4K in the UK? It could happen sooner rather than later, if viewers give a thumbs up to feedback tests currently being conducted by a British broadcaster. According to a senior figure at a company that is directly involved in the experiments, people are being asked if they can spot the difference between 4K and regular 1920 x 1080, which will help to decide whether the format is worthy of immediate investment. Our source refused to reveal which broadcaster is running the show, beyond saying that it has complete control over its pipeline right down to the set-top box, which hints at Sky or perhaps Virgin being likely candidates. When asked how 4K TV might be transmitted as a mainstream service, given that it contains four times the resolution of Full HD, he simply replied that the broadcaster would "compress the hell out of it," which surely only cements his credibility. Next stop, 8K.