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  1. Member
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    I am looking to buy my first LCD TV. I am very confused as to what will give me the best picture quality considering I have SD digital cable. I'm sure I'll upgrade to HD at some point in time, I just don't know when.

    I plan on buying a 32" TV and I'm just not sure what I should be looking for. Would 720p or 1080p be better for SD digital cable? And what about the refresh rate? I know there are other factors that play into picture quality, I just don't know what they are. At the same time, I want to buy a TV that will also have good picture quality when viewing HD channels. The people that will watch this TV are all used to perfect, crystal clear picture quality on a CRT TV displaying SD channels.

    Any suggestions as to what I should be looking for in my new TV in order to get the best picture quality?
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  2. Other things being equal, SD digital will look about the same on both 720p and 1080p HDTVs. More important is the quality of the deinterlacer and the up-scaler, the black level, etc. Unfortunately, such things aren't quoted in the specs. You have to see the TVs for yourself.

    Even with HD material you may not notice much difference between 720p and 1080p displays, depending on the size of the TV and how far away you sit from it. With a 32" display you won't see any difference between 720p and 1080p beyond about 6 feet. Beyond 9 feet you won't see the difference between SD and HD. The chart on this page will give you an idea:

    http://carltonbale.com/1080p-does-matter

    But the price premium for 1080p isn't large any more. I'd just go ahead and get it. With 1080p material you could watch a 32" HDTV from less than 3 feet away and still have a nice sharp picture free of the screen door effect (visible pixels). You can even use it as a computer monitor and have a perfectly sharp and readable desktop. And a 1080p models are likely to have better quality electronics than 720 models.

    Regarding refresh rates: the 120 and 240 Hz displays can remove the judder from film based material (removing only the judder still leaves you with the inherent jerkiness of 24 fps film). They can also smooth out the motion of film based material by creating in-between frames with interpolated motion. That works well with some material, not so well with other material. When it works, some people like the smoother motion, some don't. They also claim to have less motion blur, and you can see it with special test patterns, but it doesn't seem to make much difference in real world video.

    The following page has a shootout between plasma and LCD. Within it they discuss the motion blur issue:
    http://www.extremetech.com/article2/0,2845,2349236,00.asp
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  3. Member
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    After I typed in a long and thoughtful post Videohelp timed me out and dumped everything. So I'll be more brief here.

    1) Don't stretch everything to 16:9. Watch 4:3 in 4:3. If you must fill the screen then use the intelligent zoom function to do it.
    2) Use only high quality connections like HDMI, DVI and Component (NOT composite!) to your TV from your video sources.

    Some HDTVs sold in the USA don't support PAL at all. You may not care about that. Most don't but a few do. Avoid Samsung if you care as their HDTVs do NOT support PAL at all, but otherwise they make a fine product that me and others I know have been pleased with.
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  4. Member edDV's Avatar
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    Originally Posted by lilblu View Post
    The people that will watch this TV are all used to perfect, crystal clear picture quality on a CRT TV displaying SD channels.
    I highly recommend you get the HD cable tuner. It doesn't add much much monthly cost at least with Comcast. Here Comcast provides over 80 HD channels plus many more HD programs on VOD.

    SD "digital" is only 528x480i. For display on an HD set, 480i must be deinterlaced to 480p, then upscaled to 1366x768 (aka 720p but isn't) or 1920x1080p. The quality of this deinterlace and upscale usually tracks the cost level of the HDTV. The cheaper models will be the worst for watching SD.

    Most North American HDTV sets these days have both ATSC (over air) and QAM (cable) tuners. The QAM tuner will get the locals plus unencrypted cable sub channels in SD or HD regardless of whether you subscribe to HD service.
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  5. Member yoda313's Avatar
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    Originally Posted by jagabo
    Beyond 9 feet you won't see the difference between SD and HD. The chart on this page will give you an idea:
    I can't talk about the distance factor as I don't have that big of a room where I watch my 32" hdtv.

    But the one area that hd and sd are noticeable is sports. If you watch sports HD is a must. It is just so much better in hd.

    The one difference is more channels are starting to broadcast in letterbox widescreen so you can preserve the widescreen and use your tv to zoom without distorting the picture. - when watching a sd channel on a hd set that is.

