The "Myth" oh HD on 100 Hz

[Tackler]

First post here guys...be gentle!

I've just read this on an ebay seller's website and was hoping someone could clarify, agree or dismiss the following statement....

"We also want to touch on the myth of High Definition on 100hz TV's. Just because you buy a 100hz TV does not not mean it's HD! It doesn't matter what the adds says, even if it does say it will do HD! You have to understand that CRT TV's only have around 480-576 lines. So you can't possibly get a true 720 or 1080 HD picture, it simply doesn't have the resolution to support this! It will however accept the signal! but because it doesn't have the lines/pixels to support this you are still only getting a standard digital picture. You might be wondering why we are telling you this? wouldn't this hurt sales? We think it's better to tell people the truth rather than to mislead you and say yer it will take HD, while the poor customer thinks they are watching true HD picture when in actual fact they are still only getting an up-scaled SD picture.

So in summary you might still be wondering what it all means, well this TV, and every other TV like this will take the actual HD signal, but it won't display a true HD picture"

I am thinking of buying an LG 76cm Lafinion 100hz television and was wanting to know whether there's any advantage in buying an HD STD over a SD STB. Will I be missing something if I go SD STB instead of HD? Am I wasting my money if I buy HD STB over SD? Is there any benefit of an HD STB on a 100hz?

Any help u guys can provide would be much appreciated!

[Mr_Gimlet]

  Tackler said:

I am thinking of buying an LG 76cm Lafinion 100hz television and was wanting to know whether there's any advantage in buying an HD STD over a SD STB. Will I be missing something if I go SD STB instead of HD? Am I wasting my money if I buy HD STB over SD? Is there any benefit of an HD STB on a 100hz?

Any help u guys can provide would be much appreciated!

<{POST_SNAPBACK}>

Back in my pre-plasma days (ie two weeks ago) I had a Loewe Calida which is one of the better quality CRTs available out there. When I first got into DTV, which was because of my crap analogue reception, I actually found the SD boxes were outputting what to me looked a better picture. Now things have moved in since my clunky Strong box, but I thought the HD picture was worse through my Loewe, and the extra money for HD swung it.

In technical terms, I am not your man - but my basic understanding is that all CRTs are SD, some with better pictures than others. I am open to correction.

[loser]

  Tackler said:

First post here guys...be gentle!

I've just read this on an ebay seller's website and was hoping someone could clarify, agree or dismiss the following statement....

"We also want to touch on the myth of High Definition on 100hz TV's. Just because you buy a 100hz TV does not not mean it's HD! It doesn't matter what the adds says, even if it does say it will do HD! You have to understand that CRT TV's only have around 480-576 lines. So you can't possibly get a true 720 or 1080 HD picture, it simply doesn't have the resolution to support this! It will however accept the signal! but because it doesn't have the lines/pixels to support this you are still only getting a standard digital picture. You might be wondering why we are telling you this? wouldn't this hurt sales? We think it's better to tell people the truth rather than to mislead you and say yer it will take HD, while the poor customer thinks they are watching true HD picture when in actual fact they are still only getting an up-scaled SD picture.

So in summary you might still be wondering what it all means, well this TV, and every other TV like this will take the actual HD signal, but it won't display a true HD picture"

I am thinking of buying an LG 76cm Lafinion 100hz television and was wanting to know whether there's any advantage in buying an HD STD over a SD STB. Will I be missing something if I go SD STB instead of HD? Am I wasting my money if I buy HD STB over SD? Is there any benefit of an HD STB on a 100hz?

Any help u guys can provide would be much appreciated!

<{POST_SNAPBACK}>

100 hz means nothing as far as HD goes, It is all 24,50 or 60hz. There are no SD or HD 100 hz images, 100 hz simly refeshes the same image 4 times instead of 2 times per second.

If CRT was not capable of more than 576 line my PC monitor would not be able to display 1200x1600.

A CRT's resolution depends on how quickly it can paint lines on the screan. From memory If a CRT has a refresh speed of abut 33 khz it can display a 1080i or 720p HD picture.

