120HZ vs 60HZ LCD

tigerfan33

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I am looking to get a hdtv for the bedroom. I have heard a lot about the 120hz fresh time on some new lcd. Does the pic look $800 more dollars better??? I am a big sports nut so I would be watching sports mostly, some movies.
 
The primary goal of 120Hz displays is to eliminate judder when displaying film originating material (24fps) especially noticable on slow horizontal pans.
With 60 HZ displays such material is shown for different length of time: every odd frame - twice, every even frame - 3 times (12*2+12*3=60). It's called 3-2 pulldown.
A 120HZ display shows every frame 5 times (5*24=120), hence, no judder.

There is no difference in presenting 60Hz footage (what sports mostly uses) between those two displays.

Diogen.
 
I went to a local retail store and looked at several differnet tvs that had the 120hz. I could tell no difference between the 120 or the 60hz. Only time when I could see a diffrence was when the demo was running. Live tv was just the same as the other lcds. I wonder what the next gimmick will be to come out next to raise prices??
 
I went to a local retail store and looked at several differnet tvs that had the 120hz. I could tell no difference between the 120 or the 60hz. Only time when I could see a diffrence was when the demo was running. Live tv was just the same as the other lcds. I wonder what the next gimmick will be to come out next to raise prices??
I dont know but this "Judder" that some of us cannot even see is the same excuse the BD fanboys use to bash some HD DVD players.
 
Judder is real and very noticable on very specific footage (as described above).
Watch HDNet "Nothing but trailers". Wait for a slow scene with horisontal panning.
Look at the left/right edge. You'll notice the movement being not smooth but jumpy. This is judder.

Store demos are rarely in that category, even if running movie trailers.

If you don't see it - it's not worth paying extra for that.

Diogen.
 
Also be aware that 120HZ is new this year too, and there are still some bugs to be worked out with it. It is mainly used to address the 24 frame movie problem. Sports is usually a video feed so designed for a 60HZ display, and the 120HZ benefit seems to be much smaller. As usual in a couple of years they will have the processing speed improved and the methods perfected to make it truely worthwhile.
 
Also be aware that 120HZ is new this year too, and there are still some bugs to be worked out with it.
Very much so.
Some implementations are not "clean" 120Hz, but more like "frame-doubling" on top of 60Hz.
"Wobulation" of sorts. Nothing but marketing.

Diogen.
 
hi guys

This statement is DEAD WRONG:
A 120HZ display shows every frame 5 times (5*24=120), hence, no judder

120 HZ for LCDs was created for decreasing motion artifacting / image retention / trails. LCD panels still do 3:2 pull down.
 
Odd, Sony claims 5:5 pulldown with 24 frame sources, from the XBR4 LCD page:

Motionflow™ 120 Hz with Full HD high frame rate capability
Taking motion performance to the next level requires innovation and expertise. Enter Sony's Motionflow™ High Frame Rate technology. Motionflow™ detects the incoming video signal and applies the appropriate processing for optimum motion reproduction. Taking full advantage of film sourced 24fps encoded content available on DVD and Blu-ray Disc, Motionflow™ eliminates the need for 3:2 pulldown and delivers smooth, judder free video, faithfully preserving the integrity of the original film. When 60fps content is detected, Motionflow™ doubles the amount of frames and uses real-time calculation to create a new level of natural motion reproduction. You'll experience movies and sports with a greater sense of realism than ever before.
 
This statement is DEAD WRONG...
120 HZ for LCDs was created for decreasing motion artifacting / image retention / trails. LCD panels still do 3:2 pull down.
Can you elaborate on this?
The 3:2 pulldown is because of 60Hz vs. 24Hz (24fps).
Why do you need it on 120Hz displays?

Unless you are talking about achieveng 120Hz by frame doubling of 60Hz (see post 7 above).

I think exactly what you do... about your last statement. :)

Diogen.
 
film is at 24 fps
video is at 30 fps

Historically, projectors have been at 60 hz so film has had to be converted to 30 (or 60). This process is called 3:2 pull down. 3:2 pull down creates an artifact known as jutter. Companies like Pioneer have introduced plasmas at 72Hz which does not require 3:2 pull down and just multiplies each frame of 24 by 3 to make 72 hz. This eliminates jutter.

LCD panels have a problem known as lag which is related to refresh times. This is especially evident in fast motion content (ie football game). To minimize lag LCD manufacturers are putting more frames on the screen per second. In addition they have been adding black frames to the signal to create a better black level (this is very cool). If they simply took 24 and made it 120 there would be no jutter. However, they are not doing this. They are still using 3:2 pull down.

Regards

Gregg
 
3:2 pull down creates an artifact known as jutter.
You mean judder, not jitter, right?
Telecine - Wikipedia, the free encyclopedia

So, are you saying LCD - as technology - can't as of today run 5x24 the same way it does 3x24=72Hz, i.e. today's implementation of 120Hz on LCDs is "crippled"?
Or are you saying 120Hz on LCD never had judder-free playback of 24fps material as a goal?

Diogen.

EDIT: Can you also please comment on Paidgeek's statement
The new XBR sets (XBR4/5) will not only display 24p as 5:5, but they will also take 60i, convert it to 24p, then display it at 120hz 5:5.
taken from here
Blu-ray Forum - View Single Post - Insiders Thread
 
Last edited:
i meant jutter

Judder refers to the motion artifact created from film moving through a sprocket.

Many sources use the 2 terms interchangably.
 
We must be talking about different things.

I thought I know what judder is (wiki link above)
but have never seen terms like jutter and/or sprocket used wrt movie/video playback...

Let's leave it at that.

Diogen.
 
i dont think there are any LCD panels out there that are doing 5:5. I could be mistaken (but I dont think so).
 

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