    I do agree with eddv that the hd package is worth it. The picture is generally much crisper. Also most are 1.85:1 widescreen so the channels "fill the screen" if that matters to you. With sd you'll have to manually zoom your set to get rid of the vertical pillar bars and "fill the screen" without distorting the picture.

    Also you'll never go back once you get an dvr. Plus 5.1 is fun though I don't use it much on my cable but its nice to have it.
    Last edited by yoda313; 29th Apr 2011 at 14:34.
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  6. Originally Posted by lilblu View Post
    Any suggestions as to what I should be looking for in my new TV in order to get the best picture quality?
    Unless you're planning on sitting about 4 feet away, get a bigger TV.
    Originally Posted by lilblu View Post
    I'm sure I'll upgrade to HD at some point in time, I just don't know when.
    I also just have Standard-Def cable, but I receive all the networks and a few others in Hi-Def. The cable companies are required to provide the network stations in Hi-Def at no additional charge if you have even the cheapest cable package.
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  7. Originally Posted by manono View Post
    Originally Posted by lilblu View Post
    Any suggestions as to what I should be looking for in my new TV in order to get the best picture quality?
    Unless you're planning on sitting about 4 feet away, get a bigger TV.
    It's common for people to regret having bought too small a TV. And it's very rare that people regret having bought too large a TV.
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  8. Member edDV's Avatar
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    Agreed. Even a bedroom needs at least 42".

    A 32" 16:9 TV has about the same 4:3 image size as a 26" CRT. Try this calculator.

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    http://tvcalculator.com/

    26" 4:3 vs 42" 16:9

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    Last edited by edDV; 29th Apr 2011 at 22:29.
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  9. Member
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    I appreciate the help. I have a few concerns though.

    If I did get HD cable, it probably wouldn't be for at least 6 months. I need to get the coaxial cable replaced in the house due to a low signal and am having issues with that. So I'm gonna have SD for at least 6 more months. The cable box I have now only has two types of outputs: coaxial and composite. So I'm gonna have to connect the TV to the cable box via composite cables, I guess.

    Another thing is the price of TVs. I didn't realize how much they cost. They're a lot more than CRTs. I was hoping the prices would've come down by now. I can't justify spending $400 for a new TV. I spent $266 on my last 27" CRT. If I bought a LCD that has the same viewing area, then I would need to buy a 32" which costs at least $310 for a cheap brand name. A fairly decent TV probably costs at least $400 and a high quality TV could cost up to $1000, maybe more. That's crazy. I don't know what to do. Especially because I want a TV with 120Hz refresh rate as I think 60Hz might look bad. I can't find anything within my budget.
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  10. Originally Posted by lilblu View Post
    So I'm gonna have to connect the TV to the cable box via composite cables, I guess.
    Then there's no point at all in getting a Hi-Def TV set. Stick with what you have until the problems are resolved. And save your money. You a member of Costco?

    http://www.costco.com/Browse/Product.aspx?Prodid=11536849&whse=BC&Ne=5000135+40 00000&eCat=BC|90607|2341&N=4047300%204294899203&Mo =17&No=6&Nr=P_CatalogName:BC&Ns=P_Price|1||P_SignD esc1&lang=en-US&Sp=C&topnav=

    The point is that these sets are cheaper than you might think. And Vizio is a decent lower-priced brand. You don't have to start with a Sony. And they get cheaper all the time.
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  11. Member edDV's Avatar
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    Originally Posted by lilblu View Post
    I appreciate the help. I have a few concerns though.

    If I did get HD cable, it probably wouldn't be for at least 6 months. I need to get the coaxial cable replaced in the house due to a low signal and am having issues with that. So I'm gonna have SD for at least 6 more months. The cable box I have now only has two types of outputs: coaxial and composite. So I'm gonna have to connect the TV to the cable box via composite cables, I guess.

