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Ok, first of all I would liek to say a big "HELLO" to all of you since this is my first post in this forum.

Now a little bit about me. Basically I know everything about PCs but very few stuff on Audio-Video. But at the moment I am about to make a big step and stop wasting my time and money so much on PCs and invest on an HDTV setup to accompany me on my free time because I am a movie lover.


Now, I haven't fully understood al this 720p, 1080i 1080p things. In order to understand stuff I try to translate them in PC terms which I am most familiar with. As I understand, 720p stands for 1280x720 proggresive, 1080i for 1920x1080 interlaced and 1080p for 1920x1080 proggresive. However I can't understand what the difference between proggressive and interlaces is....and how do people compare 720p with 1080i.....in computer terms comparing 2 completely different resolutions is out of the question....and even more, I have seen people say 720p isalmost the same as 1080i....how the hell can 2 completely different resolutions be the same? ehat is this interlaces/progresive thingy that makes those comparable?


My next question is this: Lets say you know that you will mostly view HD signals of 720p. Why so many sets in the market have screens of 1366x768 or 1280x768 ? Supposedly a higher resolution is better (in computer world) but since the signal of 720p will be scaled to fir 1366x768, wont you have a worse result than a native 1280x720 screen that will not scale at all? Thats how I think of it in computer world where you are supposed to use TFT screens on their native res for best results (after all they are not CRTs that can view each resolution equally). If I am right on this, when going for such a TV for 720p , you should opt for 1280x720 and not 1366x768 or 1280x768 for best results right?


Next thing. I have taken a look in 27" LCD-TVs and there is a great margin in prices. There sre screens starting from 850 euros and ramping up to 1800 euros....sometimes even from the same manufacturer. I tried to see the differences in specs, but since I am a computer guy, from my experience with TFT screend I only see the resolution and the signal Inputs. In both these prices they were the same. In a computer screen I would look for the panel type too (TN+film, SIPS, SMVA/SPVA) but I couldnt find this info on those screens.....is this the difference or something else I am missing? Or its just a matter of design?


I got many more questiong but I feel I have already bombed you with lots of stuff, so I will keep them for later....help me plz get into this world and make the right purchase for myself.
 

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Welcome to the forums. Too big a topic, IMO, to summarize in a post. But I'd suggest. as a start, skimming through the sublinked article in this HD resolution summary where consultant Michael Robin outlines the 720p format and mentions, near the end, an important difference between computer and sampled video signals. -- John
 

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As far as the programming goes, HDTV comes as 720p or 1080i and you don't have a choice for any given program.


Although you may notice regularly spaced irregularities when you use a display with a different resolution than the source material for computer usage, the problems with a 1366x768 TV for 1280x720 (or even 1080i 1920x1080) are not obtrusive in TV shows.


If you buy a TV with approximately 1280x720 resolution it should have a 720p input. If you buy a TV with approximately (anything)x1080 non-interlaced resolution it should have a 1080p input. Otherwise you will be unable to upgrade the scaling if you should want to at a later date.


TV specs. don't emphasize things like TFT or TN-film but rather talk about things like contrast ratio and decay rate. Some of the screen technologies are not usable for TV video applications because of a too slow decay rate, moving subjects look smeared.


Video hints:
http://members.aol.com/ajaynejr/hdtvnot.htm
 

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As far as interlaced versus progressive scan, in the old days of TV all signals were interlaced. One screen of picture is called a Frame. Using Interlaced scanning the Frame is made of 2 parts called Fields. Half of the scan lines are drawn in the first Field top to bottom. Then the Raster (scanning Beam) moves back to the top of the screen and draws the second field completing the frame. In the old days this was fine. Because of the smaller size of screen coupled with the image retention of the eye the retrace lines were not seen and it appeared as one complete frame.


With the introduction of very big screens the retrace lines became more noticable as well as video artifacts hence progressive scan which draws the sreen in only one frame not 2 fileds making the picture considerably clearer. In 720P there are basically 720 lines on the screen at one time. In 1080i there are 540 lines on the screen at one time so it is really more equivalent to 540p but due to image retention of the eye you may not see the difference between it and 720p. Hope that helps.
 
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