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Help me untangle the HDTV technical gobbledygook

by Lee Koo (ADMIN) CNET staff/forum admin / July 12, 2007 9:45 AM PDT
Question:

I keep getting bombarded with ads about HDTV. When I go to a store that carries them (for example, Best Buy or Costco) I find that the clerks really don't know much about them. I came across one that looks interesting, but the description is nothing if not confusing. Perhaps someone can help me untangle the technical gobbledygook. For example: the set I was looking at is a 42-inch HD LCD set with a resolution of 1,920x1,080. It is compatible with 480i, 480p, 720p, 1080i, and 1080p. I think i means interlaced (like my analog TV set) and p means progressive. What is the significance of these designations, as a practical matter? Is i or p defined by the TV station or is that a choice of the receiver? It is said to be compatible to NTSC (I recognize that), ATSC, and QAM (what are these?), and are there other systems out there that need to be covered? What is Media Connectivity? Someone needs to publish a document that ordinary mortals can read and understand. Any suggestions?

Submitted by: Nat C.

This answer was voted most helpful by our community members

Answer:

De-Mystifying HDTV

Wow! A Lot of questions! Let's start by looking at those confusing HDTV definitions and then we'll look at how the signals are received from your DVD player or Cable box.

Basic, old fashioned TV (the kind you might have bunny ear antennas behind) are 480i. The 480 means that there are 480 lines of "light" hitting the screen of your TV from behind (counting from bottom to top). Now let's call the very bottom-most line, line 1, the one above line 2 and so on, okay?

The i indictor, you are quite right, means "interlaced". The problem with old analogue TV signals is that they can't carry very much data at one time (they have a small "bandwidth"), which makes it difficult to reliably get 480 lines of data to your TV at once. Instead, they actually only broadcast half of the signal, (lines 1, 3, 5, etc) and then right after that the other half (line 2, 4, 6 etc) in a separate transmission. If your TV keeps alternating the picture between odd and even lines fast enough, you don't see much of a difference. It is therefore ?interlacing? the two separate pictures of 240 line each.

naturally this means that the other type of indicator, p (which stands for progressive), simply means that the device is showing you all of the lines all of the time. That is to say instead of updating lines 1, 3, 5 and then 2, 4, 6, it updates 1, 2, 3, 4, 5, 6, which makes for a much smoother looking picture, especially when your are watching something with a lot of fast movement like an action movie.

The screen resolution will also tell you the number of lines on the TV screen (in your example of 1920 x 1080 this would be a resolution of 1080 lines).

There are three "defintions" for TV types, Standard Definition (SD), Enhanced Definition (ED) and High Definition (HD). SD simply means 480i (480 lines, not all shown at once). ED means 480p (480 lines, all seen at once). You will very rarely see ED as a TV feature anymore, and I think most people on this board would strongly recommend against even looking at an ED set. So, anything that's left (anything with more than 480 lines) is considered HD.

Therefore because progressive is the best way to deliver a signal and 1080 lines is the highest number of lines in use today, a 1080p TV will future proof you and provide the highest quality picture options. These are getting so cheap now that unless you are looking for a real budget unit I wouldn't buy anything else.

For a long time LCD and Plasma HDTVs only came in 720p (unless you had LOTS of money to burn), but more and more 1080p sets are now out there, and at very reasonable prices, almost all projection TVs produced new now are 1080p.

Now let's move onto how we get that HD picture to your TV. Just like music, your picture quality will only be as good as your weakest component. If you are listening to an old audio cassette, it doesn't make much difference how expensive your sound setup is, you are not going to get great quality music. The same is true of TV.

People generally get their TV one of 3 ways, Cable, Satellite or the Free over-the-air kind.

All of these ways of receiving TV offer HD content (they broadcast a digital signal that can carry HD information, separate to the analogue signal that older TVs pick up). Most cable and sat providers can rent you an "HD Box" that will allow you access their HD content.

They may broadcast some shows in 720 lines, but most now come in 1080i. You should beware that in order to "save space" both cable and satellite providers compress their HD signals. Decompressing these signals for you to see is what their "HD Box" is doing (just like ZIPing a computer file). You will inevitably lose some picture quality due to this compression process but for most people the difference is minimal. Just a side note, an HD satellite signal is typically less heavily compressed than its cable cousin.

