Plasma TV is 1024x768, how does it do 720p?

Columbo

Columbo

Columbo

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I have a Panasonic TH-42PX80B Plasma, now I have been watching my stuff through a Popcorn Hour A-110 and basically just set the output of that to 720p and all is good.

However I'm now building a HTPC to replace it as I'd like to have more of the functionality a PC has to offer + Vista Media Centre.

Theres one thing I dont get however and that is my TV has a resolution of 1024x768 yet 720p material is 1280x720. How do I get it to display properly?

1024x768 is a 4:3 ratio is it not? Can I somehow force my TV do a res of 1024x720 (16:9). As it does not give me the option in display settings?

I've tried various sources of info but cant find a definitive answer.

TBH I should have done my homework a little better but I do feel a little duped by the manufacturer on this.
 
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You answered your own question :P it's because it has a Pixel Mapping of 4:3. Therefore you can't change it I'm afraid.

It's "HD Ready" so whilst it can display 720p images, it doesn't display them "well". This is why they had to add the term "HD Ready 720p" and "HD Ready 1080p". Newer, modern sets come with 1:1 ratios so therefore they can display the proper resolutions.
 
Locke said:
You answered your own question :P it's because it has a Pixel Mapping of 4:3. Therefore you can't change it I'm afraid.

It's "HD Ready" so whilst it can display 720p images, it doesn't display them "well". This is why they had to add the term "HD Ready 720p" and "HD Ready 1080p". Newer, modern sets come with 1:1 ratios so therefore they can display the proper resolutions.
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I disagree that they dont look good. (Check some reviews on this set) The picture quality from my A-110 is stunning and competes with sets vastly more expensive that do higher resolutions.

Ultimately I suppose I'm just looking for what settings to use to get it to display properly.
 
it will display properly. it might have a 4:3 ratio of pixels but they are rectangular pixels with 16:9 dimentions........in other words if you feed the tv a 16:9 signal it will display in the correct aspect regardless if its native resolution. if you (do manage to) send the tv 1028x768, it would actually be stretched out of proportion becuase of those rectangular pixels.

you're also talking about one of the best ~40" sets around, which should you feel duped? its about the final image at the end of the day, not how it gets there:)
 
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james.miller said:
it will display properly. it might have a 4:3 ratio of pixels but they are rectangular pixels with 16:9 dimentions........in other words if you feed the tv a 16:9 signal it will display in the correct aspect regardless if its native resolution. if you (do manage to) send the tv 1028x768, it would actually be stretched out of proportion becuase of those rectangular pixels
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Superb mate, exactly the answer I was looking for. I was presuming that all the pixels were square. But it now makes sense to me.

Cheers buddy..!!
 
You can feed it a 4:3 signal and adjust your AR in software to compensate for the stretched-ness. Kind like pressing the 16:9 button on a 4:3 TV when feeding it a 16:9 signal. (i.e. you use the whole height of the picture but squash it in horizontally) Most decent media players have an option exactly for this.

Or you can just feed it a 1280x720 image in the first place, which I must admit looks absolutely stunning as well.
 
Well technically it's called 768p as it is 768 Horizontal line progressive signal.

Tvs display them very well, especially the 1024x768 42 Kuro that is still the best 42inch flat panel out there by a good, and it has even been discontinued. THose who have owned one or still own one will agree with me on this, especially Asprilla.

Don't worry about the technicalites or number of pixels, the picture seen by your eyes is the most important.


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Thanks for pointing out my slight error, it's horizontal lines.

Well just think of it as the opposite of an interlaced signal. See a 1080i signal is only 540 lines of actual resolution as an interlaced signal is split into x2 540 line signals, with each one being every other line, then the 2nd one being all the missing lines. Only one is showed at a time, but then the 2nd one is needed to fill in the alternate gaps so the tv flicks between the 2 very fast. A progressive signal contains every line of a picture thus actually has 768 lines (technical term of 768 lines as resolution is 1024x768). I may have confused myself there, as it will be 768 horizontal lines, woops my bad.

That is why a 720p signal is actually better compared to a 1080i signal which only has 540 horizontal lines on display at any one time. it just cycles between them very quickly so the eye can't see. But it can actually be seen on some sets when there is a fast moving image such as a football being kicked where you will see a smearing effect across the screen. This is where plasmas can handle the motion better than LCDs :D

Type in 1080i or 720p into youtube and there will be a video that can explain it better for you if you need some video/pictorial footage.
 
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-Ad- said:
Thanks for pointing out my slight error, it's horizontal lines.

Well just think of it as the opposite of an interlaced signal. See a 1080i signal is only 540 lines of actual resolution as an interlaced signal is split into x2 540 line signals, with each one being every other line, then the 2nd one being all the missing lines. Only one is showed at a time, but then the 2nd one is needed to fill in the alternate gaps so the tv flicks between the 2 very fast. A progressive signal contains every line of a picture thus actually has 768 lines (technical term of 768 lines as resolution is 1024x768). I may have confused myself there, as it will be 768 horizontal lines, woops my bad.

