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LG 24fps Bombshell - Page 2

post #31 of 58
7/1/10 at 11:01am
Thread Starter 
And this is the reply I received today:

Thank you for contacting LG Electronics. I will be glad to answer your concern.

The actual LCD panel will never change the number of times it refreshes the image it is displaying. This is 120 times per second so I suppose this is moot.

With Real Cinema on and TruMotion off, the TV will give the appearance of 48fps. With both real Cinema and TruMotion on the source material will play at 120fps.

If you have other questions or concerns, please do not hesitate to contact us again either via email, or by calling our customer service division at 800-243-0000 at your convenience.

Scott B.
E-mail Administrator
Customer Interactive Center
LGEAI
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post #32 of 58
7/1/10 at 11:14am
Thread Starter 
Another reply received today from a different person:

Thank you for contacting LG Electronics. We are always glad to assist you.

I absolutely understand your concern, and sincerely apologize for any inconvenience you may have experienced.

The fact is that the panel's refresh rate is different than the picture's refresh rate. The panel will always refresh at 120 fps, while the picture will always refresh at 24fps.

The difference is that when you enable real cinema, the television will refresh each one of the 24 frames five times (it will repeat each frame five times). In layman's terms, the television will be displaying 24 original frames, which were copied 5 times, to match the display's speed, which is 120fps.

If you have other questions or concerns, please do not hesitate to contact us again either via email, or by calling our customer service division at 800-243-0000 at your convenience.

Alfred Q.
E-mail Administrator
LGEAI | Customer Interactive Center
Contact: customerservice@lge.com
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post #33 of 58
7/1/10 at 3:10pm
Thread Starter 
Just received another reply, and this one has me a bit confused:

Thank you for contacting LG Electronics. We are always glad to assist you.

The actual refresh rate of blu-ray content formatted as 1080p 24 is 24fps. However, the television's panel will always refresh at 120fps.

If you have other questions or concerns, please do not hesitate to contact us again either via email, or by calling our customer service division at 800-243-0000 at your convenience.

Alfred Q.
E-mail Administrator
LGEAI | Customer Interactive Center
Contact: customerservice@lge.com
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post #34 of 58
7/1/10 at 3:16pm
Alfred knows what he's talking about, Peter does not.

So it is as we suspected, real cinema simply enables 5:5. With it off you get 2:3. trumotion enables the interpolation
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post #35 of 58
7/1/10 at 3:20pm
Thread Starter 
Quote:
Originally Posted by shaddix View Post

Alfred knows what he's talking about, Peter does not.

So it is as we suspected, real cinema simply enables 5:5. With it off you get 2:3. trumotion enables the interpolation

Not being an expert on all this I have to ask, is refresh rate and fps the same thing? I would think not. If not, then how is Alfred right when he says the TV always refreshes at 120fps?
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post #36 of 58
7/1/10 at 3:28pm
Quote:
Originally Posted by ambizytl View Post

Not being an expert on all this I have to ask, is refresh rate and fps the same thing? I would think not. If not, then how is Alfred right when he says the TV always refreshes at 120fps?

refresh rate is the frame rate of the display(120fps or 120hz), this is different from your source framerate(24fps or 24hz)
refresh rate just means how often the image on the screen is updated.(whether it's a different frame from your source or not, doesn't matter)

So a refresh rate of 120fps(or 120hz same thing) and a source framerate of 24fps with realcinema on means that the screen shows the same image 5 times in a row, then shows the next image 5 times in a row, and so on for 24 distinct images each shown 5 times in a row for a total 120fps.
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post #37 of 58
7/2/10 at 6:44am
Thread Starter 
Quote:
Originally Posted by shaddix View Post

refresh rate is the frame rate of the display(120fps or 120hz), this is different from your source framerate(24fps or 24hz)
refresh rate just means how often the image on the screen is updated.(whether it's a different frame from your source or not, doesn't matter)

So a refresh rate of 120fps(or 120hz same thing) and a source framerate of 24fps with realcinema on means that the screen shows the same image 5 times in a row, then shows the next image 5 times in a row, and so on for 24 distinct images each shown 5 times in a row for a total 120fps.

