HD TV specs

[Frank]

Ok, I know it needs a digital interface and decode logic. But I really wonder about most aspects of all those "HD ready" TV's offered for sale. To me, they're not! And the Dutch consumer platform has sued a large retail chain for putting those stickers on lots of TV's that are definitely not HD ready in any way. Even if they have a functional digital interface and decoder.

What specs do we want for the display of a HD-ready TV? According to the specs, we want at least 720 lines, but really 1080 for full compliance (1920 * 1080). And, there are exactly no TV's for sale who have even 720 lines, let alone 1080.

Even worse, the largest models often have a staggering 480 lines...

And all the best ones only go as high as 1366 * 768. So, they are going to stretch the picture, whatever mode you use (720 or 1080). And you can see that, if you can find one that is hooked to a real HD TV source that is. And none of them look crisp, with a wide quality variance. Although you might not notice on the best ones from a distance of 3+ meter.

So, if you want to buy one, what specs would you want for good quality? It seems the most important thing is still how well it can stretch the picture, even with a real, digital HD TV feed.

 

[3dcgi]

Of course there are some TVs with exactly 1280x720 pixels. Not that I've counted the pixels, but manufacturer's like Sony make the claim on some models. I believe most DLP sets are native 720p.

HD-ready should mean it can display a high definition signal (greater than 480p), but lacks an integrated tuner. This isn't a problem if you use a cable box. I don't even use the tuner integrated into my TV but it's nice to have since I may need it in the future for some reason.

 

[pascal]

Stretching is important as part of a larger Image Signal Processing problem.
See this link about Sony´s DRC circuits: http://babelfish.altavista.com/babe...atch.impress.co.jp/av/docs/20060601/sony1.htm

Contrast and color range are also other important issue.

 

[oddfellow]

As far as I can remember (I'm sure Google will help), HD standards in Europe are set by EICTA.

Off the top of my head, their requirements are:
720p 50hz
720p 60hz
1080i 50hz
1080i 60hz
HDCP enabled DVI or HDMI input
Component YPbPr for analogue HD devices.

Edit:
My HD 45" DLP is 1280x720 native, so it can do "proper" 720p and 1080i. I also have a 27" LCD in my bedroom. It's labelled as HD ready, and does indeed accept HD signals, but I'm unsure about it's actual native resolution.

 

[Moloch]

As far as I can remember (I'm sure Google will help), HD standards in Europe are set by EICTA.

Off the top of my head, their requirements are:
720p 50hz
720p 60hz
1080i 50hz
1080i 60hz
HDCP enabled DVI or HDMI input
Component YPbPr for analogue HD devices.

Edit:
My HD 45" DLP is 1280x720 native, so it can do "proper" 720p and 1080i. I also have a 27" LCD in my bedroom. It's labelled as HD ready, and does indeed accept HD signals, but I'm unsure about it's actual native resolution.

Proper 1080i with 1280x720 pixels

 

[oddfellow]

Yeah, apologies for the brain fart. Obviously 1080i is interlaced, but I'm not sure about actual vertical line resolution. Can't see it being 1920, but it's possible I guess

 

[Moloch]

Yeah, apologies for the brain fart. Obviously 1080i is interlaced, but I'm not sure about actual vertical line resolution. Can't see it being 1920, but it's possible I guess

1080i is 1920x1080

 

[Tahir2]

Sometimes it is 1440 by 1080i and in some cases even 1280 by 1080i.

 

[Moloch]

Sometimes it is 1440 by 1080i and in some cases even 1280 by 1080i.

yep.. damn commies

 

[oddfellow]

1080i is 1920x1080

I know. I was saying that I'm unsure what my DLP's actual resolution is when displaying 1080i.

Wasn't clear. My bad.

 

[hey69]

well, most 720p sets and 1366x768 sets can display also 1080i .
(probably its ALWAYS rescaled to the native resolution anyway ....)

 

[Skrying]

Is 1366x768 a true HD specified resolution?

HD resolutions are VERY confusing, I've talked to many because they have no real idea what's best, what really is HDTV and what specs they should be really concerned about. I'm in this same ballpark because the majoirty of TV's I see that say they are HDTVs are 1366x768 and not 1280x720 or 1920x1080.

 

[3dcgi]

Is 1366x768 a true HD specified resolution?

HD resolutions are VERY confusing, I've talked to many because they have no real idea what's best, what really is HDTV and what specs they should be really concerned about. I'm in this same ballpark because the majoirty of TV's I see that say they are HDTVs are 1366x768 and not 1280x720 or 1920x1080.

I agree that HDTV is confusing and I don't believe anything is broadcast in 1366x768. My advice to people is to find a set that looks good to them in the store and buy it. Most HDTVs look great to people once they get home. With nothing else to compare to the average person doesn't notice anything that might be "off".

 

[Frank]

I did find some sets that are "real" 720 or 1080, and some of the 720 ones are (strangely enough) even cheaper than the competition, while looking better. Probably because most consumers don't know, and the numbers are lower... Although the 1080 ones are *very* expensive.

But I agree with Skrying that it's very confusing, and rather hard to make a good decision at the moment. So I'm recommending people to wait and see. It's not as if there are many HD TV sources at the moment, but it might make things hard for people who want to buy one right now.

 

[Moloch]

Is 1366x768 a true HD specified resolution?

HD resolutions are VERY confusing, I've talked to many because they have no real idea what's best, what really is HDTV and what specs they should be really concerned about. I'm in this same ballpark because the majoirty of TV's I see that say they are HDTVs are 1366x768 and not 1280x720 or 1920x1080.

has something to with it being like 1024x768 but with more horizontal pixels.. so its like easier to make or something

 

[Frank]

Good question! *WHY* did they come up with that stupid resolution of 1366 * 768 in the first place? It's just stupid.

 

[Xentropy]

Good question! *WHY* did they come up with that stupid resolution of 1366 * 768 in the first place? It's just stupid.

Hmm, not sure, but I think it's related to the NTSC and PAL video resolutions. 768 is 4/3'rds the PAL resolution of 576 lines, and 8/5's the 480 line NTSC resolution. Probably makes it easier to scale from both if it's a simple fraction between the different modes.