It seems like only yesterday that high-definition TVs were being touted as the ultimate in colour and clarity. And many believed it: more than 3m HD-ready televisions have been sold in Britain since 2004. But now an even newer standard, called full-HD, is being hawked that promises to deliver even better picture quality.

So what’s the difference? In straightforward terms, a full-HD screen consists of more lines of pixels than a standard HD-ready set, and the more lines that a screen contains the better the picture quality it can theoretically offer. Full-HD TVs have 1,920 vertical lines and 1,080 horizontal ones. However, it is the horizontal number that is commonly used for comparison and regular HD-ready sets have 768, while standard definition (SD) models have just 576 visible lines.

The set makers claim that this means full-HD models offer pictures with finer detail and more subtle colours. The reason is that most HD programmes, such as Sky’s pay-TV broadcasts, have 1,080 horizontal lines and HD-ready sets must perform some digital jiggery pokery to display these pictures. A full-HD set can show this HD footage without resizing the images.

Are these premium-priced screens worth the money? InGear examined six full-HD televisions and compared them not only with each other but also with the best HD-ready models. Apart from the huge Panasonic, all the models under review have LCD screens, because full-HD plasma sets are still rare.

Each was fed a variety of HD broadcasts as well as next-generation DVDs and games. We also assessed how good SD Freeview broadcasts and normal DVD movies looked. This was where the wheels came off for some of the full-HD sets. They all performed well with HD material, but only the Philips and the Sony were able also to make normal SD broadcasts look decent. This is because the inferior calibre of Freeview’s video must be artificially boosted when shown on these screens – much like blowing up a photo to the size of a poster.

The Sharp wasn’t bad at this tricky task either, but the other models under review all had a distinct drop in quality. The makers would argue that this is beside the point: these cutting-edge sets are pitched at early adopters who watch largely HD content such as pay-TV or next-generation DVD players. And all these sets did deliver enhanced performance when showcasing HD movies or TV shows. Yet despite the hefty price tags this was only modestly better than a good HD-ready model and only noticeable on screens larger than 42in.

Still determined to go down the full-HD route? There’s another complication to consider. Despite the better-than-normal resolution with 1,080 horizontal lines, some full-HD sets – such as the Philips and JVC – cannot handle the top standard of HD signal, which is known as 1080p and is currently used by the latest games consoles and next-generation DVD players. Most HD broadcasts use 1080i (see jargon buster, below).

So should you invest in a full-HD set? For movie buffs who watch mainly HD-grade material and have no shortage of money or living-room space it could be a sound idea, as long as the set is a good one overall. As with all technology full-HD highlights the folly of obsessing about one headline-grabbing specification – in this case, screen resolution – rather than hunting for a well-rounded product. It is like buying a car based solely on its top speed without considering roadhandling or fuel economy.

Furthermore, the clear implication of all this marketing mischief is that “HD-ready” televisions somehow aren’t really ready for HD movies or games, but this is not true. Owners of HD-ready sets can rest assured that they will enjoy excellent pictures that are genuinely HD quality.

In short, don’t feel compelled to splash out on one of these full-HD sets. Your HD-ready set will handle HD material almost as well and by the time you have bought a full-HD model the marketing men will probably be trying to sell you a “mega-HD” set.

HIGH-DEF HERO

Sony KDL-46X2000 – typically £3,300, or £2,550 from www.laskys.comStunning HD images and black tones for an LCD

This stylish 46in set sits at the top of Sony’s range. Its intuitive menus boasted a wide variety of easy-to-use features but it was the picture quality that really impressed us. An HD viewing of Star Wars Episode III delivered one of the sharpest pictures ever seen on test. In fact its clarity revealed previously invisible details on the film’s spacecraft. Unlike many LCD screens, it had no problems when it came to reproducing even the inkiest of blacks, and it handled nonHD Freeview material extremely well. There are plenty of sockets for plugging in additional HD kit and it is the ideal partner for the full-HD PlayStation 3 console. So, while the price of this set is sky high, the force is strong with this one.

SUPERSIZED SUPERSTAR

Panasonic TH-65PX600 – typically £6,500, or £6,100 from www.letsgodigital.co.ukGreat showcase for full-HD but at a cost

The TH-65PX600 really does have a 65in screen – so huge that the target audience is limited. But this monster is one of only three full-HD plasma screens currently on sale in Britain. Its size highlights the benefits of full-HD, such as subtle colour gradations and greater clarity. Facial flesh tones lacked the waxiness common to many lower-resolution sets, and a close-up of Gollum’s face in The Return of the King was unnervingly realistic. The Panasonic has a built-in Freeview tuner, programmes viewed on which looked markedly rougher than the HD broadcasts. This giant set is a treat for serious home-cinema buffs who can’t wait for Panasonic’s forthcoming 50in full-HD plasma set.