I knew about the 5:5 pulldown but question was 24fps as source from Blu-ray disc. The only reference about fps was from Scott B. "The TV will never actually run at 24fps."

So, perhaps the bottom line here is TV will never run at 24fps in the sense of an actual 24fps, but does 24fps 5 times to give 120fps?
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post #38 of 58
7/2/10 at 9:39am
Quote:
Originally Posted by ambizytl View Post

I knew about the 5:5 pulldown but question was 24fps as source from Blu-ray disc. The only reference about fps was from Scott B. "The TV will never actually run at 24fps."

So, perhaps the bottom line here is TV will never run at 24fps in the sense of an actual 24fps, but does 24fps 5 times to give 120fps?

Look you really need to actually read up on the things you're asking about before bombarding the forum with this mess. No modern LCD displays 24p at 24hz. Baseline modern LCDs are 60 hz. The problem with 60hz is that its not evenly divisible by both 60 and 24, that's the magic ratio to have to avoid 3:2 pulldown. This is why 120 hz and 240 hz lcds are so popular. 120 and 240 are both evenly divisible by both 24 and 60. This LG is doing the standard 5:5 24 to 120 without need for 3:2. Its perfect. Now stop asking silly questions.
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post #39 of 58
7/2/10 at 3:07pm
Thread Starter 
Quote:
Originally Posted by dpak2005 View Post

Look you really need to actually read up on the things you're asking about before bombarding the forum with this mess. No modern LCD displays 24p at 24hz. Baseline modern LCDs are 60 hz. The problem with 60hz is that its not evenly divisible by both 60 and 24, that's the magic ratio to have to avoid 3:2 pulldown. This is why 120 hz and 240 hz lcds are so popular. 120 and 240 are both evenly divisible by both 24 and 60. This LG is doing the standard 5:5 24 to 120 without need for 3:2. Its perfect. Now stop asking silly questions.

Like I said, I am far from being an expert on this. The fact remains the manual is wrong, and the manual comes from LG. Thus, me not being an expert puts me in good company.
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post #40 of 58
7/2/10 at 3:30pm
When the manual says it is display at 24fps it does not mean that the screen is actually being refreshed at 24fps.
I belive that your TV is a 120 Hz model which means when it says it is displaying at 24fps it means that each frame is being left in the display's output buffer for 1/4 of a second and therfore each of the 24fps frames is being refreshed 5 times since 5x24=120.
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post #41 of 58
7/2/10 at 4:07pm
Thread Starter 
Quote:
Originally Posted by walford View Post

When the manual says it is display at 24fps it does not mean that the screen is actually being refreshed at 24fps.
I belive that your TV is a 120 Hz model which means when it says it is displaying at 24fps it means that each frame is being left in the display's output buffer for 1/4 of a second and therfore each of the 24fps frames is being refreshed 5 times since 5x24=120.

The manual states:

DVD and Blu-ray movies are filmed at 24 frames per second (fps). With LG Real Cinema, every frame is consistently processed 5 times in 1/24 of a second producing 120 fps with TruMotion or 2 times in 1/24 of a second producing 48 fps without TruMotion, thus totally eliminating the judder effect.
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post #42 of 58
7/2/10 at 4:29pm
Quote:
Originally Posted by ambizytl View Post

The manual states:

DVD and Blu-ray movies are filmed at 24 frames per second (fps). With LG Real Cinema, every frame is consistently processed 5 times in 1/24 of a second producing 120 fps with TruMotion or 2 times in 1/24 of a second producing 48 fps without TruMotion, thus totally eliminating the judder effect.

