If I capture a paused frame from TV, how many seconds does that count as?

Discussion in 'Playback Devices' started by Don Black, Jun 27, 2004.

  1. Don Black

    Don Black Screenwriter

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    Given that NTSC is 30fps (29.97), if I pause a TV show and capture that paused frame, is that really 1/30th of one-second of the show?

    Thanks!
     
  2. ChrisWiggles

    ChrisWiggles Producer

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    Logic would seem to indicate so....:b
     
  3. Don Black

    Don Black Screenwriter

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    I would think so too. But I thought that a "pause" maybe somehow interposed multiple frames or something weird...
     
  4. Robert Cowan

    Robert Cowan Supporting Actor

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    depends on the pause feature.

    if its a frame you paused on, you got 1/30 of a second. if you paused on a interlaced field (1/2 of a frame), you did 1/60th of a second.
     
  5. Don Black

    Don Black Screenwriter

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    Robert,

    Is it possible to pause on two frames at the same time (or 4 interlaced fields I guess)?

    Thanks.
     
  6. Allan Jayne

    Allan Jayne Cinematographer

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    Pause might give you two fields (or one frame's worth) of video depending on the system. There is no guarantee that the two fields will match in terms of subject position or motion. If the pause gives just one field, the even scan lines put on the screen are duplicates of the odd scan lines.

    On a VCR, during pause, the diagonal path the head makes across the tape is not quite the same angle the head makes during normal play. This results in the head spanning more than one recorded track where one recorded track corresponds to one video field. There is also a discontinuity when the head crosses from one track to the next so you may see the picture split into three of four horizontal bands. The better VCR's use four or six heads to scan the tape during pause, and blend things to give a smooth still frame but still, several fields contribute to the picture as seen and blur due to subject motion may be noticeable.

    Video hints:
    http://members.aol.com/ajaynejr/video.htm
     

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