You can watch a 1080 signal on a 480 digital set if you want but you will of course lose some of the detail. Likewise, you can watch a 480 broadcast on a 1080 set. In this case your TV actually has a small "brain" inside it, which creates new lines to make a full 1080 image (it looks at the colors above and below the line it is creating and guesses what should go in the middle). This process is called "up-scaling". If you are going to be watching a lot of regular DVDs (which are in 480p as long as you have a "Progressive Scan" DVD player) then how well the TV up-converts should be a key question you want answered before you buy.

You don?t need to worry at all about NTSC versus ATSC versus QAM. NTSC is the name given to the way US broadcasts manage color in the picture. ATSC is simply the name of the council of people who set the rules for HDTV (so that you can buy any brand HDTV and it will work with any HD signal) and QAM is simply a way to modulate the signal to fit more data into the same signal. All HDTVs will use QAM and comply with ATSC?.

Finally your question on "Media Connectivity". This simply means it has a lot of plugs in the back and front... that's it. It means you can connect it to a standard digital connection with a Digital Coax Cable, or through an HDMI cable or to a computer with DVI etc. Often you can plug a USB thumb drive or your digital camera?s memory card right into the TV to view pictures on them as well....

Although 1080p sets can play up to 1080p signals, there are no broadcasts out there in any definition better than 1080i right now (and due to bandwidth restrictions, there won?t be for some time yet). However your 1080p ability comes into play with the new High Definition DVD formats (HD DVD and Blu Ray DVD). These both send out a 1080p signal, for the best picture quality possible.

In short, when you are in the store, look at any 1080p TV. If you are looking at it in a store try to see if they can show you a standard 480 signal on it as well as HD to see how it handles both types of signal.

I hope this helps!

http://forums.cnet.com/5208-10149_102-0.html?forumID=7&threadID=256144&messageID=2539809#2539809

Submitted by: gingaskunk

If you have additional advice for Nat, let's hear them! Click on the "Reply" link to post. Please be detailed as possible in your answer. Thanks!
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answers
by Mike MacFarlane / July 13, 2007 1:17 PM PDT

the you got the i and p correct. with interlancing it puts out every other line per sweep where as progressive puts out every single line. progresive is good for fast action. most Satilite receivers and cable boxes are 720p or 1080i where as HDDVD Blu-ray players are 1080P compatible. NTSC is used in North America the rest are in different countries (why some dvds you buy in Europe wont play on your dvd player)

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Explaining HDTV terms
by mrpaul / July 13, 2007 1:30 PM PDT

Interlaced signals are sent by CBS and NBC. First the 1's are sent and then the O's are sent, they "interlace" (get together) and form the signal. 480I is standard definition, 1080I is high definition. ABC and FOX for example send 720 1's and O's all at once (progressive scan) 720P for high def. The human eye cannot see the difference in 1080I and 720P. A regular cable or satelite broadcast is 480I in standard definition, while a regular DVD is 480P, which is why a DVD looks a lot better than standard television. NTSC is the old broadcast standards for analog tv, while ATSC is the standard for digital TV signals. A QAM tuner in a TV can decode and play the signals from coded cable if the TV has a "Cable Card" inserted from the cable company. 1080P is that many lines of resolution put on the screen all at once from a Blue Ray 1080P DVD Player playing a disc recorded in that format. More lines displayed all at once means better clarity and richness of all the colors on the tv. No broadcast signal today is broadcast in 1080P, only from a blue ray dvd player. It may be years till the broadcast industry transmits a 1080P signal. A 1080P tv does not make regular HD signals any better than a 720P/1080I signal. All of todays HD tv's automatically decode whichever type of signal is received.

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Re:HDTV
by NickMorgan / July 13, 2007 1:41 PM PDT

The only thing I can tell you is this: The standard analog tv signals are scheduled to be totally stopped as of Feb. 2009. If you don't have a digital tuner in your tv you will not be able to receive any tv stations (unless you buy a converter).

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Won't effect TV's hooked to satellite or cable...
by Hi-def Jeff / July 15, 2007 8:00 AM PDT
In reply to: Re:HDTV

The only TV's that will lose signal are those that are using an antenna. The great part is that if you're using an antenna, an HDTV with digital tuner, or conversion box, will substantially increase your viewing. Your picture quality will be crystal clear, like satellite, and you will likely add to your High Definition content, and get more local channels from those that are "multi-casting". Local broadcasters now have the ability to send more than one "channel". For example, St. Louis PBS sends 4, now. 9-1 is all HD, 9-2 is all kids, 9-3 is what's broadcast analog, and 9-4 is the Create channel.