[kaanage]

SD CRT TVs have a shadow mask with less than 720 distinct lines while HD CRT TVs have shadow masks with at least 720 lines. Most computer CRT monitors have far more lines in their shadow masks than TVs as until HD there was no need for a TV to be able to display more than 576 lines.

Sony and others produce HD CRT TVs but that LG set is not HD so an SD stb is fine unless you plan to use it with another display (actually, its manual says it can take a 576p signal which HD stbs will generate so that may improve quality but get it demoed to be sure).

An SD TV that can handle the bandwidth can display but not fully resolve a HD signal.

Greg

[Tackler]

Thanks guys....so it looks like I don't need the HD STB is what you're telling me as the tv can't handle it? I should just buy a SD STB?

I guess buying the HD STB will "future proof" me to some degree if I'm using it on something else down the track.

CRT's that are promoted as "HD Ready"....what's that about?

[Moby58]

OK, from the DBA FAQ

Australian broadcasters are using two different levels of high definition;

– 1920 pixels x 1080 lines @ 50Hz interlaced

– 720 pixels x 576 lines @ 50Hz progressive

From my understanding of interlace from the old Amiga days, your normal picture on screen is drawn at 50hz (50 refreshes per second)

In interlace mode, every refresh is the lines between the previous lines.

That is, one cycle would draw a set of lines across the screen, the second cycle would draw between those lines, 3rd cycle would do the first lines again, etc.

So, in effect, any dot on screen was refreshed at 25 Hz. This produced a noticable flicker, as the brightness of a dot would fade before being lit again.

If you can then output, and the monitor receive, 100Hz, then you are effectively refreshing each set of lines at 50Hz, and should get no flicker.

So, yes, for interlaced HD you need 100 Hz.

  Tackler said:

First post here guys...be gentle!

I've just read this on an ebay seller's website and was hoping someone could clarify, agree or dismiss the following statement....

"We also want to touch on the myth of High Definition on 100hz TV's. Just because you buy a 100hz TV does not not mean it's HD! It doesn't matter what the adds says, even if it does say it will do HD! You have to understand that CRT TV's only have around 480-576 lines. So you can't possibly get a true 720 or 1080 HD picture, it simply doesn't have the resolution to support this! It will however accept the signal! but because it doesn't have the lines/pixels to support this you are still only getting a standard digital picture. You might be wondering why we are telling you this? wouldn't this hurt sales? We think it's better to tell people the truth rather than to mislead you and say yer it will take HD, while the poor customer thinks they are watching true HD picture when in actual fact they are still only getting an up-scaled SD picture.

So in summary you might still be wondering what it all means, well this TV, and every other TV like this will take the actual HD signal, but it won't display a true HD picture"

I am thinking of buying an LG 76cm Lafinion 100hz television and was wanting to know whether there's any advantage in buying an HD STD over a SD STB. Will I be missing something if I go SD STB instead of HD? Am I wasting my money if I buy HD STB over SD? Is there any benefit of an HD STB on a 100hz?

Any help u guys can provide would be much appreciated!

<{POST_SNAPBACK}>

[blairy]

Checked the specs of the Lafinion on th LG website. This is not an HD set as it only takes 576P. With this set you'd only need an SD box.

HD ready means it will take a signal of 1080i or 720p.

The 100Hz issue doesn't apply to HD signals. This only becomes an issue when watching analogue fta, vcr, foxtel or dvd via composite, s-video or YCbCr interlaced component inputs (as opposed to progressive scan YPbPr inputs).

Whether HD ready tv's truly display hd or not is neither here nor there. The PQ is better to my eyes than an SD tv set.

The 100Hz feature for fox and dvd etc does make a limited improvement. (NB: with my vcr 100Hz does not work )

Good luck

blairy

[firestorm]

  Tackler said:

I am thinking of buying an LG 76cm Lafinion 100hz television and was wanting to know whether there's any advantage in buying an HD STD over a SD STB. Will I be missing something if I go SD STB instead of HD? Am I wasting my money if I buy HD STB over SD? Is there any benefit of an HD STB on a 100hz?