Look dude, STOP OBSESSING. The TV is 120hz TV. It's DESIGNED for 24p. When an LCD says it supports 24P it doesn't mean it displays it natively at 24hz. There are NO 24hz LCDs. It just means it displays it at an even multiple of 24. Be that 48 hz (2:2) or 120 hz (5:5) it DOESN'T MATTER. It will be judder free. You need to learn about 24p support.
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post #43 of 58
7/2/10 at 4:46pm
Thread Starter 
Quote:
Originally Posted by dpak2005 View Post

Look dude, STOP OBSESSING. The TV is 120hz TV. It's DESIGNED for 24p. When an LCD says it supports 24P it doesn't mean it displays it natively at 24hz. There are NO 24hz LCDs. It just means it displays it at an even multiple of 24. Be that 48 hz (2:2) or 120 hz (5:5) it DOESN'T MATTER. It will be judder free. You need to learn about 24p support.

Time for you to understand why I post. If you read my post you should know that was in reply to someone who posted to me. You seem to be very "hurt" by my posting. May I suggest you take an aspirin or something and try to relax.
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post #44 of 58
7/2/10 at 4:48pm
Quote:
Originally Posted by ambizytl View Post

Time for you to understand why I post. If you read my post you should know that was in reply to someone who posted to me. You seem to be very "hurt" by my posting. May I suggest you take an aspirin or something and try to relax.

How long are you going to keep this nonsense going? This LG TV displays 24p the exact same way as 99% of 2010 LCDs too, and the preferable way, 5:5 pulldown. That's what the manual is trying to tell you, if you could actually learn to interpret it. This entire post is a result of your fundamental lack of knowledge of 24p support in HDTVs. I recommend you read up on the subject,
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post #45 of 58
7/2/10 at 5:50pm
Quote:
Originally Posted by ambizytl View Post

The manual states:

DVD and Blu-ray movies are filmed at 24 frames per second (fps). With LG Real Cinema, every frame is consistently processed 5 times in 1/24 of a second producing 120 fps with TruMotion or 2 times in 1/24 of a second producing 48 fps without TruMotion, thus totally eliminating the judder effect.


I believe this a very strange wat of saying if you don't use 5:5 pulldown to eliminate frame rate judder you can use frame interpolation to insert an extra frame to eliminate any 24 fps Judder between each pair of 24fps frames essentialy doubling them to 48 fps.
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post #46 of 58
7/3/10 at 6:38am
Thread Starter 
Quote:
Originally Posted by walford View Post

[/b]
I believe this a very strange wat of saying if you don't use 5:5 pulldown to eliminate frame rate judder you can use frame interpolation to insert an extra frame to eliminate any 24 fps Judder between each pair of 24fps frames essentialy doubling them to 48 fps.

I don't know if strange is what I would use, perhaps wrong is a better description. The following post seems to explain it better, although I don't know why he suggests Real Cinema Off with content other than 24p because I thought Real Cinema On has no effect on content not in 24p with TruMotion Off:

About LG TruMotion 240Hz + Real Cinema

*BD Player Output 24p material -> Real Cinema On -> TruMotion Off = 5:5 Pulldown 24fps

*BD Player Output 24p material -> Real Cinema On -> TruMotion Low = 5:5 Pulldown 48fps

*BD Player Output 24p material -> Real Cinema On -> TruMotion High = 5:5 Pulldown 96fps

*BD Player Output 60p material -> Real Cinema Off -> TruMotion Off = 60fps

*BD Player Output 60p material -> Real Cinema Off -> TruMotion Low = 120fps

*BD Player Output 60p material -> Real Cinema Off -> TruMotion High = 240fps

*Because TruMotion is Frame Interpolation System, this has nothing to do with 24 fitting in 120Hz and 60Hz because you don't need frame interpolation system to pulldown
*5:5 pulldown is repeating a frame for 5 times that has nothing to do with Frame Interpolation's "Frame Insertion" and Effect and which will still be 24fps. 5:5 will give you true 24 frames without 3:2's pulldown which will degrade image quality and judder a little and not a smooth 24fps. Whereas Frame Interpolation System adds frames to the scene which increases the number of frames being displayed.