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St. Louis Television
by sojournerwolf / July 27, 2007 8:38 PM PDT

Thank you, Hi-def Jeff; I did not know about the 4 channels of PBS in St. Louis.

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Want more?
by Hi-def Jeff / July 28, 2007 3:01 AM PDT
In reply to: St. Louis Television

There's more too! Music on 11-2, weather on 5-2, and more to come.

Check out this page for all of your HDTV answers whatever city you are in, including DTV broadcasts.

http://www.wowvision.tv/answers.htm

Happy HD Hunting!
Highdef Jeff

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Re:HDTV pocket portables
by amckenas / July 20, 2007 10:24 PM PDT
In reply to: Re:HDTV

I have a 3 inch 'pocket' TV. Will I have to carry around a 4 pound converter too? Or should I just throw the tv in the trash?

I hope new 'pocket' TVs will be compatible!

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Decrypting HDTV
by orbital318 / July 13, 2007 2:02 PM PDT

Nat C. True HD Resolution comes in 4 flavors. 720i, 720p, 1080i and 1080p. The 720s represent pixel dimensions that are 720x1280 and the 1080's are represented by 1080x1920. The letter "p" and "i" represent 2 things frame rate and interlacing. Interlaced video is always 30 frames per second (29.97 fpr NTCS) and has 2 fields per frame or 60 fields per second. These fields are developed from scan lines which represent every other line. All you need to know though is interlacing, because of the fields is more akin to a little better than the progressive resolution below it. So 1080i is similar though slightly better than 720p. That is why most 720p TVs also support 1080i resolution. Now regrading 480i and 480p those are what are called Standard Definition or DVD resolution.

From a practical standpoint. 1080p is the best, but you only really need to buy a tv with that high resolution if you intend to buy a Blue Ray or HD DVD player. Both will display 1080p, otherwise nothing else (other than a PS3 and an XBOX 360) will display 1080p. TV shows via cable or ATSC (I'll get into that next) are always 1080i, 720p, or a Standard Definition. The TV station chooses to broadcast at what ever the resolutions they decide. The Tuners NTSC ATSC and QAM, all are differnent animals. NTSC is the "standard" over the air signals. Like the ones you get with rabbit ears. Interestingly enough, they now have ATSC tuners which also use rabbit ears, but they can receive and HD signal (for free of you local channels). So both of those tune signals from the "air waves" like NTSC. QAM tuning is the ability for your TV to accept a cable signal without a settop box. If you don't have NTSC and ATSC tuners you may not beable to get a signal from the cable box either.

Media Connectivity usually refers to the multitude of connections that your TV can have, like multiple HDMI ports(what you use to connect HD devices to your TV) as well as computer VGA ports so you can use your tv as a monitor.

I hope this covers everything.

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orbital318...one note on the xbox360
by tadzilla / July 21, 2007 12:25 AM PDT
In reply to: Decrypting HDTV

the xbox, tho it DOES offer a an HD-DVD add on, the xbox does NOT have the cable connection ports to shoot out the HD signal to your tv...so i think the max the 360 can do is 480p.

*** i am not sure about the xbox 360 extreme, or whatever it is called...the version where the HD DVD drive comes pre-installed in the 360. im not sure if they added the cable connections to send the HD signal to your tv.

yay for ps3 =)

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Xbox 360
by LitTehWin / July 30, 2007 12:00 PM PDT

The Xbox 360 is capable of 720p and 1080i via the HD Component cables (red, blue, & green). My sony lcd shows the resolution in the top left corner when I switch sources. There is, however a switch on the end of the component cable (the end going into the 360)that must be switched to HD in order to recieve the high resolution output.

Yay 360.
Boo $500 for ps3. I would like one though. Sad
Can I has urs? Grin

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Short Answer: Take a class!
by 4Denise / July 13, 2007 2:36 PM PDT

Once again, there are a lot of people in the CNET community that are better qualified than I to answer this question, but there actually are free internet classes on this very subject! You are far from the only one who hasn't memorized all of this junk. After all, we all have to devote some of our brains to living normal lives.

Try CNET classes:

http://classes.cnet.com/?tag=navtab

and HP online classes (you don't need to own HP equipment to take them):

http://h30240.www3.hp.com/index.jsp

And you can try typing "free online classes" into your favorite search engine to see what comes up.

