Apply simple math (if it disinterests you I understand, but I think you'll be greatly missing out) to the previous posting: 10.2ft/21frames = .48ft per frame x 18.3 frames(1sec) = 8.78ft per sec/1.47(1mph) = 5.98mph Parameters being (+/-) .3frame, because of full frame(18fps) vs partial frame (18.3fps) count