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I bought this plasma 3 days ago and have put about 12 hours on it and was noticing when there is scrolling like vertical movie credits or fast moving horizontal things the screen seems to studder a bit like its not smooth. I setup the pixel shift to 4/4/1 and figured that could be the issue but i turned that feature off for a minute and the result is the same. Is this just something I will have to deal with as it is 60hz and not like newer LCD's with 120hz refresh? ANy suggestions? thanks!
 

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I have noticed the same type of thing on my pn50b450 that I just received yesterday. I'm sure that it is not the fact that it doesn't have 120hz because that is irrelevant when it comes to plasma, but I am still not really sure what it could be.


I haven't found any type of smooth motion setting in the options or anything like that, but I definitely noticed it watching credits as you mentioned and watching some sports on TNT HD... It is quite concerning especially since I know plasmas are great for fast motion, it just seems like this one isn't as of yet...


I also have the pixel shift set to 4-4-1, but I dont see how that would affect it as the pixels only shift every minute. I ran the break-in DVD last night for about 8 hours and am yet to watch good motion content yet, so I dont know if that could have helped.


Is it possible that it is because my set is so new? (only about 15 hours on it right now) Or is it something else? Are there any known updates for this TV that might help?



Any help is appreciated...


Paul
 

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It sounds like that stuttering is caused by the 3:2 Pulldown where the set needs to convert the movie from its native 24 frames per second to the 30 frames per second supported by the TV. If the set is not particularly good at doing that you will notice some hitching on shots like horizontal pans. The only solution is to get a better TV or one that can support playing movies in their native cadence.


This would only apply to film. I don't know why you would notice it watching TNT HD.


Also, there's some confusion here between the 120Hz feature LCDs have and the speed of plasmas. Plasma manufacturers came up with a speed of 600Hz for their TVs to show consumers that plasmas have never had the blurring issues LCDs have. What you are describing is hitching or judder, not blurring.
 

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I was under the impression that the pn50b450 allows for 24p...right? doesn't that mean that the 3:2 pulldown is not necessary or is that incorrect? I thought that plasma doesn't need to worry about 60hz vs 120hz and that for lcd's 120hz eliminates the 3:2 pulldown, so do plasma's still use the 3:2 pulldown? Doesn't that make 120hz lcd better for film watching than plasma?


Regardless, I was in fact noticing this a good amount on TNT HD, which is strange...


Could someone clarify this for me please?
 

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Quote:
Originally Posted by paulster565 /forum/post/17000460


I was under the impression that the pn50b450 allows for 24p...right? doesn't that mean that the 3:2 pulldown is not necessary or is that incorrect?

I believe that is incorrect and this set does do 3:2 pulldown.


I think you should consider the possibility that the jerkiness you see is not produced by the TV set, but is present already in the source. But if you see the same effect in a variety of different sources, say TV and DVD and PS3, e.g., then that would suggest that it is indeed a defect of the TV. I have a pn50a450 and a pn42b450, but I have not yet noticed the problem that you describe.
 

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Quote:
Originally Posted by CaptainOily /forum/post/16999917


It sounds like that stuttering is caused by the 3:2 Pulldown where the set needs to convert the movie from its native 24 frames per second to the 30 frames per second supported by the TV. If the set is not particularly good at doing that you will notice some hitching on shots like horizontal pans. The only solution is to get a better TV or one that can support playing movies in their native cadence.

No...regardless of how well the TV performs 3:2 pulldown, 24Hz into 60Hz is going to result in juddering. 3:2 pulldown only maintains resolution and reduces combing/deinterlacing artifacts.

Quote:
Originally Posted by paulster565 /forum/post/17000460


I was under the impression that the pn50b450 allows for 24p...right? doesn't that mean that the 3:2 pulldown is not necessary or is that incorrect? I thought that plasma doesn't need to worry about 60hz vs 120hz and that for lcd's 120hz eliminates the 3:2 pulldown, so do plasma's still use the 3:2 pulldown? Doesn't that make 120hz lcd better for film watching than plasma?


Regardless, I was in fact noticing this a good amount on TNT HD, which is strange...


Could someone clarify this for me please?

The B450 is a 60Hz display. It will always have some judder with 24-frame (film) sources. Some plasmas are able to do shift from 60Hz to 48, 72, or 96Hz for film sources, which alleviates this problem.
 

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The name for this ability to convert 24 fps film sources to 48/72/96 hz is 24p, right? I have seen multiple sites say that this tv (pn50b450) supports 24p. Does this mean that I should be able to watch DVD's or other 24fps sources correctly without the 3:2 pulldown?


Don't get me wrong, this set looks amazing and I am certainly happy with it, but I'm just trying to get things straight.


Thanks,

Paul
 

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Quote:
Originally Posted by paulster565 /forum/post/17010606


I have seen multiple sites say that this tv (pn50b450) supports 24p. Does this mean that I should be able to watch DVD's or other 24fps sources correctly without the 3:2 pulldown?

It does support 24p, but it does so by using 3:2 pulldown, I think. Since it does 600Hz, and 600 is an integral multiple of 24, there's no fundamental reason why it couldn't give equal time to each of 24 frames per second, but so far as I know, it just doesn't do that. I have no means, personally, of comparing 24p done "right" and done with 3:2 pulldown, but some say they can't tell the difference.
 

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Well from what I have gathered, the 600hz cannot be referenced like that, by saying that it is a multiple of 24, because the 600hz subfield motion is not the same as, for example, an lcd's 120hz refresh rate, but that still leaves me wondering what exactly 24p does...
 

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The 600Hz marketing malarkey refers to the temporal dithering speed plasmas use to produce gradations of light and color. Its related to refresh rate in a sense, but not in a way that's a useful in comparison to LCD refresh rate.


"24p" is more or less a format/signal standard that refers to blu-ray players' ability to output 1920x1080 at 24Hz. The B450 no doubt "supports" 24p in the sense that it will accept the signal, but it will always do 3:2 pulldown (if it recognizes film cadence properly) and display the source at 60Hz.


Not to be rude, but it would serve you well to do some searches and basic reading of prior posts. There is a ton of information on this stuff here on the forum and elsewhere online. 600Hz is mostly marketing crap. 24p is mostly marketing crap, except when fully supported by all your gear.


If you feel you need 3:3 (72Hz) or 5:5 (120Hz) pulldown, there are plenty of sets out there that will do that. AFAIK, no plasmas do 120Hz at this point, but 72Hz is plenty and the Automotion Plus and similar technologies that LCDs employ to interpolate frames is also a bit of a gimmick, in my opinion.


Also, I would recommend you stay away from plasmas that do 2:2 pulldown and display film sources at 48Hz (only the Panasonic G10 series does this, that I'm aware of). I have not seen an implementation of this that didn't produce flickering due to the low refresh rate.


A final note, some forum members have stated that all the 2009 Panasonics employ a low-level frame interpolation scheme. I can't confirm or deny this, but if true, I believe it might reduce film judder to a degree, even at 60Hz. Would anyone care to chime in if you're in the know on this topic?
 

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Quote:
Originally Posted by Noah /forum/post/17011137


A final note, some forum members have stated that all the 2009 Panasonics employ a low-level frame interpolation scheme. I can't confirm or deny this, but if true, I believe it might reduce film judder to a degree, even at 60Hz. Would anyone care to chime in if you're in the know on this topic?

I would also like to know about this. If there is less judder on the Panasonics, I may go for the P50X1/50PX14 instead.
 
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