Opening Moves Page 4

Ironically, considering the advanced technology in play here, you cannot create as sophisticated an edited work even with the Pioneer or Panasonic deck as you can with a couple of editing-friendly VCRs and an editing controller, let alone a full-blown computer-based editing system. In addition, each edit you make may be accompanied by a freeze frame and a slight delay as the recorder recues the disc, and the edit points may shift slightly from where you put them.

Video Fine Points Here's where video Grand Masters are separated from the pack, since the real-time MPEG-2 video encoding performed by DVD recorders is probably the most mathematically complex operation you'll find in any piece of consumer-electronics gear.

You might have noticed that I didn't list superior video quality as a general advantage of recordable DVDs over VCRs. That's because the results you get depend not only on the recorder but on how it's used. As you increase maximum recording time by switching through each recorder's various "modes" (1-hour, 2-hour, and so on), you eventually decrease resolution to approximately VHS quality (see "In the Lab") while increasing MPEG encoding artifacts, which further diminish picture quality. MPEG artifacts appear very different from VCR signal noise, and in the longer recording modes (3 to 4 hours and up) they look worse to me than the tape noise you get with VHS running at LP and EP speeds.

For example, one of the most noticeable MPEG artifacts is "macroblocking," in which you can see the blocklike chunks into which the picture is divided for processing. Macroblocking is a static phenomenon - the blocks don't move from frame to frame, which can make them more noticeable than tape noise, which is random from frame to frame and appears as increased graininess. The upshot: if you care about video quality, you probably shouldn't use recording modes longer than 2 hours with any of these decks.

But even using each recorder's (top) 1-hour mode, don't expect to get image quality equaling that of a well-mastered commercial DVD. A sharp-eyed viewer with lots of experience in looking for MPEG-encoding artifacts wouldn't have trouble spotting the difference between a recordable-DVD copy of a broadcast or camcorder footage and a standard DVD. Nonetheless, the Panasonic and Pioneer recorders made recordings in their 1-hour modes that came very close to being indistinguishable from our 30-minute master MiniDV-format test recording (see "Seeing Their True Stripes," right). The recording made on the Philips in its 1-hour mode was not quite as good. In particular, macroblocking was sometimes visible, and the picture had a graininess that was not apparent in the master or in the other two dubs. In the longer recording modes (3 and 4 hours), the performance gap narrowed, but the Philips still lagged behind the Panasonic and Pioneer decks in these respects.


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