Such classes are usually a week or two in duration and they give you a lot of decent information, as well as providing you with a forum to discuss the matter with others taking the class, probably for exactly the same reason you are.

4denise

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Understanding flat panels
by Toonsdad / July 13, 2007 4:41 PM PDT

The most important thing to look at when selecting a flat panel is the refresh rate. Not all flat panels are equal, LCD or Plasma. A tube ( or CRT) still has a way bigger advantage over both of these. This is important because if you watch Nascar, or action movies, you will notice a blurr behind a fast moving object on the screen with a flat panel, but not with a tube type. Unfortunately you can't buy a very large tube type TV that is 1080P anymore. I have one of the last ones Sony made, they don't do tubes anymore.

The second most important thing to ask for is HDMI. HDMI is a type of connection for your Hidef set. If you have cable or a dish, odds are good there is an HDMI connection on your box. This type of connection is good because it will cut down on the number of cables running behind your set. Also most video cards for your computer have this connection too, allowing you to connect to your computer and watch stuff off the internet.

If you go into a store and start asking about refresh rates, HDMI, and price, pretty much in that order, you will soon see what you can and can not afford. Then do your shopping from there.

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Specifications for HDTV Systems
by news4la / July 13, 2007 5:35 PM PDT

There are 18 different systems in HDTV. The ATSC is the digital equivalent of NTSC. That is the group that makes all the rules. I am not sure of QAM. I think it is a way of modulating the signal. It might have something to do with cable specs. Interlaced is sending all odd numbered lines then sending even numbered lines.(2 to 1 interlace) Progressive sends the lines from begining to end without reguard to the number. In my opinion I like progressive because of its lack of flicker. It is also used in computer monitors.So a set with 1080p is an excellent set. If only TV stations would work on the quality of their waveform things would be fine.Make sure the set has HDMI connections.(High Definition Multimedia Interface) Now there's a mouthful. I hope this answers your questions.Good luck with your purchase and ENJOY yourself.

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HD TV!
by Jelly Baby / July 13, 2007 6:53 PM PDT

Maybe I'm missing something here - but why are you asking about TV on a computer forum?

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Where does it say it is a computer forum?
by Lee Koo (ADMIN) CNET staff/forum admin / July 20, 2007 5:16 AM PDT
In reply to: HD TV!

While I do agree that most of our forums consist of computer related topics, please do take a look at the forum categories here:

http://forums.cnet.com

and you'll realize that the CNET forums are not specific to only computer, but technology--which cover topics such as digital cameras, cell phones, TVs, and so fourth...

Hope this clarifies things.

Cheers!
-Lee

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extended warranties
by jrenjr / July 21, 2007 3:29 AM PDT
In reply to: HD TV!

Save your money. If you buy from a major manufacturer you will have no problems. 95% of the gliches will show up in the first few months;or none at all. I wasted $400. on my first HD tv from Hitachi. The set is a CRT projection TV and is 5 yrs old and not one problem. You can save the money for when you want to upgrade in 3 or 4 yrs. or buy a HD DVD player.

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Now it?s all explained.
by crog_bad / July 13, 2007 7:51 PM PDT

Ok, lets start with the resolutions/outputs.
480i, 480p, 720p, 1080i, and 1080p all refer to the second half (the smaller number) of the resolution, so both 1080i and 1080p would display the resolution 1,920x1,080.
P. vs. I.
As you quite rightly said before P stands for progressive and I for Interlaced.
With I, the image is made up of horizontal lines, these lines are then dived by two (ever other, not top and bottom) and the information for these lines is spread over two frames of the video, this saves on storage space, and makes is easier on broadcasting companies, but with decoding of the interlaced video or fast moving scenes you'll see the horizontal lines.
Progressive scan on the other hand, each frame has a complete image which it displays, this more powerful hardware to display it without stutters and requires a lot more storage space, but the image is always good.
Compatibility: You said its compatible with NTSC, if your from the USA then that?s fine, don't worry about the others because everything you play will be encoded in NTSC.
Media Connectivity: is quite simply a word used to say the input jacks on the rear and side or front panels. Nowadays with HDTV's there?s a lot more connections to think about. There?s you old S-Video, Scart, and RGB, these are fine for standard definition video. However for HD video you'll need to use, HDMI, Component, (VGA, DVI these two are PC connectors). HDMI is one large plug (much smaller than Scart though) this will provide the best in video quality allowing you to watch in full 1080p with any interference as it is digital. Component has 5 jacks, 2 for sound and 3 for the image, i believe this will only allow for 1080i but i am not sure, and as the signal is apologue you may pick up interference.

