Why are 576i signal from Sky HD box worse than Sky+

Discussion in 'Sky Digital TV Forum' started by tiger123, Jun 27, 2015.

  1. tiger123

    tiger123
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    The PQ of a 576i channel from a Sky+ box is far better than SD channel outputted in 576i from a Sky+HD box. Why is this?
     
  2. pedro2000uk

    pedro2000uk
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    Cut down chip set processing probably focussed/ optimised for HD & just legacy code for SD

    have a look at this thread - sort of related
     
  3. davemurgatroyd2

    davemurgatroyd2
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    How is the HD box connected? If by HDMI then you have an additional step in processing signal and possibly downscaling in TV. Scart input from SD box will probably be better optimised as well.
     
  4. Member 719122

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    This can be frustrating and the picture is like watching a bad movie with low compression. You could try swapping from Sky + to Sky HD + and the SD channels should increase in quality and improved bit rates.
     
  5. kevkbuk

    kevkbuk
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    Please explain how that works when the same SD channel is broadcast to each box hence the same bit rate.

    The difference as already discussed comes from picture processing and scaling.
     
  6. Member 719122

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    I've passed this onto our tech tech as this one is a little above my head! :* Jenny
     
  7. grahamlthompson

    grahamlthompson
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    I have a theory.

    The HD box is obviously connected by HDMI. I reckon the Sky SD box is connected by scart using CVBS connections rather than RGB. I reckon a fully wired scart cable connected to a RGB capable scart socket and selecting RGB rather than composite output would make a big difference (possibly even better than the Sky HD box if the TV has a decent quality scaler).
     
  8. grahamlthompson

    grahamlthompson
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    SD box connected using only composite video yuk :) ), HD box using digital RGB or digital component via HDMI. ??

    Simple way to tell - connect the Sky-HD box to the scart cable the SD box is using. At a guess it will look equally poor on SD sources.
     
    Last edited: Jul 9, 2015

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