TV Hz game gets taken to new levels, for no reason at all

LG is taking the Hz game to the next level with its TrueMotion LCD TV. LG will be showing off its overkill 480Hz TV at this years CES. While Sony just got done with an advertisement campaign for its 240 Hz TVs it goes to show that Hz is the new mega-pixel race.

Our technology history has been filled with many size races; always based around the idea that bigger is better. You can look back to the early days of AMD vs Intel where clock speed was the defining factor of a CPU, mega-pixel race for digital cameras and now the Hz race for televisions. As it is now understood for the CPU market clock speed is not an indication of performance, nor is a high mega-pixel camera anything without a decent lens and higher Hz is not any better for televisions.

To fully understand why the higher Hz is not always better (and not worth the extra coin) there are some basics that need to be understood. The benchmark of 120Hz allows for video and film to be played back without the need of extra pull down technologies. Film is shot at 23.94 FPS (frames per second) which is rounded up to 24 FPS but the USA and many other countries adopted the NTSC standard which shoots video at 60 FPS technology.

The problem is that some parts of the world shoot in 24 FPS while others shoot at 60 FPS. The two formats are not directly compatible and need a "pull down" technology to make the transition. For countries that use SECAM standard a 2:2.1 pull down can be used which results to ~5% speedup ( 24 FPS becomes 25 FPS). Because of the slight speedup an audible pitch difference is noticeable but generally an audio filter can be used to disguise the difference.

NTSC with its 60 Hz can't be slowed down to the 20 or 30 Hz needed to reproduce the 24 FPS. For this a 3:2 pull down technology is used to supplement the interlaced nature of broadcast television. It essentially involves repeating or mixing frames that can result in the "judder" which is a result of the speed difference and the mixing of frames. It will be more apparent in slow panning shots where only subtle movement occurs, the faster the movement the harder to see the "judder".

120 Hz television can remove the "judder" by accepting 24 Hz input and using a 5:5 (24 * 5 = 120) pull down which shows each frame 5 times for smoother playback to the viewer. No further technology is needed as the format can be replayed in equal parts with no distortion. The same works for 60FPS as a 2:2 pull down can be used ( 60*2 = 120) resulting in fluid motion and no further technology is needed. This equal distribution results in negligible "ghosting" and is the optimal Hz for the current television standards.

Why is all that background information relevant to the 240Hz TV from Sony and the 480 Hz TV from LG? It goes to show that the Hz race is nothing more than a frivolous attempt at getting more dollars out of your pocket. The difference between the 120,240 and 480Hz has a diminishing return affect as 120Hz is the optimal refresh rate (as per dollar to benefit ratio). Be warned that the TV manufactures are going to attempt to brainwashing the consumer into thinking the higher the Hz the better the TV. Take it all with a giant grain of salt as 3Ghz P4 is not better than a 2Ghz Core 2 Duo.

Special thank to "Random John" for his expertise on the subject.

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That quote is completely incorrect. Hz concerns itself only with the frequency that the display refreshes itself at. If I'm using a CRT monitor set to 75Hz and I have it displaying a static image for 30 seconds I haven't changed the Hz.

geoken said,
If I'm using a CRT monitor set to 75Hz and I have it displaying a static image for 30 seconds I haven't changed the Hz.

Not necessarily. If you have static image for 30 seconds, the "in-between" frames will be exactly the same as all the keyframes.
It's completely possible (assuming there's some sort of a buffer present) that given a 60Hz input, the intermediate of one frame and the next could be calculated and output instead of leaving the same image there for two frames. However, as people have already mentioned, above 120Hz this becomes pointless, since we "can't see that fast", as it were. (Hell, 60Hz is fine for many things, but double it to be safe, eh? :D)

Yeah, but if you read what the guy posted he basically said if the image is repeated than it wouldn't really be 120Hz, it would actually be less. The problem is that he's combining Hz and frame rate into on indistinguishable thing. I'm sure anyone can attest to the visible difference between a CRT at 50Hz and a CRT at 75+Hz, even when looking at a static image.

Also, I never said that interpolation isn't possible. I only said that the lack of interpolation doesn't negate the fact that it's 120Hz.

carmatic said,
but like, this is an lcd screen
dont they already do kind of the opposite of interpolation to speed up the response time?

The "opposite of interpolation" is no interpolation. You either do it or you don't. Hmm, not sure about computer LCD's, but if I was a designer, I would imagine building a computer LCD not interpolating but one intended for TV viewing doing it. :S

I hate the 120Hz crap, and I hate how some TVs actually force the feature on you and you cannot turn it off. Luckily mine does not have it and I never plan to buy a TV that does have such a stupid feature.

geoken said,
This is great. It'll drive down the prices for all of us who realize the uselessness.


