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Confusedofmaiden 27-01-2014 22:20

UHD tv and poor picture
 
Hi all, I'm new at this.
I've bought a new UHDTv and the picture is poor in HD mode and really poor in standard. I'm informed that virgin media cannot output in adequate format.(1080). Any advise? So many different opinions but no conclusive answers. Can anybody help

Kabaal 27-01-2014 22:29

Re: UHD tv and poor picture
 
You could build a time machine and watch TV from the future. Broadcast TV is only 1080i.

Congrats on being an early adopter of 4K TV :p:

OLD BOY 28-01-2014 14:04

Re: UHD tv and poor picture
 
Quote:

Originally Posted by Kabaal (Post 35666531)
You could build a time machine and watch TV from the future. Broadcast TV is only 1080i.

Congrats on being an early adopter of 4K TV :p:

Is there no way the OP can receive a decent picture using a Virgin box? Presumably it will be the same on Sky?

Kabaal 28-01-2014 14:11

Re: UHD tv and poor picture
 
As long as he has it set to 1080 in the set top box he isn't going to get any better. TV doesn't broadcast in resolutions higher than 1080i for now on any provider. I would have thought that most 4K TV's would do a decent job of upscaling content to it's resolution although it will never be a substitute for proper 4K content.

SD looks awful on normal 1080p 50" TV's IMO so it's no wonder that looks bad on his super duper ultra hd tv.

Also bear in mind that i think the smallest 4K TV is 55" with most of them being 65".

passingbat 28-01-2014 15:55

Re: UHD tv and poor picture
 
You should be OK when Netflix release the second season of House of Cards in just over two weeks time ---- providing your TV has a 4K Netflix app --- as that will be UHD.


Broadcast TV has to be upscaled, which effectively means (intelligently) guessing the value of the missing pixels. With SD at 720X576 pixels and UHD at 3840X2160, that's a heck of a lot of pixels to 'guess'. Even with HD at 1920X1080, there are still a lot of actual pixels missing.

Taf 28-01-2014 16:23

Re: UHD tv and poor picture
 
Damn... I was wondering why I could not get through on my subspace communicator..... I have to wait for the rest of the world's technology to catch up I suppose... :dunce:

martin201002 28-01-2014 16:55

Re: UHD tv and poor picture
 
Be a while before ultra hd is commonplace , hopefully it will fair better than 3d tech.

Kabaal 28-01-2014 16:59

Re: UHD tv and poor picture
 
Quote:

Originally Posted by martin201002 (Post 35666672)
Be a while before ultra hd is commonplace , hopefully it will fair better than 3d tech.

As long the prices keep falling to a reasonable figure that will get it into a lot of homes then it should. I saw a 4K demonstration in the Glasgow branch of Richer Sounds and it really does look fantastic compared to 1080p.

3D is something that people either love or hate and many see as a novelty, 4K is just a straight up much better quality image. It's more of a natural progression.

martin201002 28-01-2014 17:03

Re: UHD tv and poor picture
 
Quote:

Originally Posted by Kabaal (Post 35666673)
As long the prices keep falling to a reasonable figure that will get it into a lot of homes then it should. I saw a 4K demonstration in the Glasgow branch of Richer Sounds and it really does look fantastic compared to 1080p.

3D is something that people either love or hate and many see as a novelty, 4K is just a straight up much better quality image. It's more of a natural progression.

Yeah 4k it's the next evolution in television technology, I have a 3d tv the kids use it more than me. Gives me a headache.

passingbat 28-01-2014 17:43

Re: UHD tv and poor picture
 
Quote:

Originally Posted by Kabaal (Post 35666673)

4K is just a straight up much better quality image. It's more of a natural progression.

But with the lack of a reasonable amount of 4K content, which will be the case for a long time, as demonstrated by the OP, upscaled HD and SD may not look quite so good. This means the end PQ will depend on the quality of the TV's upscaler, and good upscalers don't come cheap.

TheDon 28-01-2014 17:54

Re: UHD tv and poor picture
 
Quote:

Originally Posted by passingbat (Post 35666651)
Even with HD at 1920X1080, there are still a lot of actual pixels missing.

Upscaling from HD to UHD is actually trivial as it's a simple doubling of the resolution.

If you look at the difference between a HD and UHD tv of the same screen size the difference is the pixels are 1/2 the width and height, so to "upscale" HD to UHD you simply use a block of 2x2 UHD pixels for each HD pixel and your picture should be no worse than watching a HD panel of the same size.

nicknewark 28-01-2014 18:23

Re: UHD tv and poor picture
 
I'd rather VM get the missing HD channels first, before we start on UHD!.

TheDon 29-01-2014 13:00

Re: UHD tv and poor picture
 
Quote:

Originally Posted by heero_yuy (Post 35666937)
That would be simple mapping rather than upscaling, more ambitious scaling would interpolate the intermediate pixels to rid the result of jagglies. Doesn't make more resolution but rids the upscale of the worst artifacts.

I have a 100Hz TV and the top end model of that range interpolates the "missing frames" to smooth out action.

Upscaling is simply the changing from one resolution to another, pixel doubling is by definition upscaling.

You will get the same amount of jaggies using pixel doubling from HD to UHD as you would viewing the HD content on a native panel of the same size.

Whilst you can use more advanced techniques to attempt to improve the picture my point still stands, the absolute worst case on viewing HD content on a UHD panel is that you get the exact same picture as you would have on a HD panel of the same size.

This is entirely different than viewing SD content on HD (or SD on UHD) as there is always the need to interpolate pixels when upscaling there.

There are no "missing frames" with upscaling. You 100HZ tv interpolates missing frames because of the difference between the refresh rate of the panel and the frame rate of the signal. It has nothing to do with upscaling at all, they're both entirely different concepts.

Stephen 29-01-2014 18:55

Re: UHD tv and poor picture
 
Quote:

Originally Posted by TheDon (Post 35666698)
Upscaling from HD to UHD is actually trivial as it's a simple doubling of the resolution.

If you look at the difference between a HD and UHD tv of the same screen size the difference is the pixels are 1/2 the width and height, so to "upscale" HD to UHD you simply use a block of 2x2 UHD pixels for each HD pixel and your picture should be no worse than watching a HD panel of the same size.

Is it, I thought all the 4K and UHD stuff states its 4 times the resolution of HD?

Anyway wtching HD on a UHD screen is never going to look great. Was the same when SD on HD first came about and people moaned that it looked rubbish.

TheDon 29-01-2014 20:34

Re: UHD tv and poor picture
 
Quote:

Originally Posted by Stephen (Post 35667104)
Is it, I thought all the 4K and UHD stuff states its 4 times the resolution of HD?

Anyway wtching HD on a UHD screen is never going to look great. Was the same when SD on HD first came about and people moaned that it looked rubbish.

Twice the resolution, 4 times the pixels, they're generally advertised at having 4 times the detail, which refers to pixel count.

SD on HD is an entirely different kettle of fish to HD on SD, SD on HD you have to guess pixels, they don't fit nicely.

The problem most people looking at HD content on UHD panels have is they're going from a 40 to 60 inch panel, and it's that increase that kills the picture, not having 4x the pixels.


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