Is Sky HD 1080i or 720p or both?

Blaster99

I'm trying to figure out what HD TV to buy to work with Sky HD. There's quite a bit of stuff on the 'net about this but it's all "we think Sky will do this and that" but very little about the actual service being delivered today. I guess the question is simply, should I go for a 1920x1080 set to get native 1080i (or indeed p) support, assuming some or all of Sky's content is in 1080i?

JDxtra

It's both...

Blaster99

Is there such a thing as a list of HD channels (on the Sky platform) and their resolution anywhere?

watty

Yes, but I forget where.

Basically:

BBC HD trial
Nat Geo HD
Discovery HD
Sky HD (much non HD content, A)
Sky Sport (Not sure how many)
Sky Movies (Not sure how many)
Artsworld HD

Maybe a Sky Box office HD? Not sure.

Most real HD content is 1080i
Some sport may be 720p

Due to differing horizontal resolution and 1080i sends 540 lines at a time 1920 wide, both HD modes are the same Bandwidth. 1080p is exactly twice, so may never be used by broadcasters internally nor on broadcast. 1080p is really for computer games.

AFAIK
ON 720p mode the Skybox downsamples 1080i and converts to progressive.
On 1080i the box outputs 1080i or 720p, which ever is transmitted. i.e. does nothing.
HD has no 4:3 mode, all 4:3 material on HD has "curtains" at sides. HD thus has no WSS signalling.

Cf WS & 4:3
On WS the box does nothing, 4:3 OR 16:9 IS Output as is
On 4:3 Letterbox, it resamples 16:9 vertically to letterbox and leaves 4:3 as is.
On 4:3 Crop (P&S) it chops sides and resamples horizontally to fill the screen again. 4:3 unaffected.

ixtlan

Hi all,

Actually my understanding is that everything SkyHD broadcasts is in 1080i. If you select 720p the box downsamples as Watty has said, otherwise it passes it through to the TV.

On the avforums website many people are of the opinion that it's better to leave the box in 1080i or auto. This is because it removes one scaler... 1080i->720p>768p better as 1080i->768p. It also is Sky's preferred setting.

Of course what you really want to know is whether it's better for you to buy an expensive 1080 panel rather than a 768 one. That depends on screen size, viewing distance, and your available funds. There's no doubt 1080 is "better" but at normal sizes 40" or under, and viewing distances of 8ft+, it is debatable how much better it will be. avforums has had many debates along these lines.

1080 screens are just now appearing on the market in numbers but still have a premium price. Personally I'm in the fortunate position of being able to wait until next year to buy. However even then I might go for 768 if it's a good bargain, knowing that I might upgrade again in maybe 3 years.

It's a tough call, and most TV shops are not going to be able to properly demonstrate the 768/1080 difference.

Ix.

byte

watty wrote:

Yes, but I forget where.

Basically:

BBC HD trial
Nat Geo HD
Discovery HD
Sky HD (much non HD content, A)
Sky Sport (Not sure how many)
Sky Movies (Not sure how many)
Artsworld HD

Maybe a Sky Box office HD? Not sure.

Yes there is Sky Sports HD1 and HD2
Sky Movies 9HD and 10HD

Sky Box Office has 2 HD offerings - SBO HD1 and SBO HD2.

Ulsterman 1690

Most real HD content is 1080i
Some sport may be 720p

I remember hearing somewhere that some American networks broadcast ALL their content in 720p

watty

However that is just a rumour. Apart from sport the bulk is 1080i. Same bandwidth but sharper picture on your 72" TV. Only a disadvantage on sport, hence 720p for sport.

Conviently when things are moving quickly you can't actually SEE as sharply! So it is a good technical compromise.

watty

Toshiba do a laptop with 1920 x 1200 screen HD DVD play, DVD dual layer/CD write/Play and Hybrid Analogue and Digital TV tuner built in. Works as TV or DVD/CD/HD player without booting windows.


IX is right. Leave Skybox at 1080i and let the TV do it. And REAL FULL HD resolution sets are thin on ground. 1366 x 768 is most common.

Blaster99

What's the story with 768? It's neither 1080 nor 720 so it can't display anything natively. Or what am I missing?

I saw a Samsung 40" 1920 x 1080 for about €2,600 somewhere, so they're getting there price-wise.

pH

I have Sky HD (on a Panasonic AE900) over HDMI. It's set to auto.

All 4:3 broadcasts appear stretched, the Sky box doesn't seem to put black bars down the side. I have to use the remote for the PJ to change aspect ratio.

Also, all the PAL SD stuff is converted to progressive. Sky's deinterlacer is not as good as the one in the panny, often scrolling text over HDMI appears jagged, whereas if I stitch to the RGB SCART, the panny does a better job at deinterlacing.

I've seen nothing broadcast so far in 720p, it's all been 1080i as far as I can tell.

ixtlan

Blaster99 wrote:

What's the story with 768? It's neither 1080 nor 720 so it can't display anything natively. Or what am I missing?

I saw a Samsung 40" 1920 x 1080 for about €2,600 somewhere, so they're getting there price-wise.

Indeed, also a question frequently asked. Why are TVs 768 when the (lower) HD standard is 720. The usual answer given, which I assume has some truth, is that it's due to that being a standard PC monitor size, and that's what the factories are geared towards. Certainly it's far from ideal as it forces the TV to rescale the signal, though for SkyHD it would have to anyhow since everything is 1080i.

Yes, those 1080 TVs are getting cheaper. As well as the Sony X series, and the Samsung you mention (you must have seen it on Komplett!), there are some Sharps on the way and a Toshiba. Even so they are all going to sell at a slowly diminishing premium to 768 screens.

Right now I would not pay that premium... though the Samsung is getting close to where I might consider it.

Ix.

watty

1024 x 768 = XGA 4:3, 1366 x 768 = Wide XGA, though about six different resolutions are called "WXGA" some are really Wide SVGA as they have 800 lines