When viewing video clips in DV codec format in Quicktime 7 the quality is low by default. But here is a very simple solution for you to sort this out.
If in Cinema 4D and you have something close up to the camera it will be in focus and something in the distance is will be blurred, known as depth of field.
By default if you try and save a Final Cut file to and older version of Final Cut say V5 to V4.5. The older version will not be able to open it.