4 ms·

The article discusses exactly this, so I'm not sure what your issue is.

protomyth 14y ago
It talks about scan lines and 3:2 pull down but does not mention an actual film projector displays the whole frame at once where TV's have scan lines.
- zaphar 14y ago
  He discusses the difference between 1080i and 1080p which is exactly the difference you are talking about. Interlaced vs whole frame. Not all TV's have scan lines. Any that are 1080p do not interlace.
  - protomyth 14y ago
    You and the person voting me down seem to be missing the point of what I'm saying. A piece of film is illuminated and shown fully on the screen. There is no scan line. A TV is drawn one line at a time. There is a scan line. Interlaced vs Non-Interlaced has nothing to do with what I am talking about as both draw one line at a time. Interlaced just means it draws half the first tick and half the second tick. Non-interlaced draws the full frame each tick. Both draw a line at a time.
    - __david__ 14y ago
      No, NTSC on a CRT is drawn one line at a time (it is physically scanned by the electron gun). But TV is not NTSC any more and CRTs are dead/dying. Your HD flatscreen (plasma or LCD) does not draw one line at a time. HD is decoded into a framebuffer and that framebuffer is drawn on the screen in some hardware specific way. It may be rectangles, or the whole screen, or different vertical/horizontal slices (with very high refresh rates so you don't see flicker). Edit: Moveover, "film" is almost always digital nowadays (I don't think I've seen a non-digital projection in the last 5 years) which means that the picture gets to the screen via some form of LCD projection. So your home TV and film are basically the same at this point. You would've been right 10 years ago, though.
    - shardling 14y ago
      I accidentally downvoted your original post, but of course there's no way to reverse that. :( (Some of HN's design baffles me.)
    - ars 14y ago
      That's not true. A film projector has a moving shutter - only part of the image is visible on the screen at a time. You can prove it by using a camera with a fast shutter and trying various shutter speeds. If you have a leaf shutter in your camera you'll have to hold the camera in all 4 direction to test it properly - you don't want the projector shutter and the camera shutter to interact weirdly.

It talks about scan lines and 3:2 pull down but does not mention an actual film projector displays the whole frame at once where TV's have scan lines.

zaphar 14y ago
He discusses the difference between 1080i and 1080p which is exactly the difference you are talking about. Interlaced vs whole frame. Not all TV's have scan lines. Any that are 1080p do not interlace.
- protomyth 14y ago
  You and the person voting me down seem to be missing the point of what I'm saying. A piece of film is illuminated and shown fully on the screen. There is no scan line. A TV is drawn one line at a time. There is a scan line. Interlaced vs Non-Interlaced has nothing to do with what I am talking about as both draw one line at a time. Interlaced just means it draws half the first tick and half the second tick. Non-interlaced draws the full frame each tick. Both draw a line at a time.
  - __david__ 14y ago
    No, NTSC on a CRT is drawn one line at a time (it is physically scanned by the electron gun). But TV is not NTSC any more and CRTs are dead/dying. Your HD flatscreen (plasma or LCD) does not draw one line at a time. HD is decoded into a framebuffer and that framebuffer is drawn on the screen in some hardware specific way. It may be rectangles, or the whole screen, or different vertical/horizontal slices (with very high refresh rates so you don't see flicker). Edit: Moveover, "film" is almost always digital nowadays (I don't think I've seen a non-digital projection in the last 5 years) which means that the picture gets to the screen via some form of LCD projection. So your home TV and film are basically the same at this point. You would've been right 10 years ago, though.
  - shardling 14y ago
    I accidentally downvoted your original post, but of course there's no way to reverse that. :( (Some of HN's design baffles me.)
  - ars 14y ago
    That's not true. A film projector has a moving shutter - only part of the image is visible on the screen at a time. You can prove it by using a camera with a fast shutter and trying various shutter speeds. If you have a leaf shutter in your camera you'll have to hold the camera in all 4 direction to test it properly - you don't want the projector shutter and the camera shutter to interact weirdly.