Sky HD resolution question

[islandman]

Just had Sky HD installed and have a question on resolution settings.

TV is a 37inch Samsung about 18 months old so HD Ready (720p) & not 1080i.

Sky box is set at 1080i and although I can change this to 720p when doing this I can't see any difference in the quality --- which is excellent.

Does it matter which setting I have the Skybox on? ---- most likely not as both are just as good. However does it mean that if I bought a 1080i TV & put the 720 upstairs, I'd get even better quality?

Cheers for any help.

 

[GaryB]

If the TV has the HD Ready logo on it, then it must accept 1080i. It's a requirement of the HD Ready standard. I would be very surprised if any TV sold 18 months ago, assuming it's a UK model, couldn't accept 1080i. Sky broadcast their HD channels in 1080i, so sticking to the same resolution throughout out is generally best, as the Sky Box won't then have to scale the picture.

 

[FourFootMedia]

If the TV has the HD Ready logo on it, then it must accept 1080i.

However, the set could still be fitted with a 720 panel, it accepts the 1080 signal, then scales it down to fit the 720 panel. I believe this is still allowed by the "HD Ready" reccomendations.

Probably best to leave it at 1080i (or even better - auto, so for HD broadcasts it'll output 1080i and for SD 576p) as the scaler in your TV will more than likely be better than the one in the sky box.
If you get a TV with a 1080p panel then you *might* notice a difference, depends on the size and how far away you sit (and how good your eyesight is!). For example a 42" panel and sitting <6' away you may notice a small difference between 720p and 1080i.

 

[GaryB]

However, the set could still be fitted with a 720 panel, it accepts the 1080 signal, then scales it down to fit the 720 panel. I believe this is still allowed by the "HD Ready" reccomendations.

If it's an LCD, it won't be a 720 panel. It will be either 768 (1366x768) or 1080 (1920x1080). In any event, the point is that if it has the HD Ready Logo, it will accept a 1080i signal. If it doesn't, either it's faulty or someone at Samsung has a bit of explaining to do.

Most TVs display some sort of picture disturbance when switching between 576/720/1080, so it's best to lock the STB to one resolution to avoid this. Sky's default with all recent STBs is to lock the HDMI output to 1080i specifically for this reason.

 

[islandman]

Thanks for the replies.

Having tried 1080, 720 & auto I can't really see any difference --------- All excellent quality. If I had to choose one I'd go 1080 but that may just be imagination!

Talking of imagination ------- the SD quality now does seem bad (against HD) possibly worse than it was on the previous Sky+ ordinary box. Could this be true?

 

[ChrisFrost]

As fourfootmedia already said, (and I'll paraphrase) the Sky HD box is absolutely **** poor at converting SD channels to 1080i or 720p HD. When you set the box to 1080i or 720p that's exactly what you force it to do for non-HD channels.

Leave the box set on auto. It should default to 1080i output for HD channels and 576i for SD. This is the best way forward.

Just for the sake of completeness, 720p should never be used unless absolutely necessary. All Sky's HD content is 1080i. The box does a lousy job of converting 1080i to 720p.

 

[lynthan911]

Hi guys new to the forum so go easy!
I have my sky hd box set to 720p as this is superior to 1080i since an interlaced signal is prone to flicker where as a progressive signal scans the whole picture at once. Also 720p handles fast motion better than 1080i so is better for sports. How ever if you have yours set to auto and you are happy with the results then thats what i would stick to. Hope this helps

 

[ChrisFrost]

If 720p works best for you on your TV then that's great. Not every TV is going to respond the same way, and although most of find that 1080i is best for HD from Sky there's bound to be exceptions to the rule. It's worth clarifying a couple of points though just to avoid any confusion for other readers of this thread...

"720p is better for sports" - That is true as long as the footage was video'd at 720p and broadcast at 720p. All of Sky's content is broadcast at 1080i (regardless of how it was video'd) so much of the advantage of 720p is lost.

"interlaced is prone to flicker"
- If you are talking about the sort of whole image flicker that we used to see with 50Hz CRT TV then that can happen with 720p as much as with 1080i.

- Alternatively, if you are describing line jitter (fine horizontal lines jittering up and down) then unless you have an older ALiS panel plasma TV it's more likely to be down to a TV menu setting being wrong or the TV struggling to deinterlace properly.