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I have a new HDTV (HLM617) and an HD cable box from my cable company (TIme-Warner). There are only a couble of HD channels (CBS, ABC, HBO) I was hoping someone here could help me with some simple questions.


1) If I am watching an HD channel and it is not widescreen, does that mean the original material was not recorded as HD? It still looks great.


2) The cable box has both component outputs and regular RCA-type analog outputs. If I use the component output, the non-HD channels look really crappy (fuzzy). If I use the regular RCA outputs, the non-HD cable channels look pretty good. Is there some adjustment to the TV that help the component outputs look better? Since there is only one set of audio outputs from the cable box, I can't use both (unless I hook it to a AV receiver)


3) Is there any difference between "component" cables and regular RCA cables with three conductors (left, right, video)? The look the same to me, except for the colot coding on the end.


Thanks for your help!


Alex
 

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1. Most HD programming is in widescreen. Do you see some programs in widescreen and others not? If so, the answer could be that some of the programming is regular 4:3 upconverted to HD. If all of your HD programming is 4:3 then you may need to check the settings in your box to make sure that it is set to widescreen and to a HD resolution, also check your TV for same.


2 and 3. Your component outputs should definately look as good or better than the composite ones (regular RCA). I have a feeling that your cable box may not be setup correctly. Check your cabling. You should be using component video cables. This doesn't mean that you should go out and spend 100's on expensive cables (up to you if you want to). But they should at least be designed to be component video cables.


From your post it is possible that you are actually watching everything in 480i.


If you are still having problems post your specific hardware (TV and set top box) and I'm sure you'll get better tips than mine.


Happy viewing.
 

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Hi Alex,


Like you I have Time-Warner cable (and probably the same Scientific Atlanta box as well). To try and answer your questions:


1) Also wondered about that one. It really looks like HD material in 4:3 format. Resolution/detail is awsome. Survivor Amazon is one of those programs in this format. Gorgeous scenery (and I'm not just talking about the women). It looks too good to come from a regular SD source. Maybe the format the broadcast company receives it in is of better definition (even if it's not quite HD)?


2) Same here, though the difference is not that big. My guess is that for the component output the cable box is doing the scaling to 720p, while for the composite output the TV is doing the scaling and the TV probably has a much better scaler than the cable box. B.t.w. I've simply added a splitter to the cable signal (it's plenty large anyway) and feed one output into the cable box, the other goes into the TV. Then use the TV's tuner to view the regular analog channels.


3) There's a huge difference between component and composite (that's the left-right-video output). Component has a much higher bandwidth. Composite would not be able to carry HD material, the bandwidth just isn't there. Or to put it differently, HD would look very fuzzy if displayed through composite. In addition to the lower bandwidth, all the color and luminance information is crammed into that lower bandwidth as well. Component has it split into (a variation of) the primary color signals. The result is that component is capable of transporting much better looking pictures than composite. That's why you really want to use component over composite for sources like DVD as well.


-Rob-
 

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Quote:
Originally posted by Slartibartfast1

1) If I am watching an HD channel and it is not widescreen, does that mean the original material was not recorded as HD? It still looks great.


2) The cable box has both component outputs and regular RCA-type analog outputs. If I use the component output, the non-HD channels look really crappy (fuzzy). If I use the regular RCA outputs, the non-HD cable channels look pretty good. Is there some adjustment to the TV that help the component outputs look better? Since there is only one set of audio outputs from the cable box, I can't use both (unless I hook it to a AV receiver)


3) Is there any difference between "component" cables and regular RCA cables with three conductors (left, right, video)? The look the same to me, except for the colot coding on the end.
1. Often 4:3 programs on HD channels are upconverted, meaning they began as ~720X480 SDTV and were electronically processed into 1280X720p or 1920X1080i. (Some SDTV tapes have greater, 1000-line plus, horizontal resolution.) Upconversions lack the resolution of programming originally captured with a HD camera or telecined from film in HDTV. Rare presentations, such as Showtime's "Greatest Show on Earth" last year, appear to have preserved this vintage film's 4:3 format but delivered it in true 1080i with bars on either side.


