Over the holidays, I was at my parent’s place and watched some TV.
They’ve got a relatively new one, with the content coming over DVB-T.
At the time, I thought the picture looked strange, unnaturally crisp. But I couldn’t really put it in words.
Then, I stumbled on this comment on slashdot:

A lot of hi-def production looks terrible now-a-days because it’s too real, it looks like actors standing on a set

Bingo, that’s the metaphor I was looking for!