That is why a 720p signal is actually better compared to a 1080i signal which only has 540 horizontal lines on display at any one time. it just cycles between them very quickly so the eye can't see. But it can actually be seen on some sets when there is a fast moving image such as a football being kicked where you will see a smearing effect across the screen. This is where plasmas can handle the motion better than LCDs :D

Type in 1080i or 720p into youtube and there will be a video that can explain it better for you if you need some video/pictorial footage.
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I'm not sure how any of that is relavent to the above discussion, however I think you may be confused (or just not explaing very well)

A 1080i signal has more lines than a 720p signal, 1080 lines in fact. It's just that as you say only 540 are visible at once.

i'm not sure where you ar getting 768 progressive signal from... A HD signal will have 720 lines of resolution. (or 1080) The display device may have 768 lines, but this is completely unrelated to the signal, unless you feed a signal from a PC (say) that is outputting a 768 line high res, usually 1024x768 or 1366x768. This is why 720 sets will always scale the image. I'm sure this was done to death in the Blu ray on 720p thread the other week. (here: http://forums.overclockers.co.uk/showthread.php?t=17945144 )
 
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whitecrook said:
I'm not sure how any of that is relavent to the above discussion, however I think you may be confused (or just not explaing very well)

A 1080i signal has more lines than a 720p signal, 1080 lines in fact. It's just that as you say only 540 are visible at once.

i'm not sure where you ar getting 768 progressive signal from... A HD signal will have 720 lines of resolution. (or 1080) The display device may have 768 lines, but this is completely unrelated to the signal, unless you feed a signal from a PC (say) that is outputting a 768 line high res, usually 1024x768 or 1366x768. This is why 720 sets will always scale the image. I'm sure this was done to death in the Blu ray on 720p thread the other week. (here: http://forums.overclockers.co.uk/showthread.php?t=17945144 )
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Hey

Yup sorry I kept saying 768p signal which is totally wrong, I was talking about the output of the tvs with their 768 horizontal lines. Signal wise of course being:

720p = 1280x720
1080p = 1920x1080

The difference in resolution between some LCDs (1366x768) and plasmas (1024x768) is because of their respective pixel shapes, rectangular or square.

Think it was mentioned in that thread, but obviously tvs will have to scale the 720p feed as I don't know of any sets with that res, but 1080p sets have the 1920x1080 res.

This subject is a bit bonkers, especially when setting up the set with different source equipment and footage. E.g. My PS3 is setup to upscale dvds to 1080i which is fed to the tv which then de-interlaces the signal to get a 1080p. Don't know why that is the best with more steps, but bumtious at avforums recommended it for the best PQ, I can only guess becuase the Kuro probbaly does a better job de-interlacing than the PS3.
 
Yes, and with plasmas it's like a CRT - the 1024x768 ones will display that optimally, but they don't really have a problem displaying 720 or other resolutions (within reason) becuase of the makeup of the picture. LCDs on the other hand just don't do displaying at non native res very well at all IMO.
 
whitecrook said:
Yes, and with plasmas it's like a CRT - the 1024x768 ones will display that optimally, but they don't really have a problem displaying 720 or other resolutions (within reason) becuase of the makeup of the picture. LCDs on the other hand just don't do displaying at non native res very well at all IMO.
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:D Don't get me started on LCDs, they have a purpose as a gaming screen / monitor, or use in bright environments........ Anything else is for another thread :D
 
Actually, plasma vs LCD and 1080p vs 720p arguments aside, one of the things that attracted me to a 1080p panel was the ease of driving it from a PC. I've tried driving several 720p plasmas from a PC, including a PX80, and it was a total nightmare trying to get it doing proper 1:1 pixel mapping.

Not sure why but I've seen quite a few posts from people having this kind of trouble. PC graphics cards seem to need a lot more coercing to drive a screen at 1024x768 or 1366x768 than they do 1920x1080.
 
The CEA standards don't include your horizonital res. for the 720p standed, it is and was common for DLPs, Plasmas, etc to have 1024x720(720+) and not the full 1280x.

On a 720p/1080i LCD that is native to 1366x768 screen you are usually better with the 720p. A little upscaling will occur on 720p rather than have the whole 1920x1080 taken down to native. The upside is you'll get >30 fps on a 1080i instead of a 720p which would be >60fps (assuming 60hz) ...

... and no damn interlacing artifacts!!
 
Just like to add for anyone interested that I'm now feeding my TV a 1280x720p signal from the HTPC I've built and it looks fine.

Not sure on what scaling is going on but all I know is that it displays in the correct ratio. Picture quality is stunning as well.

Very surprised as Im only using an AM2 780G mobo with on-board HDMI, great purchase for the money.
 
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