And now for one other thing you may need to know but did not ask.

Contrast ratio: This is quite simply how black the blacks are and how white the whites are. So the higher the ratio the better the image. 1:500 no thanks, 1:3,000 yes please.

I hope this helps and, have fun with your new TV when you buy it.

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HDTV Ad's (and the confusing features of HDTV)

Hello Nat

I live in the UK and this is my first posting on this forum.

I have also just bought a new 32" Philips HD LCD TV, which unfortunately is not as good as the one you were looking at as it is not '1080p' nor does it have anything like the number of pixels or screen size.

My answer is a bit long but I hope it helps

In relation to your question, 'Media Connectivity' is not a term I have heard used here. I would assume it would be something to do with connecting to media, in other words connecting to media devices e.g. DVD players/recorders, vcr's, computers, and game consoles - Microsoft XBOX or XBOX 360, Sony Playstation - camcorders, etc. using either the red, yellow and white phono cables, scart, rgb(component), or hdmi cables or whatever other connectors BOTH TV AND DEVICE would have to have.

The terms NTSC refers to a technological format used by the US TV broadcaster i.e. in the UK our TV is broadcast in PAL, Japan uses SECAM?, USA uses NTSC. This is also the same for anything 'recorded' in these countries e.g. if you recorded some tv at home in the US then took the vhs tape with you to some freinds or relatives in the UK or japan it would NOT display properly if at all in their VCR, and also if you brought a vcr and/or tv with you from the USA that also would not work even if you had an adaptor for the different electrical plug that the US uses, though some TV's like my old one can switch the from NTSC to PAL and vice versa, ascould my old vcr but hy are both now worn out. Just how this would relate, if at all, to the presently available and the new and upcoming HD (and blu ray) DVD players/recorders, I don't know.

You should also be aware, if you are not already, that the US and other countries all use 'region coding' technology in DVD PLAYERS, Recorders and games consoles, and on the PRE-RECORDED DVD's and games that they use in them, that is supposed to prevent people in the UK and other countries from getting their hands on movies and games that are released on DVD in the US, before those movies are even released to the Cinemas/Stores here in the UK. e.g. UK has 'region 1' so DVD's from US will have a different region coding initially, until the film studios decide to release versions that UK and other countries DVD players and games consoles, can play. To get round that you could always look for a player that is 'multi region' coded. The same will also be true for pc's, I expect that can play games and play/record onto DVD.

As for ATSC, QAM, (and 'i' and 'p'), as well as the difference between them and what they actually mean, I have no idea, as I have never heard of these terms, but if they are in the same location on a card showing the details/features of a TV (that you ARE familiar with or the assistant has heard of one of the terms quoted), then would also assume them to be refering to something similar, i.e ATSC and QAM would be some other broadcast format and the relevance of 'i' and 'p' would be connected with picture quality. I think if the 'p' means progressive it could be refering to something like 'progressive scan' which is something used by higher quality vcr's to improve the image from analogue vhs tapes, so how it relates to a HD TV I am not sure but it might be related. The 1920x1080 refers to the number of pixels that are used to make up the image on the screen, therefore the more the better, just the same as it is with computer monitors (which your new HD LCD TV will be able to be used for, if it AND the pc has the same and correct type of connectors) and digital cameras/camcorders.

Also a lot of features on these and older tv's may be useful as away of gauging quality, but like you said you don't know whether they are defined by the TV or the broadcaster. All of the features you mentioned are inherent in the TV's, but to make use of some of them like High Definition or Digital the broadcaster has to be broadcasting their content in high definition and/or digital.

In the UK our choices are terrestrial analogue TV (or terrestrial digital which uses a different kind of tuner/receiver NOT found in VCR's and older CRT tv's) through an aerial or digital only via a digital 'cable' receiver/decoder or fixed satellite dish and receiver/decoder. Only the 'Satellite TV' company here currently broadcasts any 'High Definition' content - which is more expensive than 'ordinary digital' - on a low number of channels, so currently we have no real 'need' of 1080p at the moment.

