VHS is a smoother picture. Some freeview channels are so nasty you see artifacts jumping/crawling about the screen. Sky News is one of the worst. When they are reading from the news desk, their outlines are starting to separate because the picture is so small. You see all these vertical joints throughout the picture. It's like Youtube 2001/02.
BBC testing UHD.
- Thread starter GAC
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VHS is a smoother picture. Some freeview channels are so nasty you see artifacts jumping/crawling about the screen. Sky News is one of the worst. When they are reading from the news desk, their outlines are starting to separate because the picture is so small. You see all these vertical joints throughout the picture. It's like Youtube 2001/02.
When freeview started back in 2002 the picture quality was far superior then compared to what it is now ok we have the HD channels but im talking about the SD ones 
They had to reduce the bandwidth to fit all the extra channels in over the years so now most of them look really poor.
They had to reduce the bandwidth to fit all the extra channels in over the years so now most of them look really poor.
Associate
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Freeview quality is dismal these days.
How many more channels do they want to cram in ?
How many more channels do they want to cram in ?
We moved to HD last summer at an enormous cost. The company are likely to want that investment to last a fair few years. Similar to Phoenix, we have also only just moved to file based transfer, though we upgraded from SD based DigiBeta/DVCAM workflows.
Working in the industry, I can say that I don't really want to have to work with 4k. HD requires enough storage space and workstation power as it is. At 50mbps 1080i you'd be surprised to see how fast we can eat through the 160TB of storage space we have. Most of the mainstream network programmes are done at 120mbps or 185mbps 1080i. Plain storage may be quite cheap, but avid certified storage like their isis frames are not. Conversion times are also a pain in the neck, even with twin socketed 12 core xeon servers with 128GB of ram. (and with live tele, everyone wants everything yesterday)
Then there is the issue of satellite truck links as we moved from Ka band for SD to Ku band for HD, meaning a jump from ~14GHz uplink to ~40GHz. The result is that rain attenuation is far more severe causing more disrupted live links.
Leave 4K to the movie industry.
Working in the industry, I can say that I don't really want to have to work with 4k. HD requires enough storage space and workstation power as it is. At 50mbps 1080i you'd be surprised to see how fast we can eat through the 160TB of storage space we have. Most of the mainstream network programmes are done at 120mbps or 185mbps 1080i. Plain storage may be quite cheap, but avid certified storage like their isis frames are not. Conversion times are also a pain in the neck, even with twin socketed 12 core xeon servers with 128GB of ram. (and with live tele, everyone wants everything yesterday)
Then there is the issue of satellite truck links as we moved from Ka band for SD to Ku band for HD, meaning a jump from ~14GHz uplink to ~40GHz. The result is that rain attenuation is far more severe causing more disrupted live links.
Leave 4K to the movie industry.
Does that include BT TV though. Reason I ask is on the Sky Box that highest is 1080i but on the BT TV you can set it to 1080p. Does that mean BT's internet channels are 1080p?
I did a comparison on the same tv between my Sky HD and BT TV box and the BT TV HD picture was noticeably better. It was sharper and faces looked more detailed as though the bitrate on BT was higher.
I suspect that's purely the output from the box and up scaled.
One of the reasons sky don't broadcast in 1080p is it would effectively need double the bandwidth for a minimal increase in bandwidth.
Soldato
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There's a new codec called Perseus that is gaining quite a bit of traction in the industry, if it gets enough adoption you'll be able to broadcast an SD channel with the bandwidth of a radio station, HD in the same space as an SD, freeing up a huge amount of bandwidth for UHD, which will use about the same bandwidth as HD.
It's got a lot of interest with the broadcasters as they will be able to use it on their current set top boxes through an OTA firmware update. You'd still need a new box for UHD due to the HDMI requirements but everyone would benefit.
Be interesting to see what happens in the next couple of years.
1080i at 50hz uses the same bandwidth as 1080p at 25fps and you can carry 1080p/25 in a 1080i/50 stream, something called PsF (progressive segmented frame). 50i consists of two interlaced fields. 25p can be split into the two fields but when your TV plays it back the processing shows both fields at the same time giving you a progressive image.
Sky broadcast at 1080i for legacy reasons and back compatibility with an SD 50hz CRT.
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Whilst that is partially true, interlacing is used to improve the perceived motion smoothness as 25p is not entirely comparable to 50i. The problem is that since the demise of CRT, few home devices utilise the old fashioned electronic scanning meaning everything gets de-interlaced prior to display affecting not only the way it looks but also the apparent smoothness. 50p is the way to go as you get both the motion smoothness of 50i and the vertical resolution of progressive but it then costs you bandwidth, hence why 50i is considered to save on bandwidth.
We shot and edited one programme at 25p instead of 50i to satisfy the producers curiosity. Whilst the pictures looked superb (PMW-F5 with primes), the motion was too flickery for fast moving subjects or pans. It would be far too time consuming to add & render motion blur as an effect in post when using 50i solves the problem with no time penalty. (plus you can't apply effects to live shots) Viewing interlaced content on a proper grading monitor like a Sony PVMA250 or JVC DT-R24L41D shows what it is supposed to look like. (butter smooth)
I can't disagree that change is necessary but 25p is not it. I'd rather see 1080p/50 than 4k but I can't realistically see either happening for a good decade or so due to infrastructure requirements.
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Soldato
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You're right, I was more making the point that people aren't losing out with a 1080/50i broadcast if the source material is 25p. A film for example is shot at 24p, sped up to 25p and then broadcast at 50i so you don't lose anything.
If a programme is true 50i then you are affectively losing out because the TV has to deinterlace it so yes this is where you'd want 50p or 100i, which isn't going to happen for broadcast 1080.