*Real Cinema On uses 5:5 pulldown from Panel Running at 120Hz
(Setting Refresh Rate to 120Hz for 24p Material) True 24p
*Real Cinema Off uses 3:2 pulldown from Panel Running at 60Hz
(Setting Refresh Rate to 60Hz for 24p Material) Degraded 24p

Only enable Real Cinema when you plan to watch Blu Ray movies that are done at 24p, otherwise keep it off like when you play games or watching dramas, sports.
http://www.avsforum.com/avs-vb/showt...3#post18387073
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post #47 of 58
7/3/10 at 1:18pm
5:5 pulldown of 2fps content always give you 120Hz content since you can't change the fact that 5x24= 120.
Tru motion off gives you no interpolation as stated.
Tru motion low only frame interopolates the the largr moving objects in order to reduce interpolation artifacfact.
Tru motion high interpolates all objects and can artifacts around the smaller objects.

What may be happening is that with both enabled Frame interpolation is occuring between each pair of 24fps frames which gives you 48fps. And then 5:5 pulldown is applied to each of the 48 frames. If this is what is happening then there is no frame rate judder or less or no 24 flim rate Judder.
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post #48 of 58
7/3/10 at 3:31pm
Quote:
Originally Posted by ambizytl View Post

I don't know if strange is what I would use, perhaps wrong is a better description. The following post seems to explain it better, although I don't know why he suggests Real Cinema Off with content other than 24p because I thought Real Cinema On has no effect on content not in 24p with TruMotion Off:

About LG TruMotion 240Hz + Real Cinema

*BD Player Output 24p material -> Real Cinema On -> TruMotion Off = 5:5 Pulldown 24fps

*BD Player Output 24p material -> Real Cinema On -> TruMotion Low = 5:5 Pulldown 48fps

*BD Player Output 24p material -> Real Cinema On -> TruMotion High = 5:5 Pulldown 96fps

*BD Player Output 60p material -> Real Cinema Off -> TruMotion Off = 60fps

*BD Player Output 60p material -> Real Cinema Off -> TruMotion Low = 120fps

*BD Player Output 60p material -> Real Cinema Off -> TruMotion High = 240fps

*Because TruMotion is Frame Interpolation System, this has nothing to do with 24 fitting in 120Hz and 60Hz because you don't need frame interpolation system to pulldown
*5:5 pulldown is repeating a frame for 5 times that has nothing to do with Frame Interpolation's "Frame Insertion" and Effect and which will still be 24fps. 5:5 will give you true 24 frames without 3:2's pulldown which will degrade image quality and judder a little and not a smooth 24fps. Whereas Frame Interpolation System adds frames to the scene which increases the number of frames being displayed.

*Real Cinema On uses 5:5 pulldown from Panel Running at 120Hz
(Setting Refresh Rate to 120Hz for 24p Material) True 24p
*Real Cinema Off uses 3:2 pulldown from Panel Running at 60Hz
(Setting Refresh Rate to 60Hz for 24p Material) Degraded 24p

Only enable Real Cinema when you plan to watch Blu Ray movies that are done at 24p, otherwise keep it off like when you play games or watching dramas, sports.
http://www.avsforum.com/avs-vb/showt...3#post18387073

Yes, Real Cinema On only affects 24p sources, so it can be safely left On. Other than that, I think KakimotoRift's post is correct.

Again, the refresh rate on the LH90 is always 120Hz -- whether it uses TruMotion or not, or if it uses 5:5 pulldown, 3:2 pulldown etc. The framerate, however, can really be whatever. It's the refresh rate of the output device that has to be a divisible number of 120.
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post #49 of 58
7/3/10 at 3:42pm
Thread Starter 
But the manual is wrong saying Real Cinema On with TruMotion Off gives 48fps, right?

"DVD and Blu-ray movies are filmed at 24 frames per second (fps). With LG Real Cinema, every frame is consistently processed 5 times in 1/24 of a second producing 120 fps with TruMotion or 2 times in 1/24 of a second producing 48 fps without TruMotion, thus totally eliminating the judder effect."
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post #50 of 58
7/3/10 at 4:01pm
For the 10th time, yes.