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HDTV & LCD
by Stevenstcroix / July 13, 2007 10:21 PM PDT

From my lateral annalistic view of HDTV, one thing I do have some knowledge of, is that any type of High Definition Plasma, TV or otherwise, which incorporates LCD, will not give the highest quality unless the TV is designed to stabilize the moving Liquid Crystal Diode function, not apparent in all LCD consumer electronic products. TFT however, I think has a much more stabilized pixalization and the crystals do not move barely at all unlike the LCD crystals. This option of TFT I would recommend in whatever you decide to purchase. And yes, I agree about some confusing issues as to 'what is what'.
The TV your referring too probably has different scanning options too like Progressive and 100MHz etc. which you can change according to your preferred requirements. I hope this information will be of some use to you. Kind Regards, Steven.

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Response time and Contrat ratio
by jtpxxx / July 21, 2007 5:10 AM PDT
In reply to: HDTV & LCD

These are two of the most confusing and abused of the TV specifications.
Motion Response time --
Old CRT TV's (cathode ray tube) had a beam scanned across the face of the tube. Each pixel would be excited by the beam, glow for a short time ( a few milliseconds, the decay time) and wait for the next time the beam would come by to glow again. The ration of time dark to time bright (duty cycle) was maybe 10% bright to 90% dark. Our brain would fill in the gaps and the motion response appeared smooth to us.

Plasmas have more time that the pixel is on in a series of pulses and are a little worse than CRT TV's but usually not objectionable.

LCD TV's have essentially 100% on time and so we process the steps between each pixel to the next a smear in the image. This smearing has nothing to do with the response time of the LCD pixels to get to the right level, it's the fact that they stay at the same level for the whole period until they are changed by the next frame of the movie.The fact that the LCD changes slower is actually a minor contributor to the smear in modern sets since the actual LCD responses in new sets are fast enough. New LCDs attack the smear by changing the pixel twice as fast (120Hz) and/or by blinking the backlight to lower the duty cycle.

A measurement of this smear is called the Motion Picture Response Time (MPRT) and is about 2 milliseconds (ms) in a CRT, 8ms in PDP,
12ms. in a cheap LCD, 8ms in a 120Hz LCD, and 4ms in a 120Hz LCD plus backlight blinking.

The only manufacturers of any technology TV who gives any accurate data on the reponse time is some of the newer Sharp and Philips TVs. they are using the 120Hz and blinking and usually talk of about 4ms. reponse times. Samsung is bring out some 120Hz LCD TV's without blinking that are at 8ms, essentailly identical to Plasmas. Unless you can figure out what technology they are using though the numbers published mean nothing as often the LCD change time (not the actual smaering) is published instead.

Contrast Ratio --
Again, most specs mean nothing. The static (one small area of the screen, the rest of the screen dark) is very high (>10,000)in CRT's in a black room. For PDP's it is close to 10,000. For the Better LCD's it is >1000. Unfortunatoely , you actually look at the whole screen. Then the contrast ratio for CRT's and PDPs goes down to about 400-700 as they cannot drive their whole screens to the brightest levels. LCD's are not affected by this so they are still >1000.
Newer LCD's also adjust the backlights (dim the whole backlight in dark scenes, bright in bright scenes) to give a dynamic contrast raio of >5000. The newest LCD's are using local dimming (This requires an LED based backlight) to dim individual areas of the screen. these are by far the highest performance TV's available with contrast ratios much graeter than 10,000. Unfortunately, tjhe are expensive. Samung iis the only manufacturer with themout now and the 46" goes for $4000.

In a lit room, (one 60W bulb) the contrast raios will be degarded by the TV screen reflections of the room light.CRT's and PDPs typically goe down to less than 100 contrast ratios while LCD's are better, more like 400-500.

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Regarding interlaced or progressive HDTVs
by DaveTinNY / July 13, 2007 10:35 PM PDT

Hi Nat. In the simplest terms, buy the highest resolution you can afford. 1080p format is NOT yet being broadcast by television programming. It's in 1080i. I've had a 38" 1080i TUBE TV for about five years now and the picture is phenomenal when watching HDNET and Discovery HD Theater (true 1080i HD programming) or even sports on ESPNHD or the national networks when they broadcast HD programming. The picture is as good or better than the LCD and Plasmas out there. I keep checking but have yet to see a difference in HD quality. 1080p is good if you have one of the new 1080p HD DVD PLAYERS (or BluRay) that can send their 1080p signal to the TV. That said, the 1080i HD DVDs look absolutely amazing on a 1080i HD TV too. The XBOX360 HDDVD player is a good example of this. Excellent quality and a low price. Interlaced is not a bad or cheap thing when dealing with high definition.

