These quality comparisons are not really fair to the original films or even the special editions. The OT and SE screen shots are undoubtedly sourced from bootlegs, while the 2004 screen grabs are coming from official DVDs. Now I have no doubt that the official DVDs will be unparalleled in terms of picture quality, but the bootlegs DVDs (or laserdiscs and VHS tapes for that matter) really don't look as bad as those screen shots would indicate.