A Question about 720p

Discussion in 'General TV Discussions Forum' started by harvest1, Mar 26, 2006.

  1. harvest1

    harvest1
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    A question:

    NTSC is 525p

    PAL is 625p

    So surely 720p is only as much of an improvement over 625p, as 625p is over 525p.

    Or am I going mad!
     
  2. dan1979

    dan1979
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    720x480
    720x576
    1280x720

    are the actual resolutions.
     
  3. Stephen Neal

    Stephen Neal
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    You're (understandably) confusing the total number of lines with the active number of lines. 525 and 625 refer to the total number of scan lines in the 60Hz and 50Hz standard def TV systems - however not all of the lines contain picture information. However the 720 of 720p refers just to the number of lines that contain picture information.

    For a more accurate resolution comparison :

    480i = 720x480 = 525i
    576i = 720x576 = 625i
    720p = 1280x720 = 750p
    1080i = 1920x1080 = 1125i

    The first figure is the number of "active" lines - i.e. the number of lines that contain picture information. The second figure is the regular horizontal and vertical resolutions (though there are variants on these).

    The final figure is the total number of lines - including those that don't contain picture information.

    Also "NTSC" and "PAL" are interlaced - so 525i/480i and 625i/576i respectively. (NTSC is not 525p and PAL is not 625p - they are 525i and 625i...)

    480p/525p and 576p/625p are really limited to progressive DVD replay. (480p was used in the US for Fox ED Widescreen broadcasts - though these were usually 480i to 480p conversion, but Fox have ditched this in favour of 720p now...)
     
  4. Ray

    Ray
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    Always wondered why my pj reported 750p and 1125i - now I know. Thanks Stephen. :thumbsup:
     
  5. chedmaster

    chedmaster
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    And Xbox 360 which looks amazing in 480p :)
     

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