    Another thing is the price of TVs. I didn't realize how much they cost. They're a lot more than CRTs. I was hoping the prices would've come down by now. I can't justify spending $400 for a new TV. I spent $266 on my last 27" CRT. If I bought a LCD that has the same viewing area, then I would need to buy a 32" which costs at least $310 for a cheap brand name. A fairly decent TV probably costs at least $400 and a high quality TV could cost up to $1000, maybe more. That's crazy. I don't know what to do. Especially because I want a TV with 120Hz refresh rate as I think 60Hz might look bad. I can't find anything within my budget.
    The cable signal level is set by the cable company up on the pole in their amp. More important for HD is they equalize the frequency response since many of the HD subchannels are in the upper RF channels. Get the HD cable box and try it. If you don't get all the channels, connect the box where the cable enters the house. If it doesn't work there, they owe you a visit without charge to set equalization and levels.

    How far do you plan to sit from this TV?
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  12. Originally Posted by lilblu View Post
    I want a TV with 120Hz refresh rate as I think 60Hz might look bad.
    Do you realize you've been watching 60 Hz TV your entire life?
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  13. Member
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    Originally Posted by jagabo View Post
    Originally Posted by lilblu View Post
    I want a TV with 120Hz refresh rate as I think 60Hz might look bad.
    Do you realize you've been watching 60 Hz TV your entire life?
    Indeed. I bought my Samsung LCD HDTV about 4 years ago and it's a 60 Hz model and I've loved it. At the time I bought it there were no 120 Hz options available, at least not in that price range. Few consumers really and truly care about higher refresh rates. Some of the ones who do care are very vocal about it. And some of them are vocal about not liking it at all. But honestly most random consumers can't tell the difference. My constant advice to friends has been that the odds are quite high that they won't be able to tell the difference and as such they shouldn't pay more money for higher refresh rates unless they are absolutely sure that they are one of the people who can tell the difference. Really most people are just not that fussy about their HDTVs. They stretch everything to 16:9 anyway.
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  14. Member
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    Originally Posted by jman98 View Post
    Originally Posted by jagabo View Post
    Originally Posted by lilblu View Post
    I want a TV with 120Hz refresh rate as I think 60Hz might look bad.
    Do you realize you've been watching 60 Hz TV your entire life?
    Indeed. I bought my Samsung LCD HDTV about 4 years ago and it's a 60 Hz model and I've loved it. At the time I bought it there were no 120 Hz options available, at least not in that price range. Few consumers really and truly care about higher refresh rates.
    But a 60Hz CRT and a 60Hz LCD TV are quite different. CRTs need high refresh rates to avoid refresh flicker becoming visible. As I understand it, LCDs don't exhibit this issue as the backlight typically runs at much higher refresh rates anyway. The '60Hz' figure refers to the rate the LCD pixels are updated:
    http://en.wikipedia.org/wiki/Refresh_rate#Liquid_crystal_displays

    'refresh flicker' is a separate issue to flicker/judder caused by content with low frame rates - for example when watching films shot at 24fps.

    I can't see any sign of flicker on my LCD computer display which runs at 60Hz. The CRT next to it is running at 75Hz, and there's still noticeable flicker with that.
    Last edited by intracube; 30th Apr 2011 at 09:11.
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  15. Member edDV's Avatar
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    Originally Posted by intracube View Post
    I can't see any sign of flicker on my LCD computer display which runs at 60Hz. The CRT next to it is running at 75Hz, and there's still noticeable flicker with that.
    Classic CRT TV sets are all refreshed at 59.94 fields per second (50 fields per second for PAL/SECAM). 59.94 Hz is adequate refresh for an interlace TV due to the decay rate of the phosphors used and because the eye tends to average the fields. 50Hz can appear more flickery but the brain seems to adapt over time.

    CRT computer monitors are a different story. First they use the desktop model where the background is flat white. This makes 60Hz flicker more obvious. Second a computer monitor uses progressive scan so doesn't get the phosphor averaging effect of interlace. Computer CRT monitors need a >60Hz refresh rate to minimize flicker. For most people, >75 Hz is needed to make the background flicker free.

    As explained above, LCD monitors have a continuous full on white backlight that is modulated by LCD refresh. Flicker isn't the issue so much as fast motion update. Early LCD screens couldn't fully update from black to white at a 60Hz rate so fast motion showed trails of previous frames. This has been improved in current models making LCD acceptable as a TV. Today's LCD screens can update motion at 60/120/240 fps rates.

