American sitcoms converted from analogue videotape (NTSC to PAL) have always been smudgy, yellowing affairs. Until the arrival of digital tape, that is - all episodes of Roseanne repeated on Channel 4 from 1998 now look like they’ve been re-converted from their original American source, and look much better for it. The quality of the picture is virtually identical to that of UK tape.

[NOTE: This is no longer an issue for modern American sitcoms like Friends and Frasier - here, the video picture is converted to resemble ‘film’, and the Americans seem to have the technology to do this without the picture looking like shit.]