Never heard of it, right? Yeah, most people in the video field get an inquisitive look on their faces when I mention the topic!
The Digital VHS standard has actually been around since 1995, developed by a coalition of manufacturers. What it does is allow you to record and playback stream HDTV broadcasts.
If you'll remember in our Digital Video Special of 2001 we had a chart of relative resolution (measured by how many lines drawn from top to bottom you can put across a screen before they become a gray blur), with regular VHS being 240 horizontal lines, broadcast television being 330 lines, S-VHS/Hi-8 being 400 lines, DVD players being 480 lines (twice the sharpness of VHS tape), DV Mini and Sony Digital 8 being 480 to 540 lines and the best high quality (HQ) digital televisions being upwards to 600 lines. Well the most expensive HDTV sets with 6 million dots making up a 16:9 ratio matrix of 1920 x 1080 pixels in progressive scan mode is capable of delivering over 1,000 line of horizontal resolution. That's twice the sharpness of DVD or DV Mini!
Since most people don't have HDTV yet they aren't really noticing, but once they see a neighbor's who has the same HDTV wide screen set but gets a much clearer picture on their rental movies because they use D-VHS and you are still using the low quality DVD format! At least, that's the theory behind this!
D-VHS is also expected to keep the long standing analog VHS format alive and well, since the units are designed to be able to play and record regular VHS and the higher quality S-VHS on the current, low cost tapes you find everywhere. D-VHS broadcasts, however, must be recorded on special D-VHS tapes and you can get up to about 5 or 6 hours of recording time at full matrix (1920 x 1080) per extra length tape. You can also record at lower resolutions (down to DVD quality which is 700 x 400) and get extended time -- up to 30+ hours on the same tape (approx $16 to $20 retail for the standard tape)!
There are also a variety of pre-recorded movies you can buy in the D-VHS format, but unlike the DVD offerings there are no menus, no special footage, no foreign versions and not every D-VHS player may handle the special D-VHS "Theater" tapes -- which is something you should inquire about if you are planning to buy one of these gems and they will cost you almost what the HDTV set ran in price! Currently D-VHS units sell for around $2,000.
With more and more TV shows simulcast in HDTV (which is a high quality digital stream that can only be picked up by an HDTV tuner -- the D-VHS unit records this raw data, much like a hard drive records you DV Mini signals through a digital capture card) and the price of HDTV dropping all the time, by 2005 we can expect to possibly see a lot of these in use and priced far more economically!
For now, it's probably going to take a lot of searching just to find one demo unit close to you! D-VHS is not yet ready to be stocked in truck loads by Circuit City! If you're lucky, you find one model (sitting along side the Sony three chip camcorder that also sells for over $2,000).
Warning! There are also new DVD standards on the horizon, but it's hard to say if these will support double the pixels as currently some movies have to be on two DVD disks. If they doubled the quality every movie would need two, three or even four DVD disks and no one wants that!