look of FI.


When you say shocked and horrified at what FI is doing, what exactly are you refering to? Ive played with the FI on movies that I've seen 20 times and I never get that impression, it still looks like the same movie except smoother and with greater depth to the image. Unless your refering to the tearing that occurs on fast movement, because that can be distracting on some movies. Otherwise, I've found the FI to enhance my movie experience and gaming experience.

Interpolation is artificial and unnatural. It is "guessing" what in-between frames look like and creating new content that never existed to begin with. Film the same scene with a camera actually capturing 48fps or 72fps and compare that to an interpolated 24fps->120hz/fps and you would be shocked and horrified at what interpolation is doing to the picture.

But the point is the material is shot at 24fps not 96fps and realistically 24fps is pretty poor by today's standards. So while interpolation is only an approximation, it has to be pretty good for most material because in 1/24th of a second most normal subjects aren't going to make complex motions in the intervening time. As a consequence interpolation will be a pretty good guess most of the time.

Interpolation is definitely needed to improve the time resolution of 24fps; even if the improvement is only an approximation. It's about time cinema stepped up to better cameras that do 96fps but would be backwards compatible to old theatre equipment until new can be installed.

This is true, but directors aren't going with higher frame rates because then movies would have that cheap soap opera look,

How can providing more details both spacial and time wise, result in a cheap look? Are you saying that seeing a live play, where you don't have the camera in the way, results in a cheap look? In my experience it greatly enhances the performance and your feeling of intimacy. More detail brings you closer to reality and farther from the weird artificial look of 24fps cinematograpy.

Most likely the cheap soap opera look comes from a particular choice of lighting and angles rather than just providing more information to the viewer.

How can providing more details both spacial and time wise, result in a cheap look? Are you saying that seeing a live play, where you don't have the camera in the way, results in a cheap look? In my experience it greatly enhances the performance and your feeling of intimacy. More detail brings you closer to reality and farther from the weird artificial look of 24fps cinematograpy.

Most likely the cheap soap opera look comes from a particular choice of lighting and angles rather than just providing more information to the viewer.

To be honest, I would rather a film take me closer to fantasy and further from the ultra-realism of 120fps.

A photograph is more real, but does that make it more artistically than a painting? Color is more true to life, .... does that make black and white cinematography inferior?