4 Replies Latest reply on Sep 2, 2008 2:06 PM by Ann Bens

    Slow motion clips look very poor

      I have slowed down some of the clips in my project, burned them to disc and watched them back on the TV.

      The clips I slowed down look pretty bad.

      It is very jumpy and flickery at times and it even makes you feel sick and gives you a headache !

      I read about de-interlacing the clip because of the odd and even fields, so I did this expecting to see a huge improvement.

      But there was only a marginal improvement.

      I then remembered watching slow motion video via my DV Camera (Sony PC105) when it was connected to the TV. This was nice and smooth and was playing at half speed.

      How come the DV camera can play the video nice and smooth yet when I slow down a clip in PE4 its almost unbearable to watch ?

      Anyone suffering from epilepsy would probably have a seizure.

      I am not reducing the speed anymore than 50% (i.e. half speed), for some clips its even less than this.

      Is there anything else I can do ?
        • 1. Re: Slow motion clips look very poor
          Steve Grisetti Adobe Community Professional
          Remember that, when you slow your video, you're actually adding frames. So, if you start out with a video running 30 frames per second and you run it at 50% speed, you now have a video running at only 15 frames per second. And that can start to look jittery.

          You can minimize this effect by apply Frame Blend to your slow motion clips. You can get to Frame Blend by right-clicking on your clip on the timeline.

          All of this is assuming that this video is captured by Premiere Elements from a miniDV camcorder. Video captured from DVDs or from camcorders using the MPEG file format, and particularly video from still cameras, can pose additional problems, do to the way they store data for individual frames.
          • 2. Re: Slow motion clips look very poor
            Level 1
            I can understand how slowing the clip down reduces the frame rate.

            The footage was captured by PE4 from a miniDV camcorder (Sony PC105) via firewire.

            And the captured frame rate is 25 fps (PAL).

            So when I reduce the speed by 50% the frame rate reduces to 12.5 fps

            The thing I dont understand is that when I play video in slow motion from the camcorder and watch it on TV, the footage is nice and smooth.

            What does the camcorder do to make the footage nice and smooth that PE4 doesnt do ?

            I selected 'frame blend' but I didnt bother burning it to DVD to see how it looked on TV.

            'Frame blend' made the video look too blurry.
            • 3. Re: Slow motion clips look very poor
              the_wine_snob Level 9
              John,

              This is just a guess, as I do not know the specs of your camera, but I would say that it uses a mechanical slow-mo, i.e. it actually advances the tape more slowly. No frame work needed. An NLE cannot access the mechanicals of the computer, or DVD player to physically slow things down, so it has to do it with frame interpolation instead. This usually works to some degree, but is not without visual problems.

              I've seen some, who recommend only increasing/decreasing the speed to certain points. If more/less is needed, they do it in steps. Unfortunately, I have done neither slow/fast motion, of more than a tiny amount, so cannot direct you there.

              I hope that Steve, Paul or others will have more ideas for how best to accomplish this 50% change in FPS for you.

              Good luck,

              Hunt
              • 4. Re: Slow motion clips look very poor
                Ann Bens Adobe Community Professional & MVP
                Slow down your footage to 80% then make a dv-avi, put it back on the timeline and reduce it again to 80%. This will probably give you a better speed. You can also duplicate the slomo and put it above the original in the timeline and offset it 1 frame and lower the opacity to 50%. See what works best.