The HDR-UX1 is one half of a dynamic duo of camcorders that Sony hopes will showcase the potential of both high-definition video in general and, more specifically, the AVCHD (Advanced Video Codec High Definition) format.

AVCHD is being touted by several manufacturers, including Sony and Panasonic as a more efficient and effective recording technology than MPEG2, as it uses the increasingly popular MPEG4 (H.264 codec) compression in order to record its high- definition images.

The UX1's other half is the Sony HDR-SR1. What marks the difference between the two cams, however, is the choice of recording medium. The SR1 uses a 30GB hard drive to store video, while our UX1 can capture its movies to a variety of 8cm DVD media, including the higher capacity Dual Layer discs.

This offers consumers an intriguing choice. A 30GB hard-disk drive provides between four and 20 hours of video storage, but it's all on one hard disk - and you'll have to hook up the camcorder to a computer or other device to transfer your footage. Using DVDs there is less space on a disc, meaning an investment in blank media, but it does enables you to build a library of discs and your standard-definition discs can be prepared in the camcorder for playback in a computer drive or home DVD player.

You notice we don't say high-def discs; because it's here we unearth a thorny issue about HD and AVCHD in particular. Currently the problem for consumers is that if they choose this cam, record in HD onto DVD, and finalise discs for playback in other devices, then those 'other devices' are going to be in short supply. The reason? Well to play back AVCHD discs you'll need a compatible, hard-to-find player.

It's a significant drawback for the UX1 - as to enjoy HD footage you'll have to connect via HDMI and watch the footage direct from the cam on an HD-Ready TV, or import footage to a PC, use the basic supplied software to edit, and create a full-size DVD - negating the need to record on AVCHD discs in the first place!

The UX1 features exactly the same design as the SR1, the only notable difference being the housing for the 8cm discs, which here is on the right flank of the machine. It's a sensible layout and one that makes for stable shooting, easy access to controls and a nice recording experience.

Users can choose to record on several types of DVD media: DVD-R, -RW, RW and DVD R DL. The DVD-RW and RW discs need to be used if you want to create playlists from your footage, while these discs can also be 'unfinalised', allowing you to add footage to a disc you had previously 'completed'.

The UX1, like its colleague the SR , can record both high definition (HD) and standard definition (SD) footage but, depending on the disc you are using, you might have to choose the mode in advance. If you're using DVD-RW and DVD RW discs you'll be asked to format them before you can begin recording. You'll also have to decide if you want to record high- definition or standard-definition images on them. Once you've made your choice you can't change midway through recording.

The camcorder has four HD recording modes (HQ , HQ, SP and LP) offering variable bitrates from a maximum of 12Mbps to 5Mbps and recording times vary from 15 minutes (best quality) to 32 minutes (LP mode).