People are often surprised when I tell them Standard Definition (SD) Video can look gorgeous in their Home Theater.  The sad truth, alas, is that MOST people have never ever seen SD Video "done right"!  The problem is, at these resolutions (and data rates), there is NO margin for error.  ANY mistake in the content creation or video processing -- any corner cut in the setup at any stage -- WILL produce image defects that viewers can not ignore.  And such defects, once introduced, can NOT be corrected by any sort of subsequent image enhancement processing.  The critical information has been permanently lost.  At best you can blur such defects to make them less annoying.

This post discusses the technical details of image "Aspect Ratio", as found on traditional, SD-DVD movie discs, with tips for avoiding some common mistakes which will reduce your SD viewing quality.