Whether LCD or Plasma, I'd not buy anything less than "1080"... Some "high def" TVs are only capable of "720p" - these would be ruled out by me. Not enough sharpness/resolution. Look at and compare the TV pictures. My advice: try and find a REAL home theater store, one that specializes in higher end video and audio systems; they'll have excellent listening rooms where you can sit down and experience the whole package. Look in the Yellow Pages for one of these specialized places. The people there will know what they're talking about and are usually very helpful (and courteous). The Best Buys and Circuit Citys of the world are generally filled with less sales quality than you deserve. FRY's Electronics is a decent source for everything electronics but not everywhere in the country. They SHOULD be.

i= Interlaced p= Progressive... both are excellent when the signal being sent to the HDTV is of a high quality.

Good luck whatever you choose. LOOK at the quality of the pictures and avoid the rear projection TVs. They usually lack good viewing from the side. Also buy an "HDTV" not "HD Ready" or "HD Capable." For the latter two you'll need to buy extra equipment just to see an HD picture.

Good luck!

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HDTV
by Ken Jr. / July 20, 2007 2:35 PM PDT

Don't try to figure it all out. It's a waste of time. Don't spend your money based on the specs and acronyms. Visit the TV sellers. Find a few TVs that fit within your budget and that look good to you. You'll probably even find that the picture on some 720Ps look better to you than on some other 1080Ps (If it's a 42" you probably won't even be able to tell the difference between 720P, 1080i, or 1080P). Then start reading every review you can find on those TVs. Pay special attention to the opinions on how the picture looks to the reviewers eyes under various conditions and pay attention to the comments about how easy (or hard) it is to set up (real important). Then, before you buy, find out what the return policy is, (some places allow you to bring it back if you simply don't like it, but others may charge a restocking fee). Sometimes the picture when seen in your home can look very different than what you expected or than the way it looked on the showroom floor. Lastly, if you're not good with adjustments, invite a friend over who is real good at setting up the perfect picture.

P.S. Use Google or your preferred search engine to find reviews. Just type in the TVs name, it's model number, and the word, "reviews". Typically you'll several.

P.P.S. Remember that audio on some TVs is much better than on others. You've got to play that card too.

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HDTV Tutorial
by pradike / July 13, 2007 10:47 PM PDT
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your prayers are answered
by imchin / July 13, 2007 10:50 PM PDT

that is what it means it means interlaced so you are correct and you are very smart for that congrats because i would have just gone to ask.com andtyped in the question but whatever floats your boat

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help my creative sound card...
by rattanak55 / July 13, 2007 11:30 PM PDT

um... hi

i have an creative sound card. the divice number is : CT 4810 . any one can give me its driver??

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help my creative sound card...............
by Saladdin-21227557112484760389913299193329 / July 13, 2007 11:44 PM PDT

Hello rattanaK55

It is always a good idea to go to the website (if one exists) of the creator of your product in question. Go to the website of 'Creative Labs' where you should maybe find a link to your sound card if it is not too old.

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sound card
by dan.warthan / July 20, 2007 2:22 PM PDT
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Completely unrelated question...
by petejohnson / July 20, 2007 6:01 PM PDT

I would recommend perhaps looking for a discussion on sound cards, perhaps a pc peripheral forum or a discussion about sound card drivers. I'm gonna have to say that asking about a sound card in a HDTV discussion isn't probably the best plan of attack.

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HDTV
by Jim McDiarmid / July 14, 2007 12:04 AM PDT

Buy the latest technology. Don't go for a sale price on an older set.

Costco and Sam's have great pricing on Vizio. I have had a 32" for almost a year and 4 weeks ago bought the 47" LCD 1080p for under $1600. It is awesome.

Also remember there is no reflection in the LCD screen like there is in a Plasma. We watch the LCD with all the blinds and drapes open and the screen faces the windows.

I have no connection with Vizio or any retailer, just did my own research.

Jim
Buena Park, CA

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hi
by rattanak55 / July 14, 2007 2:22 PM PDT
In reply to: HDTV

i'm ask for the " creativer soun card driver " and the number of device is ct 4810...

i do'nt ask for any LCD or CRT or any kind of this divice... so please reply me only this " sound card " ...

Best Regard...

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