Can't say it any better. For those who know, save. Just because they make it, doesn't mean we have to buy it. Eventually we'll have to replace what we have now and by that time, for some, there'll be something worth investing in.

Higher Hz isn't just money out of your pocket, it helps because having a higher refresh will help mask the line crawling effect LCDs have.

I got the Sony 120 MHz 40" TV, and love it, i also have a 32" Sony, 'S' line and i can tell the difference. I have enabled the 120 on the game systems and cable, and we can tell the difference. I got mine at Costco, and got a free Blue Ray unit, and all for under $1100 3 months ago. It was $100 more then the non 120 MHz. Everyone who watches it ask about the differences, and why it looks better.

i used to do that with my crt monitor with those video card tweaking programs that run in your taskbar... i know of someone who used to force his refresh rate to 200hz or something and the screen goes all yellow and stuff

There needs to be some corrections with this article to explain the differences between refresh rate and frame rate.

HDTV has 18 different standards with 1080p60 being the highest but most cable companies don't support it because it uses to much bandwidth. HDTV should have gotten rid of interlacing forever for source material and stuck with true progressive frames. If you have 60 fields and you sew them together then they become 30 frames which is not the same for true 60 progressive frames.

HDTV should be 1080p24, 1080p30 and 1080p60, that would have saved a lot of confusion. Since most Hollywood movies are still 24p it would save bandwidth and the TV set could then have a higher refresh rate like 60 or 120 to remove any flicker.

Why is 240hz, or even 480hz ridiculous. Plasma TV's are 480Hz.

I ended up buying a plasma TV for console gaming mainly because of the Hz. Just like in PC gaming, the faster the refresh rate, the more accurate and "clean" the picture is. Most of what this article states and what I've read here is personal opinion BS and not fact.

The facts are, the higher the refresh rate, the cleaner the picture. My brother is ****ed about his Samsung 46" Series 7 120Hz LCD after playing the same games and movies on my screen and seeing NO blocking or flickering during scrolling or heavy screen action.

If you go into any Best Buy and watch a sports game on a 120Hz TV compared to a 480Hz plasma, the difference is undeniable, unless you're just being stubborn. You will really start to notice the artifacts on the screen on the slower Hz TV.

zim2323 said,
The facts are, the higher the refresh rate, the cleaner the picture. My brother is ****ed about his Samsung 46" Series 7 120Hz LCD after playing the same games and movies on my screen and seeing NO blocking or flickering during scrolling or heavy screen action.

If you go into any Best Buy and watch a sports game on a 120Hz TV compared to a 480Hz plasma, the difference is undeniable, unless you're just being stubborn. You will really start to notice the artifacts on the screen on the slower Hz TV.

Sorry but... don't you think it's just the fact that a Plasma screen is generally faster than an LCD Panel, considering LCD's have a "response time"? :P

The difference in artifacting between the Plasma and the LCD you mention is due to the electronics inside and the nature of the panel. It has NOTHING to do with the 120 hz or higher debate. Get educated.

480hz is beautiful. I've seen those low Hz TVs at the store and their pictures look like badly encoded mpg files. ON BLUERAY! Why? Indeed, these 480 Plasmas do make a difference.

Izlude said,
480hz is beautiful. I've seen those low Hz TVs at the store and their pictures look like badly encoded mpg files. ON BLUERAY! Why? Indeed, these 480 Plasmas do make a difference.


Um, take store TV displays with a grain of salt. It's not unheard of to take measures ensuring certain panels look better than other panels on the showroom floor, when the same difference won't be found at home.

I'll stick to doing my own research, looking at reviews online, and not buying a model that's been out for less than half a year (issues don't always pop up over night).

@OP, did you even read what that refresh rate means? It's just the highest common denominator. Any lower framerate content will get its frames repeated until it's time for the next one to be displayed. Watching 24fps progressive content at 24hz or 480hz will look exactly the same.

I really do think these companies throw out all this info to confuse the average consumer. This also gives the guys at Best Buy, etc. even more lingo to confuse the couple that just want to watch a little Sunday Night Football & Desperate Housewives. One of the biggest misconceptions I see on the forums is that people seem to think that the 120hz is what gives movies, TV shows, etc that "Soap Opera" look. As if you are watching a play live in your living room. This is completely false. If you purchase a TV with the ability to refresh 120hz then it's going to refresh at 120hz 100% of the time. You can not turn this off or change it from low to high. What you can do is control the motion blur enhancement feature. Each manufacture calls it something different. Sony calls it "Motion Flow" Samsung calls it "Movie Plus". These features are what causes the "so real, it's as if you can reach out and touch them" look. The calibration pros says to turn this feature completely off and others can't watch TV without it. I have the Sony 52" W4100 and I leave it on medium for everything. If I want to show off my panel, I'll crank it up to high. But when I do, the first question I get asked is "Did you just turn on the 120hz?" The answer is NO.

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