"At a distance of nine feet, even an existing HDTV set would need to have a screen of around 70 inches across the diagonal for viewers to benefit from the resolution they have paid for.
The Economist has gone to some lengths to explain to its readers several aspects of Ultra HD, and in turns explained that there is next-to-no content, no practical delivery method forthcoming, and that "most people sit too far from the screen to be able to see the detail it (HD content) offers." Only after describing the associated challenges in insurmountable terms does the article conclude by saying that delivery obstacles will be overcome and that Ultra HD will eventually become mainstream.
While trouncing Ultra HD, several statements about HD are mixed in, including, "The resolution of even an HDTV set with 1,080 progressively scanned lines (ie, continuously from top to bottom) is wasted on the vast majority of viewers. Most people sit too far from the screen to be able to see the detail it offers... At a distance of nine feet, even an existing HDTV set would need to have a screen of around 70 inches across the diagonal for viewers to benefit from the resolution they have paid for. With anything smaller at that distance, details simply blur into one another... Today’s HDTV sets begin to look spotty when their meagre 2.1m pixels are spread over screens greater than around 80 inches."
The article also cites 2010 as the year that HD went mainstream before declaring that "it is likely to be 2025 before Ultra HD is in half of all American homes." Nevertheless, the presumption that is carried through the article is that the majority of viewers sit nine feet away from their TVs and at that distance cannot notice the detail provided by HD over SD. That presumption carries with it a negative connotation for the current state of HD, which tends to undercut any commentary with regard to the future of Ultra HD.
Source: The Economist