4K on 1080 screen. Prime vs iTunes.

[Drooch]

When I stream Amazon Prime 4K UHD movies from my Apple TV to my 1080p plasma it looks AMAZING, I can do direct comparisons of, for example, Ghostbusters II in HD and UHD and the difference is drastic. Clearly it’s downconverting the UHD for my screen, much like my 4K player does.

However, when I play 4K movies bought on iTunes it just plays the old 1080p version, which looks meh. Does anyone know why this is, or if there’s a workaround to get the superior 4K version squeezed down?

Also, if I were to get 4K Netflix, would it stream downconverted 4K UHD versions, or just the inferior HD versions?

Thanks in advance.