The Other DTV

Maybe you already know this?but a lot of folks getting their first exposure to new video display technologies at Best Buy don?t?digital television and HDTV are not the same thing. The great unwashed who make that assumption probably also see DTV as some kind of technocratic plot to part them from their hard-earned dollars for something only golden-eyed elitists could appreciate. (Am I being needlessly polemical? Feel free to post and skewer me back.)

This misassumption makes the subject of SDTV, or standard-definition television, all the harder to approach. After all, as a home theater technology critic, I spend a large proportion of my time trying to convince the public that HDTV, or high-definition television, is worth the investment. But I also have a conflicting urge to defend the underdog. OK, so SDTV doesn?t provide as much resolution (defined as sharpness and detail) as HDTV. But it?s still a form of DTV, and therefore not to be underestimated.

The fact is, SDTV is already massively successful. Do you have a DVD player? Of course you do. So does every member of my family (I?ve made sure of that during the past few holiday seasons!) The DVD-Video format, to use its full name (I can be pedantic as well as polemical) is only one example of SDTV padding into our lives on silent cat feet. Two dueling high-def-capable DVD formats will be upon us by the year?s end, but standard-definition DVD will remain the standard, so to speak, until one of them emerges victorious, and that may take a while.

Has your cable operator talked you into buying one of those DTV packages with ?hundreds of channels??  Odds are good that the vast majority of those channels are DTV all right?but SDTV, not HDTV. In over-the-air TV, most analog channels have been duplicated by HD-capable digital ones, but even they carry SD signals much of the time.

Most satellite channels are also standard-definition, and while the launch of new transponders will increase the proportion of high-def channels, SD will continue to dominate. The one high-def-only satellite service, Voom, has been a conspicuous failure with just 46,000 subscribers?though I wish HBO and Cablevision founder Chuck Dolan well in his attempt to ensure Voom?s survival.

What is SDTV? For starters, it?s a necessary euphemism. To the founding fathers of DTV, looking to name a lower-resolution format, ?standard definition? sounded more appetizing than ?low definition? or ?sour-milk definition.?

Nonetheless, SDTV is very much a part of the ATSC?s official DTV specs. It?s a format with 480 vertical pixels, and 640-704 horizontal pixels (the latter for widescreen.)  It can use either interlaced scanning, which delivers each frame as a pair of gap-toothed fields, or progressive scanning, which delivers computer-monitor-like full frames.

Actually, under the definition commonly accepted by the Consumer Electronics Association, and therefore most DTV makers, SDTV uses interlaced scanning, while EDTV (enhanced-definition television) uses progressive scanning. Using that parlance, progressive-scan DVD (480p) is an EDTV signal source, while regular interlaced DVD (480i) is SDTV.

HDTV, simply put, delivers more pixels. The 1080i format (used by tube-based rear-projectors as well as CBS and NBC) provides 1080 by 1920 pixels with interlaced scanning, while 720p (a player in LCD and plasma displays?and at Fox and ABC) provides 720 by 1280 with progressive scanning.

Why wouldn?t you want more pixels, more sharpness, more detail? In the best of all possible worlds, HDTV would always be there for you, but back here in the real world, a lot of programming?newscasts, for instance?are still produced in SDTV.

Trust me; you don?t want to see what a senior anchorman?s complexion really looks like under a merciless high-def microscope. If station managers could hire only perfect-skinned teenagers as newscasters, your evening news program would sound like college radio, duuuude. They?d have to junk all the sets, too.

The lightweight cameras and expensive production trucks that take you to hurricane-prone areas and murder scenes are usually standard-definition. More and more sporting events, especially high-profile ones, are produced in HD, but they?re often hybrids?the long shot of the field may be HD, but the instant replay is more likely SD.

Bandwidth isn?t as much of a problem as you?d think, at least over the air. HDTV and SDTV programming both roam the airwaves in 6MHz channels, data-reduced as needed through the magic of MPEG-2 algorithms. That should give HDTV a painless migration path as the amount of actual HD programming production continues to grow.