2. The component outputs should be used for H/DTV sources only, meaning HDTV sources such as HBO or DTV sources such as local digital-TV stations. Non-H/DTV channels (SDTV) look fuzzy because some converters, such as the SA3100HD often used by TWC, upconvert all SDTV to 1080i. Modest mass-produced upconverter circuits for cable converters don't perform that well. I find S-video works best for higher-numbered digital-cable channels, roughly >100. But often below 100 there's dot crawl and image graininess on my system. So for extended viewing, when these artifacts are present, I switch to composite (video) out. This is a heavily filtered NTSC signal, with lower resolution than S-video, that employs the comb filter in most sets, minimizing the artifacts. 3100HD users often make use of the digital-audio-out jack with a Dolby-surround-type receiver. I and others have found that a Y-type audio connector splits the L/R audio out to feed two stereo-in connections if necessary.


3. Component video cables should be 75 ohms, while other cables with RCA-type connections may not have this impedance.
 

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quick about the cables..


the yellow (composite of a/v cable) is most likely sufficient for one color of the component video, however the red and white audio cables are _usually_ much lower spec and will most likely give very poor results if used as video cables.
 

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If you want to really fill your screen with the 4:3 broadcast and get rid of the vertical black bars, you can do this: manuall change the setup of your HD box from widescreen to 4:3. The image will then fill up the screen !


However, your 16:9 HD broadcast will look smaller.


Leo
 

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You asked:


2) The cable box has both component outputs and regular RCA-type analog outputs. If I use the component output, the non-HD channels look really crappy (fuzzy). If I use the regular RCA outputs, the non-HD cable channels look pretty good. Is there some adjustment to the TV that help the component outputs look better? Since there is only one set of audio outputs from the cable box, I can't use both (unless I hook it to a AV receiver)


I say:

The HD component in is designed to intake very high quality material and display it without too much manipulations. It assumes very good quality content. Unfortunately regular cable tv channels are not very good quality. Garbage in/Garbage out principle. They could use the help of any of the TV's special filters to clean it up before displaying it.

Mostly these special manipulations and filters are done to composite and coax inputs and not so much to s-video and component, especially HD component in. Try some different inputs and see if you cannot get something better looking from the non-HD channels.


My Toshiba 42HDX82 makes regular cable look best using coax in or composite in due to it's Cableclear manipulations feature and 10 Mb 3D y/c digital comb filter.

On my Tv you can adjust on different connectors but not store two or three different sets of settings for one connector so you will likely need to split the cable and get creative with connections to get the best picture on non-hd and as well as hd.


Maybe consider run a coax through the vcr and watch non-hd cable through there using s-video or composite to the Tv.


Is there a s-video out on the cable box in addition to hd component out . Maybe you can use that on another video in and get better results.


Also make sure all your coax is RG-6.


Good Luck

Dee
 

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I have a 507W and just (today) got the Comcast HD box (motorola 5100). Analog channels look like real **** through component. So I just ran a standard coax cable from 5100 to ANT input.


Now I can watch analog channels with ANT input and HD channels with Component input. I would have liked to use the composite output of 5100 versus coax, but there is only one audio out and that is tied to my component.


I have a question: if I watch a HD program through my coax, will I get my 16:9 wide screen (meaning it will look good and NOT expand like it does with standard 4:3 programming)? Maybe not as clear as component, but would love to get wide. Just like CSI, etc programs. I will have to play, but any insite would be nice.


One other nasty item is that info normally displayed by 5100 when tv using component mode (station, etc.) does not show up under ANT input. Do others have this problem?


Thanks,


Chuck
 

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Chuck, you might try the Y-connection I mentioned earlier for two stereo outs. Fidelity-wise, S-video is better than composite, which may be slightly better than RF out. Component out, assuming a component source, is best of all.

My SA3100HD cable converter, and most STBs, won't downconvert HD sources to produce SDTV outputs (for 'stretching'). Some newer STBs and one older DBS STB do downconvert HD. -- John
 
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