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native rate

Discussion in 'Plasma TVs' started by peter350, Feb 27, 2003.

  1. peter350

    peter350
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    I have some tricky questions for you plasma gurus.

    I am thinking of buying a pioneer 50" 503mxe and running it at its native rate with a scaler.

    According to the specs the pioneer accepts its native rate via rgbhv at 56, 60 and 70 refresh rate and via dvi at 56 and 60.

    Does it also take 50 or 75 at native rate? If not how does it manage pal (as a conversion by the scaler from 50 to 60 is not great)?

    I understand that the unit's native rate of 1280 x 768 is not exactly 16:9 and this requires some action on the part of the scaler to ensure proper aspect ratios. Anyone know if my scaler (a rock+) does this Ok.

    Thanks Peter
     
  2. MarkTaylor

    MarkTaylor
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    If the Rock+ doesn't have 1280x768 as a standard resolution you should still be able to set up a customer resolution to handle it I would have thought.

    Do be careful though, driving pioneer plasma's with external native rate scalers has caused a few problems for people over the years mostly down to the way that the Pioneer does it's own internal frequency conversion.

    The Faroudja NRS for example had a lot of problems with the Pioneer trying to drive it at 60Hz. Most reports that I've seen suggest that driving it at 70 or 72Hz is much more likely to produce a good clean image. Most common issue reported at 60Hz was 'tearing', particularly during fast pans.

    There is a lot of Rock experience out there on other boards (particularly in the USA), you should be able to find plenty of people able to confirm or deny any Pioneer issues.

    Mark
     
  3. peter350

    peter350
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    Thanks Mark that's very informative as I had assumed that Ntsc would be ok as 60hz was permissible. It seems that one needs 72 for Ntsc and 75 for pal.
    If anyone knows what refresh the pioneer can manage at native rate (via rgbhv and dvi) I would be grateful.
     
  4. MarkTaylor

    MarkTaylor
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    If you are feeding the plasma at native rate then you are intending to give it a computer type signal not a video signal so issues like PAL and NTSC shouldn't come into it.

    Internally the Pioneer will convert those signals to something around 70Hz even if you were feeding it a video signal.

    Accoring to the Technical manaul for the 503MXE it supports 1280x768 at 56/60/70Hz that will be via the VGA/RGBHV interface though not the the DVI.

    DVI only supports 56 and 60Hz.

    Mark
     
  5. peter350

    peter350
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    Ah, the scales fall from my eyes: the pioneer always outputs 70hz and so native rate has to be 1280 x 768 at 70hz.

    I suppose this makes dvi not that useful for an external scaler.


    One point though: doesn't the conversion from video material at 50 or 60 hz to output at 70hz (whether done internally by the pioneer or externally by a scaler) create artefacts as 70hz is not a multiple of 50 or 60 hz nor of the variants suitable for Ntsc film sourced material such as 72hz?

    Peter
     

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