Professorhat (or anyone!) - the HD ready Pioneer 427xd that I've got will accept a 1080P signal only at 24fps. Bizarre I know, but true. Obviously every other type of signal (480i/p, 576i/p, 720p, 1080i) will work at 50 or 60 hz as you'd expect. Hopefully my original question makes more sense now. I realise that I should have explained this properly in the first place!