[Si-Co]

That Channel 4 closedown is bizarre, was the black and white, the silence and the not seeming to realise he was on air intentional?

I don’t think so. You can hear him being cued. These closedowns were filmed in the Preview 4 studio, I believe, and there were no monitors to refer to, probably just a locked-in position camera, so the announcer had no idea what was actually going out. The silent slide and clock with bizarre graphics were probably also unintentional, as was the lack of colour.