SUAVE GADGET-FEST

Philips 37PF9731D – typically £1,900, or £1,480 from www.rankhour.comTop performer despite a glaring oversight and modest size

Philips has long argued that HD-ready televisions have sufficient screen resolution, but it has still jumped on the bandwagon with this full-HD set. Like most Philips TVs, the suave-looking 37in 37PF9731D is laden with gadgets such as Ambilight – pools of coloured light emitted from the rear of the set to enhance atmosphere and reduce eyestrain. However, despite its many connections, this model is incapable of handling a top-calibre 1080p HD signal – a glaring omission at the price. Nevertheless, this pin-sharp 37in LCD really swung into life with HD movies, Spider-Man’s suit shining intensely even in the darkness. Better still, Philips’s clever Pixel Plus 3 technology eked the best from Freeview, losing nothing to an HD-ready set.

VALUE-PACKED BEAST

Sharp LC-37XD1E – typically £1,250, or £899 from www.martindawes.net Competent, well priced and no monkey business

This decent 37in model offers a bunch of fancy features. What matters, though, is performance and the Sharp showed off HD movies well. It delivered excellent detail in longer-distance shots of New York on the HD-DVD of King Kong and created the rich, bright colours expected of a full-HD set. Better still, it displayed blacks properly in dark scenes, which is a common failing of LCDs. The Sharp coped reasonably with Freeview images, but struggled with fast-moving video such as football, and the relatively modest screen size also means you may not notice the benefits of full-HD. It proved tricky to set up and has a clumsily laid out remote control. But for well under a grand, it’s a bargain.

FLAWED CONTENDER

JVC LT-46DZ7BJ – typically £3,000, or £1,503 from www.digitaldirect.co.ukGood sound and vivid HD images but saddled by flaws

JVC’s debut full-HD model has an appealing retrograde styling that conceals up-to-the-minute technology. However, one significant problem with this set was that some of its fancier picture-processing features, which are aimed at enhancing the image, instead made them appreciably worse. Also, neither of the JVC’s two HDMI inputs would accept the highest resolution of HD signal – 1080p. This 46in set delivered some aspects of the full-HD experience well, the lush backgrounds in Dances with Wolves looked great, for example. However, it struggled in other areas, with washed-out darker colours and blurring on fast-motion footage such as horseracing. The JVC’s performance with the integrated Freeview receiver was also uninspiring.

FASHION STATEMENT

Samsung LE40F71 – typically £1,300, or £1,000 from www.pcworld.co.ukCute-looking set despite the overly bright colours

This elegant Samsung offered credible full-HD performance, delivering particularly intense colours that helped create a far more dramatic picture in Kill Bill Vol 1 than was expected of a 40in screen. But some curious colour tones consistently crept in; for instance Jack Bauer’s face kept going red in the outdoor scenes of the show 24 – which is broadcast in HD – and this wasn’t because of his anxiety. The set also had slightly weak audio and, bizarrely, lacks a built-in Freeview tuner. The Samsung has an alluring piano-black finish and represents decent value for a full-HD set, especially for those who like vivid pictures, but it is hard to recommend wholeheartedly.

JARGON BUSTER

1080p Highest calibre of video signal. Contains 1,080 horizontal lines that are progressively scanned (hence the “p”) to create a more solid image. Most HD broadcasts are in 1080i (the “i” stands for interlaced, a slightly inferior video signal)

Full HD A variant of HD-ready TV with a higher than usual screen resolution of 1,920 x 1,080 pixels

High definition (HD) Television technology offering clearer and more detailed pictures, in contrast to standard definition (SD)

HDMI Digital connector that transfers video and surround audio to a screen in one convenient cable. Look for at least two HDMI sockets on a TV set

HD-ready European standard for sets able to display HD material. Screens have at least 720 horizontal lines and a digital video input designed to prevent piracy

Resolution Number of pixels (points of light) on a screen, expressed as lines vertically and horizontally. In theory, more means better images

Research supplied by Home Cinema Choice magazine Reviews adapted by John Archer All prices include Vat and delivery

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