iMovie '09 and Garageband playback in milliseconds.

Discussion in 'Digital Video' started by boudi140, Oct 10, 2009.

  1. boudi140 macrumors newbie

    Mar 30, 2009
    Hey guys!
    I'm doing this physics project where it involves me filming dominos falling down and measuring the time taken.
    So I decided to try filming the procedure, locating the initial and final position of the dominoes and reading the time between them.
    But iMovie '09 only measures up to 30. Since in 1.x, I believe that x would be the number of the frame, and not in hundredths.
    What can I do to see my clip on a timeline including milliseconds? Help urgently needed.

    I am using photo booth to film the trials.

    Thanks in advance!
  2. huntercr macrumors 65816

    Jun 6, 2006
    Sorry, a regular SD NTSC video camera only films in 29.97 frames per second... so the minimum time segment you can have is 1/29.97*1000=33.36 milliseconds

    If you're using photobooth, does that mean you're using the isight built in camera of your mac? You may be getting a considerably lower framerate then. I would consider using a video camera in that case and capture within iMovie instead
  3. boudi140 thread starter macrumors newbie

    Mar 30, 2009
    Oh okay, so using iSight is out of the question. If I were to use a camcorder, would there be any other app that would put my video on a timeline instead of measuring by frames?
    By this, I mean that if I select any point on the line it gives me the corresponding second and millseconds (2 figures) instead of the frame within that one second.

    Just something I thought I'd add; Video doesn't really matter, I can easily measure by audio because the room is completely silent until the first domino is struck and the last domino falls down, so if there's any thing like that, that would be great.
  4. huntercr macrumors 65816

    Jun 6, 2006
    Sorry, I'm sure there's a program out there that might do this, but Quicktime, Final Cut and iMovie all measure subseconds as frames.
    You will get the most precision out of Final Cut, since you can easily move around at the frame level.

    If you have a HD camera you could film at 60i and get more precision there I believe.

    Now audio can capture at this speed of course.
    I'm guessing if you only need to measure this via audio, that you can find some sort of scientific audio measurement tool that will take it down to the millisecond level... video editors will never be able to give you that kind of precision simply because the source medium can't go that fast.

    Depending on your experiment, though, 33ms might be high enough precision though so maybe a video camera will work for you.

    Hope this helps!
  5. DaedalusYoung macrumors newbie

    Oct 10, 2009
    I don't know how it works in NTSC, but if you have a properly interlaced video, you have (about) 60 fields in one second, so the minimum would be 16.7 msec.

    Anyway, if there's any video editor out there that works with sub-frames, you wouldn't ever get more accuracy than that. If the audio is good enough to use as measurement, you can simply export the audio as aif from iMovie and import in GarageBand. There's a tiny clock-icon at the bottom in GarageBand next to the time indicator, you can click it to toggle between time down to milliseconds and bars & beats. So click it to get it to display seconds and milliseconds, drag the audio so the first falling domino is on time 00:00:000 and put your cursor at the sound of the last falling domino. You should now have a pretty accurate timing.

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