    The main reason 120/240 fps update is used for NTSC/ATSC is to properly display 24 fps film source. 24 (23.976) does not evenly divide into 60 (59.94) so film source must be displayed as 2x then 3x frame repeats to build up to 60 (59.94). The fast-slow-fast-slow display rate on "60Hz" TV sets is called judder.

    When 24 (23.976) fps film is frame repeated 5x-5x-5x-5x it matches the 2x 60 (59.94) ATSC rate for broadcast 1080i or 720p. And since the update rate is continuous, there is no judder.

    24 x 5 = 120 (23.976 x 5 = 119.88)
    60 x 2 = 120 (59.94 x 2 = 119.88)
    30 x 4 = 120 (29.97 x 4 = 119.88)

    So 120 fps (119.88 actual) is an ideal rate to display all ATSC/film. Film is displayed without judder just like in a cinema. Nobody complains about 5x frame repeats to "120 Hz".

    A separate issue is frame repeat vs intermediate frame interpolation. When frame interpolation is used 4 of the 5 frames are calculated as an intermediate estimate rather than simply repeated. The idea is smooth out the motion. There are artifacts when using this method. Some people like it some don't. In all 120/240 Hz HDTV sets, you can turn off frame interpolation if you don't like it.
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  16. Member yoda313's Avatar
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    Originally Posted by eddv
    The main reason 120/240 fps update is used for NTSC/ATSC is to properly display 24 fps film source. 24 (23.976) does not evenly divide into 60 (59.94) so film source must be displayed as 2x then 3x frame repeats to build up to 60 (59.94). The fast-slow-fast-slow display rate on "60Hz" TV sets is called judder.
    In INDEPENDENCE DAY the dvd commentary stated that the helicopter blades in the "welcome wagon" scene look funny because of converting to 30fps for the dvd. Is that related to this film conversion issue? (the scene I'm referring to is when the miliatry is using the lights on the helicopters trying to "communicate" with the mothership over dc - I think its the dc one).

    Does the bluray of independce day still exhibit this issue? Is the bluray a true 24fps? I don't have the bluray just the dvd. Was wondering if the newer print would clear it up and if you need a 120hz or greater set to properly display it.
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  17. Member
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    Originally Posted by edDV View Post
    Classic CRT TV sets are all refreshed at 59.94 fields per second (50 fields per second for PAL/SECAM). 59.94 Hz is adequate refresh for an interlace TV due to the decay rate of the phosphors used and because the eye tends to average the fields. 50Hz can appear more flickery but the brain seems to adapt over time.
    As I live in PAL land, I haven't had much exposure to NTSC video for most of my life. But the last few years I've been importing R1 DVDs and watching US satellite feeds, and it's surprising how watching just an hour or so of NTSC content can subsequently make the PAL flicker stand out.

    Some time ago I had a theory that staring at a flickering screen (where one field was light grey, and the other dark grey) would have a desensitising effect*. So I created a test DVD, sat myself in front of the screen for a few minutes, then switched back to a regular PAL broadcast. The result; silky smoooooth and virtually no perceptible flicker (for about 10 minutes, anyway).
    *not recommended for anyone with photosensitive epilepsy...

    CRT computer monitors are a different story. First they use the desktop model where the background is flat white.
    Also, people look at TVs from a greater distance compared to computer screens. A smaller image can hide the refresh limitations.

    As you say, large areas of white make the flicker obvious, which is why TV graphics usually stick to darker colours. Some broadcasters in the UK (BBC News, C4 News) have been ignoring that 'rule' in recent years - which is sort of sticking two fingers up to people watching on CRTs:

    How it was:
    http://www.youtube.com/watch?v=h8kGSBN7cus#t=29
    http://www.youtube.com/watch?v=kvCjQ7SJeQs#t=16

    How it is now:
    http://www.youtube.com/watch?v=_fxf0ePqMWM#t=51s
    http://www.youtube.com/watch?v=dXyaAY5Mujo#t=35s

    When 24 (23.976) fps film is frame repeated 5x-5x-5x-5x it matches the 2x 60 (59.94) ATSC rate for broadcast 1080i or 720p. And since the update rate is continuous, there is no judder.
    ..
    So 120 fps (119.88 actual) is an ideal rate to display all ATSC/film. Film is displayed without judder just like in a cinema. Nobody complains about 5x frame repeats to "120 Hz".
    True, the 'film to NTSC' telecine judder is avoided - but there's still the inherent limitation of film's 24fps (except for TVs that have a frame motion interpolation feature).

