>>86486728>>86486772To elaborate on this unhelpful dickhead's reply, live action film has:
* motion blur
* fully rendered texture
* fully rendered light and shade
* lens effects
* other subtle live-action film effects
When you rotoscope, you lose all that, and the result is rather jerky and stilted unless you polish it a lot. The most obvious example: line boil. Live action footage has no outlines, so no line boil. If you rotoscope, suddenly the outlines are wiggling like crazy unless you take steps to prevent it. Such steps include lowering the framerate (animating on 3s, 4s, etc) or, the best solution, redrawing the frames instead of tracing them, which is what they did at Disney.
