• jetA
    link
    fedilink
    English
    arrow-up
    16
    ·
    3 months ago

    That rolling shutter

    • 9point6@lemmy.world
      link
      fedilink
      arrow-up
      17
      ·
      3 months ago

      I was just thinking, do they not have high speed global shutter cameras for this purpose?

      Seems like the Olympic athletics would be one of the obvious applications of that kind of camera

      • oktoberpaard@feddit.nl
        link
        fedilink
        arrow-up
        15
        ·
        edit-2
        3 months ago

        It’s by design. They photograph only one slice repeatedly at the finish and then paste them all together. That means that everything you see here was at the same location, not at the same moment in time.

        • Ech@lemm.ee
          link
          fedilink
          English
          arrow-up
          6
          ·
          3 months ago

          So, to clarify - the x-axis is time, not space? That’s pretty cool.

          • oktoberpaard@feddit.nl
            link
            fedilink
            arrow-up
            7
            ·
            3 months ago

            Exactly, so on this photo you can see exactly who finished at what position, because it’s all taken at the finish line.

        • Rolando@lemmy.world
          link
          fedilink
          arrow-up
          4
          ·
          3 months ago

          everything you see here was at the same location, not at the same moment in time.

          Wouldn’t that mean that it shows everyone crossing the finish line at the same time? Since they were all at that location eventually.

          (I’ve read the wikipedia page and the rest of the comments here, but I still don’t get what’s going on.)

          • oktoberpaard@feddit.nl
            link
            fedilink
            arrow-up
            11
            ·
            3 months ago

            Imagine a camera with only one column of pixels, so a resolution of 1x3000, for example. You point it in a fixed direction and you keep firing extremely fast. Eventually you’ve photographed everything that has passed the camera. Paste the pixels together from right to left, and you’ve got something resembling a normal photograph, but with some distortions due to the time difference between the photos. For example, if someone put their foot on the ground in front of the camera, it will be stationary between photos and appear smeared out in the final result. Since every column of pictures is made at the exact same location, you can determine that the person on the right has finished first and the person on the left last. They apparently measure this at the level of the torso (the red lines).

            • Rolando@lemmy.world
              link
              fedilink
              arrow-up
              2
              ·
              3 months ago

              Imagine a camera with only one column of pixels, so a resolution of 1x3000, for example. …

              Paste the pixels together from right to left …

              … They apparently measure this at the level of the torso (the red lines).

              Oooh, these were the facts that I was getting hung up on. Thanks for the explanation!

            • Ghoelian@lemmy.dbzer0.com
              link
              fedilink
              arrow-up
              1
              ·
              3 months ago

              Ahh so if I understand correctly, the track and the ads behind them are actually the same part of the track, instead of the area actually behind them?

              • oktoberpaard@feddit.nl
                link
                fedilink
                arrow-up
                1
                ·
                edit-2
                3 months ago

                The red lines on the finish line are real and the ads are projected from a small vertical projector at the other side of the track and are not visible in real life.

        • jetA
          link
          fedilink
          English
          arrow-up
          3
          ·
          3 months ago

          That seems to contradict the banner on the top of the photo that is clearly a large horizontal banner seen from a wide field of view

            • jetA
              link
              fedilink
              English
              arrow-up
              7
              arrow-down
              1
              ·
              3 months ago

              A mixed reality photo finish is going to be confusing for the viewer when they try to make sense of this distorted photo.

                • jetA
                  link
                  fedilink
                  English
                  arrow-up
                  2
                  ·
                  edit-2
                  3 months ago

                  Yeah! I read it, but I thought it couldn’t be related because the example photo in wikipedia demonstrates a very specific background effect. So I was confused :)

                  Also, who do the wildly varying shadows work in the silt photo effect? That means there are very different light sources at very different angles on the runners