It's not mathematically possible. TruMotion is a frame interpolation technique; without it, there aren't any new frames created. If the output device is outputting 24fps and there aren't any new frames created, then how is it possible that it's outputting 48fps? The only way that's possible, is with TruMotion on Low. On Low, it essentially doubles the frames by inserting intermediate frames between each of the 24 original frames, therefore, doubling the framerate.

Now with TruMotion on High is what I'm a little unsure of. KakimotoRift thinks that the backlight strobing inserts two more frames on High, like this:
Original frame -- backlight strobed frame -- MEMC frame -- backlight strobed frame -- next original frame. So 96fps. He could be right, but I dunno how to actually check.

Whether TruMotion is on Low/High or Off, if Real Cinema is On, 5:5 pulldown is always used for 24p sources and the LH90 always refreshes at 120Hz. The only thing that changes, is the framerate.
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post #51 of 58
7/3/10 at 4:27pm
Thread Starter 
Quote:
Originally Posted by rahzel View Post

For the 10th time, yes.

It's not mathematically possible. TruMotion is a frame interpolation technique; without it, there aren't any new frames created. If the output device is outputting 24fps and there aren't any new frames created, then how is it possible that it's outputting 48fps? The only way that's possible, is with TruMotion on Low. On Low, it essentially doubles the frames by inserting intermediate frames between each of the 24 original frames, therefore, doubling the framerate.

Now with TruMotion on High is what I'm a little unsure of. KakimotoRift thinks that the backlight strobing inserts two more frames on High, like this:
Original frame -- backlight strobed frame -- MEMC frame -- backlight strobed frame -- next original frame. So 96fps. He could be right, but I dunno how to actually check.

Whether TruMotion is on Low/High or Off, if Real Cinema is On, 5:5 pulldown is always used for 24p sources and the LH90 always refreshes at 120Hz. The only thing that changes, is the framerate.

It is kind of amusing LG has the same Real Cinema information in the manual for previous models. You would think that by now the manual would be corrected. Anyway, I was watching baseball via DirecTV and picture was absolutely perfect. Even the black bars during commercials were perfect. Flesh tones are amazing with color temperature set to Warm, just very natural looking. So now I have watched baseball, boxing, and HD content via DirecTV and my settings seem to be working out fine, no problems. I better stop now as this is getting off-topic.
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post #52 of 58
3/17/12 at 3:28pm
Quote:
Originally Posted by ambizytl View Post

But the manual is wrong saying Real Cinema On with TruMotion Off gives 48fps, right?

"DVD and Blu-ray movies are filmed at 24 frames per second (fps). With LG Real Cinema, every frame is consistently processed 5 times in 1/24 of a second producing 120 fps with TruMotion or 2 times in 1/24 of a second producing 48 fps without TruMotion, thus totally eliminating the judder effect."


You are confusing frame rate with refresh rate. What the manual refers to as fps is actually refresh rate. TruMotion refers to 120hz tvs and without TruMotion refers to 60hz tvs.

See this link:

http://www.redbearinc.com/LG/pdf/Real_Cinema.pdf
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post #53 of 58
3/17/12 at 3:55pm
From the manual of my 2011 LG 42LK450:

"Real Cinema or Film Mode

Makes video clips recorded in film look more natural by eliminating judder effect.
DVD and Blu-ray movies are filmed at 24 frames per second (fps). With LG Real Cinema, every frame is consistently processed 5 times in 1/24 of a second producing 120 fps with TruMotion or 2 times in 1/24 of a second producing 48 fps without TruMotion, thus totally eliminating the judder effect.
This function can also work when TruMotion is off."

I just read through this thread and can explain why the manual says what it says. This same explanation is for both 120Hz TVs AND 60Hz TVs (my LK450 is 60Hz). When it says 48fps without TruMotion it means 60Hz TVs like my LK450 NOT a 120Hz TV with TruMotion set to OFF. WITHOUT the TruMotion feature is not the same as having it and leaving it OFF. This is what was confusing the OP since he did not realize that the manual was referring to LG LCD TVs in general and not just his 120Hz set.

Also, when it says "thus totally eliminating the judder effect," it means any judder created by 2:3 pulldown not the inherent judder of 24fps content like BD movies.