<{POST_SNAPBACK}>

First of PAL is 625 lines vertical resolution which due to vertical blanking 50 lines are lost giving 575 lines. You then lose a few more due to over scan, which is about 5%.

You can get CRT TV’s with higher resolution than this e.g. Panasonic TX-76PW300A. It has an 833i mode giving 833 lines vertically also there are 2,376 samplings per line whereas your standard CRT TV it is 720 samples per line.

It also uses a fine pitch CRT so that means it will have a pitch of about 0.4mm by comparison a standard CRT for TV is 0.7mm, A CRT monitor pitch is about 0.23mm and a Plasma panel is 0.8mm.

In case you didn’t know DVD quality is 720 x 576.

As for your LG TV well LG don’t give much in the way of specs but they do mention it is 576p in other words it is progressive scan. A SD STB wont do 576p while all HD STB’s will do 576p. For some stupid reason 576p is considered high definition when in reality it should be considered as enhanced definition. So yes you will miss out on 576p if you don’t buy a HD STB.

  Quote

CRT's that are promoted as "HD Ready"....what's that about?

Just the same as you can get SD Plasma’s (usually resolution of 820 x 480) that have HD input. HD ready means the TV will accept a HD signal and via means of an internal scaler display the image on the screen but of coarse the image on the screen won’t necessarily be in HD.

BTW Nine’s HD channel (not in all states) has a resolution of 1920 x 1088 and at this point in time I am not aware of any TV capable of having that kind of screen resolution and even if there was a TV that could display it, it is unlikely at the viewing distance most people watch that they would be able to see it.

[DavoNogo]

I just have to say Sony KVHR36M31 - one of the highest resolving HD CRTs you'll ever see... somewhere in the vacinity of 960 to 1030 lines or so (would have to search for that)

100Hz is ONLY for those whose eyes can't handle the amount of flicker displayed from a 50Hz refresh rate. Usually if you get headaches from watching for a long period of time, it means the refresh rate is too low for brain to handle. This does not mean you're an invalid in anyway. Some people are just more sensitive to it than others, that's all.

There is no other reason why you would want 100Hz. It doesn't give you a better picture or a better resolution, it just eliminates flicker.

100Hz at HD resolutions is just too impractical, given the amount of bandwidth required to refresh the screen at 100 fields per second.

There is a display that can do HD resolutions at up to 75Hz, which is excellent for eliminating flicker and still maintaining the excellent picture quality that HD brings, but I can't remember which display. You might have to search for it (I think it's the Rank Arena or something like that)

If your display can resolve HD (even 720 lines is better than any SD display), you don't mind the flicker (read: if you don't notice it on your current TV), and your viewing distance is optimal (if you sit too far, HD and SD will look very similar, if you sit too close you will get sick, but at the right distance, you will be able to discern the difference easily between SD and HD), then by all means go for a HD box.

However, if your can only resolve around 576 lines, you can't stand the flicker, and your viewing distance is greater than 2m for an 86cm TV, then stick with an SD box. Chances are, you will not notice a difference unless someone points it out to you.

ps. the difference between HD and SD is not just about the resolution but also clarity, crispness and colour.

[Tackler]

Once again guys, thanks for the advice! Been invaluable, especially for a novice such as myself.

Have posted a question regarding the pros and cons of a STB with PVR vs 2 separate pieces of equipment. Hopefully I can get some clarification on that issue as well!

All is all, it looks like I won't see MUCH difference if any with a SD vs an HD STB on the Lafinion tv, but it may be worth it in case there is a marginal difference and it may future proof me in case I upgrade the tv further down the track!

[Recon]

Those lafinion lg series accept a 576 Progressive Signal, but when it is in 576P it is no longer a 100hz TV, it is a clearer picture, but you start to notice the flicker.

When it runs on a 576i signal it defaults to 100hz and there is no way to force progressive like you can on the likes of say panasonic.

Running a HD set box would improve picture slightly, but so would a decent model SD box that can output component signal rather then RCA/Svideo, as the lafinion has twin component inputs.