But there?s a lot you can do with a 6MHz channel. What the broadcasters would like to do is something called multicasting?the jamming of several SD programs into a single channel slot with extreme prejudice (I mean compression). That?s already beginning to happen over the airwaves.

Don?t expect all that additional programming to appear in your cable system. The Federal Communications Commission just voted to make multicasting voluntary, not compulsory, in cable systems. Legally, the cable operators are required to carry only the ?primary video? stream of each broadcaster. They?d rather use whatever bandwidth they?ve got left over for potentially lucrative services, like video on demand.

The FCC?s 4-1 vote has been widely viewed as a victory for cable operators and a setback for broadcasters. However, the cable companies have struck a multicasting deal with public television, so you may get a little new SD-multicast fare after all.

SDTV?s?and EDTV?s?other significant gig is lower-end flat-panel display technology. The next time you see an amazing deal on a 42-inch plasma, or a less than 30-inch LCD set, read the fine print. Does that hot panel good have a native resolution of at least 720 by 1280 pixels? It might, but then again, it might not. There are your old buddies, standard and enhanced, staring you in the face again. I don?t recommend them for displays of 30 inches and higher. HDTV, even if it costs more, is the better buy in big screens, both for future-proofing and for long-term satisfaction.

But what about small sets? Hey, there are situations where SDTV is better than no DTV at all. Here?s a press-release headline from Thomson: ?RCA Targets Broader Consumer Base with 35 New Models at Affordable Prices for 2005.? In this context, the words ?broader consumer base? can be translated as ?you?d have to be an incredible doofus to buy an analog set when digital ones cost so little.? Alongside the company?s highly desirable HD-capable DLP-RPTV models and LCD flat panels are seven bargain-priced direct-view SDTVs, including two 32-inchers for less than $400 and five 27-inchers below $300. There?s your new bedroom set!

Look, if you can afford an HDTV, I think you should buy one, especially if your heart is set on a big screen. Better HDTVs do a fine job of scaling up and smoothing out SD and analog signals?and you?ll get an amazing picture on whatever channels and programs have a true HD signal (and good production values.)  By 2006 or 2007 at the latest, that will include at least some of the next-generation HD DVDs and Blu-ray discs that you?ll be able to rent from Blockbuster and Netflix.

HDTV prices have come down. I was flat-out astonished at a 2004 Hitachi line show when I strolled past?then stopped and became glued to?some tube-based rear-projection sets selling for less than $2000. Their pictures were sharp and seamless, with better black level than most flat panels could muster. You can?t even buy an analog RPTV nowadays, except from the back of a van driven by a guy with a sinister moustache.

Even so, if you?re not into HD, SD is still better than analog. How much better is hard to quantify, since DTV resolution is measured in pixels and analog resolution in lines of horizontal resolution. However, if you could see your DVD player?an inherently standard-def source?delivering signals to both digital and analog sets at the same time, you?d see more than just a slightly crisper image. The difference in color would catch your eye, too. Analog TVs can?t deliver a true red. Watch analog and digital sets reproduce a fire engine, side by side, and you?d be sold?that?s what happened to me!

OK, so SDTV?name notwithstanding?is not really the standard in DTV. That?s HDTV, first and foremost in the hearts of true videophiles. However, SDTV brings digital television to smaller screens as well as the more affordable ones. It increases the diversity of programming, takes you to disaster scenes round the world, and lets you enjoy the gravitas of your favorite talking head without having to inspect the worry lines and craters on his face too closely for comfort. That will make it a power in DTV for years to come.

Have I convinced you never to spend another penny for a non-digital TV? Even if you?re not ready for HDTV? Please post and tell me so. I?m serious. Don?t make me come over there.


Mark Fleischmann is the author of Practical Home Theater (

The views expressed here are solely those of the author and do not reflect the beliefs of Digital Trends.

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