HAVING seen interest in 3D television fizzle, electronics firms are eager to find another blockbuster product that will get consumers to splash out. The development most are hoping will do the trick is a display technology known as Ultra High-Definition, which offers four times the resolution of today’s most advanced “1080p” HDTV sets. No question, Ultra HD provides stunning images—at least when displaying content created in the new “4K” video format. Unfortunately, only a handful of feature films (including “The Amazing Spider-Man”, “Prometheus” and “The Hobbit”) have been shot with 4K-capable cameras.
Will 4K follow 3D’s fate? It is far too early to say. But 4K television—far more than 4K cinema—faces some formidable obstacles. As with 3D television, the new 4K television format takes its lead from Hollywood. The existing wide-screen digital format used in cinemas is 1,998 pixels wide and 1,080 pixels tall. The 4K film standard has twice the resolution vertically and twice horizontally—ie, 3,996 pixels across the frame and 2,160 down—making it four times sharper all round.
By contrast, the 4K format used in television is slightly narrower, having 3,840 pixels across and 2,160 pixels down. The screen width was reduced to maintain the 16:9 aspect ratio of HDTV, with its 1,920-by-1,080 pixel count. This makes it possible to show existing video content that has been “upscaled” for Ultra HD without the need for black “letterbox” bands above and below the picture.
But who actually needs a super-sharp 4K television? 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. A study done some years ago found the median eye-to-screen distance in American homes to be nine feet (2.7 metres). But researchers reckon that, given the human eye’s limited acuity, people even with 20/20 vision should sit no farther than 1.8 times the width of the screen away from it, if they are to distinguish the detail displayed.