    Originally Posted by yoda313 View Post
    In INDEPENDENCE DAY the dvd commentary stated that the helicopter blades in the "welcome wagon" scene look funny because of converting to 30fps for the dvd. Is that related to this film conversion issue? (the scene I'm referring to is when the miliatry is using the lights on the helicopters trying to "communicate" with the mothership over dc - I think its the dc one).
    I've got the R1 4:3 DVD of Independence Day and looking at that scene I can't see anything that stands out. Can you describe what looks odd?

    The 2:3 pulldown process gives a distinctive stutter/judder effect. Separate to that issue, when filming rotating objects (helicopter blades, car wheels, etc) there's sometimes an optical effect (caused by the limited frame rate and the exact alignment of a rotating object over multiple frames) that can give the illusion that an object is rotating incredibly slowly, or even backwards.

    Having said that, there are some oddities with the ID DVD. Most of the DVD is 24000/1001 (23.976)fps with the 2:3 pulldown being done by the DVD player. However, sporadically throughout the disc, the framerate jumps to 29.97fps. AIUI, this isn't in itself uncommon. All it usually means is the content is jumping from 'soft telecine' to 'hard telecine'. The ID DVD looks different...

    From the bits of the film that I've looked at, the 29.97fps sections are VFX shots which seem to be 30p. Yes, I do mean 30p! Actually, it's 59.94i as each film frame is straddled across two fields. For example, instead of:
    1a 1b , 2a 2b , 3a 3b , 4a 4b , 5a 5b
    it's:
    1a 2b , 2a 3b , 3a 4b , 4a 5b , 5a 6b

    Watching it on a TV to eliminate any PC playback issues, the 59.94i sections look absent of the usual telecine judder, and the motion looks smoother and more like regular video. I have no idea why the DVD has these '30p' sections.
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  18. Member lacywest's Avatar
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    If your going to watch SD on a HDTV ... consider what HDTV you get ... some do a better job of resizing the picture your looking at.

    Sony ... avoid ... the HDTV in the living room is a Sony ... and it is a biatch to get the letter box or other shows to look right. It was bought in 2005. Since then ... I've bought a Sony 31" LCD HDTV ... same similar problems getting the picture to adjust right for different formats.

    But the Panasonic in the bedroom ... is a 42" Plasma ... the resize button on the remote ... excellent ... a letter box show on the SY FI channel ... [ I dont get it in HD ] ... fills the screen just right.
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  19. Originally Posted by lacywest View Post
    Sony ... avoid ... the HDTV in the living room is a Sony ... and it is a biatch to get the letter box or other shows to look right...

    But the Panasonic in the bedroom ... is a 42" Plasma ... the resize button on the remote ... excellent ... a letter box show on the SY FI channel ... [ I dont get it in HD ] ... fills the screen just right.
    Is that your problem with the Sony TVs? I prefer not to zoom letterboxed SD material because it gets too blurry. That will vary for others depending on the size of the TV and viewing distance though.
    Last edited by jagabo; 3rd May 2011 at 08:17.
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  20. I have a Sony and don't have to do anything - everything plays in perfect aspect ratio. And I don't zoom widescreen SD shows either.
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  21. Member yoda313's Avatar
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    Originally Posted by intracube
    I've got the R1 4:3 DVD of Independence Day and looking at that scene I can't see anything that stands out. Can you describe what looks odd?

    The 2:3 pulldown process gives a distinctive stutter/judder effect. Separate to that issue, when filming rotating objects (helicopter blades, car wheels, etc) there's sometimes an optical effect (caused by the limited frame rate and the exact alignment of a rotating object over multiple frames) that can give the illusion that an object is rotating incredibly slowly, or even backwards.
    Yes I realized I should have been more descriptive after my post.

