Rear projection technology is enjoying something of a renaissance. Once a cheap, rather unimpressive big screen alternative to the likes of plasma and LCD, it has now blossomed into a genuine option for those seeking the best quality pictures.

This is almost solely due to the widespread adoption of DLP projection technology, which remedies most of rear projection's major problems (namely the bulkiness and the crap picture quality) at a stroke.

Another big development that is set to increase rear projection in our affections is manufacturers' swift moves to ensure that they have HDTV compatibility. Thomson's latest large screen effort is a perfect example of this.

Its DVI connection is not merely for hooking up a PC (although it can be used for that if you wish): because it is HDCP compliant you will be able to use it to input all-digital HDTV video from Sky's forthcoming set-top box and it means it's safely future proofed. It's also compatible with DVI and HDMI-equipped DVD players.

Dark matter

A screen this big lives and dies on its picture quality, and thankfully Thomson has done a reasonable job of not messing this aspect up. One of DLP's strengths is its ability to create convincing areas of dark shadow, and this is reflected here.

Colour reproduction is slightly patchy, with yellow areas appearing oddly garish at times. We managed to tone this down by adjusting the colour settings, but never managed to make it look totally perfect.

Thomson's own Hi-Pix image processing makes an appearance too. This is designed to increase detail while reducing flickering, and it works well with most video sources (including the built-in analogue TV tuner).

It cannot be turned off, however, and there are times when this would have been a handy option. For example, when we hooked up a DVI-outputting Denon DVD player, Hi-Pix worked in combination with the player's own image upscaling technology, resulting in a picture that was far too detailed for its own good:

speckles of picture noise were enhanced to make them more visible, which isn't a good thing when displayed on a screen as big as this. Because you can't turn off Hi-Pix, you have to turn off the upscaling on the DVD player to lessen this effect; in our opinion, it would have been preferable to have the choice.

End of the rainbow

DLP projectors often exhibit a couple of annoying side effects, but we're happy to report that the Thomson doesn't suffer greatly from either. The rainbow effect is noticeable every now and then in brighter areas of the picture, particularly when you're watching the TV in a darkened room, but it's so minor that it's rarely off-putting. Motion artefacts, meanwhile (those annoying sparkly apparitions around rapidly moving on-screen objects) were non-existent.

The Thomson also delivers nicely in the sound department. The built-in speakers comfortably supply decent quality stereo sound, and as a bonus you also get the options of both Virtual Dolby Surround Pro Logic II and SRS TruSurround XT modes (bit of a mouthful, that)

Rear projection tellies have a reputation for being massive, and this one isn't going to do anything to change that opinion. Then again, it is a 50-inch model, so anyone expecting something suitable for the bedroom is either, a) fooling themselves, or b) in possession of a really big bedroom. That said, with a depth of only 174mm, it's actually possible to stick this baby up on your wall.

Fight the flab

With beauty being in the eye of the beholder, we don't want to comment too much on the TV's styling; you can see for yourself what it looks like from our picture, and in our experience style is a very personal thing.

What we will say is that the large, pale-coloured expanse underneath the TV looks a bit odd, so even though there is the option to wall-mount the whole thing, we believe this bizarre extra flab will put most people off doing so. The build quality, meanwhile, could be a touch more sturdy: this set appears to contain marginally more plastic than Pamela Anderson.

Connectivity, on the other hand, is verging on the superb. There's the DVI input that we've already mentioned, and three Scart sockets to accommodate your existing audiovisual kit. You also get the usual S-Video and composite video connections.

The one thing missing on the video input front is a component connection, but we can't criticise Thomson too highly for this omission, as the DVI socket is going to be getting far more use in the near future.

As you'd expect from a £3,000 television, there is a generous ladling of extra features spooned in to make this purchase worth your while: a selection of different picture-inpicture modes, Teletext, NextView and so on. A universal remote control is bundled (able to control up to six different items) although as with all Thomson remotes, it's irritating to use at times and features a button layout that would puzzle a pilot.

We've got some mixed feelings about the 50DSZ644. On the plus side, it's a future-proof RP screen that combines reasonable picture quality with decent design. On the minus side, however, it's not particularly cheap, and it has one or two annoying quirks. We like it, but it isn't as good as the cheaper Sagem HD-D45.