[firestorm]

  DavoNogo said:

There is a display that can do HD resolutions at up to 75Hz, which is excellent for eliminating flicker and still maintaining the excellent picture quality that HD brings, but I can't remember which display. You might have to search for it (I think it's the Rank Arena or something like that)

<{POST_SNAPBACK}>

It was a Panasonic TX-76PW300A. The 75Hz refresh mode is there to eliminate blur that you get with 100Hz refresh rates during fast motion scenes.

Like other TV’s it can only run the higher refresh rates in interlaced mode. In progressive scan mode the refresh rate is the standard 50Hz.

[DavoNogo]

  firestorm said:

Like other TV’s it can only run the higher refresh rates in interlaced mode. In progressive scan mode the refresh rate is the standard 50Hz.

<{POST_SNAPBACK}>

The Sony KVHR36M31 can go up to 60Hz on all HD resolutions, which helps to eliminate the flicker, but doesn't completely remove it as much as 100Hz or 75Hz. Oh yeah, and both 75Hz and 100Hz help with motion, but the main aim of higher refresh rates is to remove flicker.

[JSmith]

  Mr_Gimlet said:

Back in my pre-plasma days (ie two weeks ago) I had a Loewe Calida which is one of the better quality CRTs available out there. When I first got into DTV, which was because of my crap analogue reception, I actually found the SD boxes were outputting what to me looked a better picture. Now things have moved in since my clunky Strong box, but I thought the HD picture was worse through my Loewe, and the extra money for HD swung it.

In technical terms, I am not your man - but my basic understanding is that all CRTs are SD, some with better pictures than others. I am open to correction.

<{POST_SNAPBACK}>

JSmith :ph34r:

[AlexF]

  jsmith said:

   

JSmith  :ph34r:

<{POST_SNAPBACK}>

It's not so funny. All he had to say was "majority" rather than "all" and he'd be 100% right.

Besides, with the number of NTSC-resolution Plasmas out there, perhaps one can also conclude that majority of plasmas are sub-par (PAL) SD also.

[I am not a duck]

I have the LG Lafinion 82W and would not recommend it. Purchased because the price was right, and it has a lot of inputs, there is a problem when used on either component input.

1) When watching some purchased/rented DVD's the sound level on some programme material drops to about half in a cycling effect that can be quite annoying.

2) intermittently the screen loses sync, blanks out and then returns, giving the impression you have just changed between sources using the MULTIMEDIA function on the remote.

The set runs with a LG RH7521W DVD/HDD recorder, and the problem does not occur when used in the AV mode.

I've since learned this is a problem with this model. I'll live with it, although not happy, as the set is a stop-gap until upgrading to a different technology.

[DavoNogo]

There are probably only around 5-6 models of HD CRTs in the country out of the many hundreds, if not thousands of regular CRTs out there.

[TreeFern]

  marcj said:

I have the LG Lafinion 82W and would not recommend it. Purchased because the price was right, and it has a lot of inputs, there is a problem when used on either component input...

marcj,

Please see my previous post regarding a possible fix for the audio surges on Component 1 of the Lafinion 82W.

http://www.dtvforum.info/index.php?showtop...ndpost&p=238512

Tackler,

If you only want to watch SD, then the Lafinion is pretty good I reckon. Nice (SD) PQ with excellent skin tones. Great sound and a stylish, easy to use remote that impresses one's wife. Problems only arise when you want to input a progressive signal via Component 1. Component 2 is OK (and only accepts progressive).

The first SD-STB I tried with this telly was an RCA TRC501AU link($165) connected via S-Video. PQ was pretty good. User interface was good. Unit was very small and nowhere as ugly and 80's looking as some other boxes. But the S-Video connection was on the side and so one could see the cable hanging there. Also I wanted to try the best possible connection. I tried component input from a couple of SD boxes (Teac and Nextwave) with SCART plugs, but didn't like the PQ (thought it worse than S-Video and the colour was bad). So I also tried an LG-5100 HD-STB ($450) with dedicated component RCA plugs. PQ was better but not sure if it warranted the extra cash. And since I also had a progressive DVD player, I started running into the problem marcj describes.