    That was what was being discussed on the commentary track. The the helicopter blades looked odd on the dvd.

    Thanks for the information.

    (edit that the speed of the blades looks odd)
    Last edited by yoda313; 3rd May 2011 at 12:39.
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  22. Member
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    Originally Posted by yoda313 View Post
    That was what was being discussed on the commentary track. The the helicopter blades looked odd on the dvd.
    ..
    (edit that the speed of the blades looks odd)
    Here's an extreme example:
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  23. Member yoda313's Avatar
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    Holy crap!

    Thanks for the link intracube.

    That looks like its cg or some kind of model
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  24. It's often called the wagon wheel effect because it would show up in old Westerns a lot. Here's a good example:

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  25. Member
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    lilblu; One thing that hasn't been mentioned on this thread is overscan. I haven't got an LCD TV, but I've heard it can be an issue as not all TVs have an option to disable it. I don't know how widespread the problem is now; some of the comments I've seen are several years old and the situation may have changed. Hopefully someone else can give advice here.

    If a TV has overscan, the outer edge of the image will be cropped to some degree. It also means the screen might have to do additional scaling/interpolation of the image which can lower the picture quality.

    For example, even if you have a source that's 1920x1080 and a screen that's also natively 1920x1080, the TV may take the 1920x1080 input, crop 5% from each side (leaving an 1728x972 image), then scale that image back up to 1920x1080.

    Any decent screen should be able to do 1:1 pixel mapping to maintain quality (assuming the resolution of the source and the flat panel match).

    Here's an old thread (circa 2007) discussing the issue:
    http://www.avsforum.com/avs-vb/archive/index.php/t-826448.html
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  26. Member yoda313's Avatar
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    Originally Posted by jagabo
    It's often called the wagon wheel effect because it would show up in old Westerns a lot. Here's a good example:
    Is that the reason why car wheel hubcaps sometimes look like they are going the opposite direction than they should be in some videos?
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  27. Member
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    Originally Posted by jagabo View Post
    It's often called the wagon wheel effect because it would show up in old Westerns a lot. Here's a good example:
    Ah, that's the sort of clip I was searching YT for! Great example. I wasn't sure of the name of the optical effect, so I didn't have much luck finding good examples.
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  28. Originally Posted by yoda313 View Post
    Is that the reason why car wheel hubcaps sometimes look like they are going the opposite direction than they should be in some videos?
    Yes. It's a form of temporal aliasing.
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  29. Member edDV's Avatar
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    Originally Posted by intracube View Post
    lilblu; One thing that hasn't been mentioned on this thread is overscan. I haven't got an LCD TV, but I've heard it can be an issue as not all TVs have an option to disable it. I don't know how widespread the problem is now; some of the comments I've seen are several years old and the situation may have changed. Hopefully someone else can give advice here.

    If a TV has overscan, the outer edge of the image will be cropped to some degree. It also means the screen might have to do additional scaling/interpolation of the image which can lower the picture quality.

    For example, even if you have a source that's 1920x1080 and a screen that's also natively 1920x1080, the TV may take the 1920x1080 input, crop 5% from each side (leaving an 1728x972 image), then scale that image back up to 1920x1080.

    Any decent screen should be able to do 1:1 pixel mapping to maintain quality (assuming the resolution of the source and the flat panel match).

    Here's an old thread (circa 2007) discussing the issue:
    http://www.avsforum.com/avs-vb/archive/index.php/t-826448.html
    Fortunately, most HDTV sets now have the pixel for pixel (aka "just scan") mode. It is a must for displaying computer desktops and usually gives the sharpest picture. Downside is this mode often shows vertical interval closed caption data at the top for SD source.

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    Last edited by edDV; 3rd May 2011 at 14:26.
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  30. Member yoda313's Avatar
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    Originally Posted by jagabo View Post
    Originally Posted by yoda313 View Post
    Is that the reason why car wheel hubcaps sometimes look like they are going the opposite direction than they should be in some videos?
    Yes. It's a form of temporal aliasing.
    Thanks.
    Donatello - The Shredder? Michelangelo - Maybe all that hardware is for making coleslaw?
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