I'm 100% sure about this since, having Real Cinema ON on my LG 60Hz LCD TV eliminates 2:3 pulldown judder by using 2:2 pulldown instead but definitely doesn't do frame interpolation to create 48 unique frames out of 24 frames in the source. If it did, BD movies would have the SOE and that would be easily visible.


For what it's worth, my LK450 user manual also makes references to LG Plasmas in addition to TruMotion, LED Local Dimming, and 20-pt grayscale. It is, however, just a 60Hz CCFL-LCD TV that has none of those features. The front cover of the manual explains why (see attached).

 

eng.pdf 399.2451171875k . file
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post #54 of 58
3/17/12 at 4:03pm
With "sample and hold" displays like LCDs there is no difference between 24Hz and 120Hz display as long as the 120Hz display repeats every frame 5 times. Since there is no intervening time between frames, it is for all intents and purposes exactly the same as 24Hz. The reason movie theaters show film at 48Hz is because the shutter blocks the light half of the time, so to prevent flicker they must refresh at double the frame rate. LCDs don't flicker because the light is never blocked. By the way, DLP cinema projectors show movies at 24Hz.
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post #55 of 58
3/17/12 at 4:12pm
Quote:
Originally Posted by HokeySmoke View Post

With setup and hold displays like LCDs there is no difference between 24Hz and 120Hz display as long as the 120Hz display repeats every frame 5 times. Since there is no intervening time between frames, it is for all intents and purposes exactly the same as 24Hz. The reason movie theaters show film at 48Hz is because the shutter blocks the light half of the time, so to prevent flicker they must refresh at double the frame rate. LCDs don't flicker because the light is never blocked. By the way, DLP cinema projectors show movies at 24Hz.

good point but I believe the term is "sample and hold"

On an LCD, 1:1, 2:2, 5:5, and 10:10 pulldown would all look the same since the repeated frames are just held not flashed like a CRT or Plasma.
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post #56 of 58
3/17/12 at 4:14pm
Quote:
Originally Posted by turbo3 View Post

You are confusing frame rate with refresh rate. What the manual refers to as fps is actually refresh rate. TruMotion refers to 120hz tvs and without TruMotion refers to 60hz tvs.

See this link:

http://www.redbearinc.com/LG/pdf/Real_Cinema.pdf

exactly

your link states:

"In addition, our 1080p panels that
operate at 60Hz will also accept the 24p input
signal so that each of the original 24 film frames
are flashed 2 times per second."

technically, the frames aren't flashed twice but just held for 1/24 of a second instead of 1/48 of a second
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post #57 of 58
3/18/12 at 9:22am
The refresh rate of LCD TVs is the fixed rate at which the content of the screen is displayed from the contents of a separately software/firmware maintained output buffer.
For a LCD TV with a 120Hz refresh rate and the content of the output buffer is only changed every 1/60th of a second, the actual frame rate is 60fps since the frames are refreshed/displayed twice in one second.
For a 60Hz refresh rate TV and if the content of it's output buffer every 1/24th of a second then the actual display will have 3;2 Judder since 1/2 of the frames will be displayed 3 times and the other 1/2 of the frames will be displayed 2 times since 3X12+2X12=60.
On many Plasma TVs the actual refresh rate of the screen can be changed from 60Hz to 48Hz, 72Hz, or 96Hz which will eliminate 3:2 pulldown Judder since each actual frame is displayed the same number of times( 2, 3 or 4 times)
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post #58 of 58
3/18/12 at 9:33am
Quote:
Originally Posted by walford View Post

For a 60Hz refresh rate TV and if the content of it's output buffer every 1/24th of a second then the actual display will have 3;2 Judder since 1/2 of the frames will be displayed 3 times and the other 1/2 of the frames will be displayed 2 times since 3X12+2X12=60.

Actually, the 60Hz LGs (LCD TVs) can do both 60Hz and 48Hz. The 48Hz mode eliminates the need for 2:3 pulldown and the judder it creates, using 2:2 pulldown instead.
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