encoding DV video (and others) from ffmpeg
ffmpeg -i /Users/jcburns/Movies/blurry\ motion\ thingie.mov -vf scale=720x480,setdar=4/3 -pix_fmt yuv411p -c:v dvvideo testblurry.mov
input comes first, then vf scale thing, including the dar, the display aspect ratio
you have to tell it -pix_fmt yuv411p because DV coming in as 422 (as it would in ProRes) will by default be encoded as DVCPRO50.
[dvvideo @ 0x7fd0ef026e00] Frame size: 720x480; pixel format: yuv411p, framerate: 30000/1001