there is problem to use iMovie on ‘El capitan’
screen ratio is wrong, top and bottom is trimmed, and it’s stretch vertically.
but, on Quicktime player, it works well.
there’s no problem on ‘Yosemite’.
now, it doesn’t work well on ‘El capitan’
the movie clip was recorded by panasonic GH1, 1080p, 24fps,
here’s the link for sample file
https://drive.google.com/file/d/0Bz_tTZMVTobUQ0dnOFJxRm5IQm8/view