[JSmith]

  Alex said:

It's not so funny. All he had to say was "majority" rather than "all" and he'd be 100% right.

Besides, with the number of NTSC-resolution Plasmas out there, perhaps one can also conclude that majority of plasmas are sub-par (PAL) SD also.

<{POST_SNAPBACK}>

Dude he clearly said "all", I even highlighted it for you, sheesh Why do you care anyway, can't this other chap post a comment if he feels hard done by?

JSmith :ph34r:

[JSmith]

  DavoNogo said:

There are probably only around 5-6 models of HD CRTs in the country out of the many hundreds, if not thousands of regular CRTs out there.

<{POST_SNAPBACK}>

sure, but not all of those are 100Hz, which was the thread.

JSmith :ph34r:

[DavoNogo]

There are a lot more 100Hz CRTs than there are HD ones, and the quote you mentioned was only referring to the HD TVs, not TVs with 100Hz, so that "basic understanding" was off-topic anyway.

[Auste1234]

Hey guys,

We are the retailers who wrote that, and have that Ebay listing.

Yes there are a few HD CRT TV's, but they are far more expensive than $1,100.

I might have to get that little explanation on ebay updated, what it is meant to say is that quiet a lot of people buy a 100hz Tv thinking that 100hz means they get a true HD picture,. When it says all CRT Like this one it's meant to mean around this price range.

Sorry for that slight confusion, but like the add says, nobody else on ebay or few sites in general explain this.

Kind regards,

Kirk Austin

Doug's Electronics

[Auste1234]

Ok people the site has been updated. Hopefully this explains it a bit better.

Once again, sorry for the slight confusion

"We also want to touch on the myth of High Definition on 100hz TV's. Just because you buy a 100hz TV does not not mean it's HD! It doesn't matter what the adds says (unless the CRT TV costs $2,500), even if it does say it will do HD! You have to understand that CRT TV's only have around 576 lines. So you can't possibly get a true 720 or 1080 HD picture, it simply doesn't have the resolution to support this! It will however accept the signal! but because it doesn't have the lines/pixels to support this you are still only getting a standard digital picture. You might be wondering why we are telling you this? wouldn't this hurt sales? We think it's better to tell people the truth rather than to mislead you and say yer it will take HD, while the poor customer thinks they are watching true HD picture when in actual fact they are still only getting an up-scaled SD picture.

So in summary you might still be wondering what it all means, well this TV, and every other CRT TV in this price range will take the actual HD signal, but it won't display a true HD picture. You have to spend at least $1,800 or more to get a CRT TV with 720 lines. "

Is this better?

[RodN]

  Auste1234 said:

Ok people the site has been updated. Hopefully this explains it a bit better.

Once again, sorry for the slight confusion 

"We also want to touch on the myth of High Definition on 100hz TV's. Just because you buy a 100hz TV does not not mean it's HD! It doesn't matter what the adds says (unless the CRT TV costs $2,500), even if it does say it will do HD! You have to understand that CRT TV's only have around 576 lines. So you can't possibly get a true 720 or 1080 HD picture, it simply doesn't have the resolution to support this! It will however accept the signal! but because it doesn't have the lines/pixels to support this you are still only getting a standard digital picture. You might be wondering why we are telling you this? wouldn't this hurt sales? We think it's better to tell people the truth rather than to mislead you and say yer it will take HD, while the poor customer thinks they are watching true HD picture when in actual fact they are still only getting an up-scaled SD picture.

<{POST_SNAPBACK}>

Typical ebay rubbish (i.e lies) ..... the Sony's and Ranks will fully resolve over 1000 vertical lines, the pana's and toshiba's are not far behind.

[Auste1234]

No offence buddy but you don't know what your talking about, or you havent read what i said. I did not say none do them, what i am tying to say is there aren't a heap of them around..... and there isn't.... and the ones that are on the market are quiet a bit above $1,500.

The point of that is a lot of people have been told that all 100hz TV's will do a true HD picture, i tried to explain this is not the case.

Get some glasses