Sony will no longer use the standard DVD format in its video recorders, instead moving to Blu-ray Disc for all future models in Japan. The announcement was made at the same time as Sony, the biggest backer of the technology, unveiled four new Blu-ray Disc video recorders. They include support for dual-layer discs -- something that was missing from models announced this time last year -- and can transcode video into the more efficient MPEG4 AVC format to increase recording time per disc. A 50G-byte Blu-ray Disc typically holds just over 4 hours of HDTV when the over-the-air MPEG2 stream is recorded directly to the disc. By transcoding this stream to MPEG4 AVC it's possible to squeeze 16 hours of HDTV onto the same disc.

- The BDZ-X90 is targeted at home cinema use and is capable of 1080p video output -- the highest quality of several video subsets that fall under the HDTV banner -- and "Deep Color" output. This latter feature should mean better colors when using a TV with support for the HDMI1.3 signal. The machine has a 500G-byte hard-disk drive.

- The BDZ-L70 is focused on those with high-def camcorders and supports one-touch transfer of video from Sony Handycam camcorders. It has a lower capacity 250G-byte hard-disk drive.

- Finally there are the BDZ-T50 and T70 machines aimed at people who want to record digital TV without other bells and whistles. The machines have 320G-byte and 250G-byte hard-disk drives respectively.

Other functions on all four machines include 4X Blu-ray Disc recording for fast transfer of TV shows from the hard-disk drive to disc, lossless HDMI audio output, compatibility with the AVCHD format used on many high-definition camcorders and Sony's Bravia Link and Bravia Premium Photo technologies.