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November 21, 2005

HDTV: Part II

This is the second of two Tech Talk issues devoted to high-definition television (HDTV). The first touches on issues like resolution, interlacing, widescreen format, and content options. If you missed it, HDTV Part I is available at the Reference desk.

What kind of HDTV should I get?

Unfortunately, this is not an easy question to answer. There are many types of HDTVs, and each has relative strengths and weaknesses. Keep in mind that even a mediocre HDTV will provide better image quality than a great traditional television. Here are a few types of HDTV sets you may wish to consider:

• CRT: Chances are, your current standard-definition TV uses a CRT (cathode ray tube) to display its image. HDTVs that use this time-tested technology have excellent picture quality. There are some problems, though. The largest screen you can get is about 34 inches on the diagonal, which is smaller than most people prefer. Also, they are extremely heavy, easily weighing over 150 pounds. They also are subject to burn-in, where long-term display of static images (such as some video game graphics) can damage the screen. Still, if you don't mind the bulkiness and weight, a CRT HDTV can provide a great picture for a small room.
  
• Plasma: This screen technology almost single-handedly made thin televisions a hot commodity. Much lighter than their standard CRT brethren, plasma screens are sometimes mounted directly to the wall, giving a sleek appearance and taking up little, if any, floor space. They are bright and have very good image quality, but are expensive. Like CRT screens, they can be damaged by burn-in. For the ultimate image quality in a slim package, plasma is the way to go.
  
• LCD: With the incredible success of LCD (liquid crystal diode) displays in the computer market, it's not surprising that they would be adapted to television use. LCDs, like plasma displays, are very thin and light, and their relatively low price range makes them appealing. Image quality is good, and LCD TVs are safe for use with video games and computers, as they are not subject to burn-in. On the negative side, they don't reproduce pure black very well, and "off-axis" viewing is degraded. This means that unless you're in one of the seats directly facing the LCD panel, you won't get an optimal image. Finally, some LCDs may not display quickly-moving images as clearly as other types of sets. Because of these drawbacks, most experts give plasma the edge over LCD. However, with every generation, this quality gap narrows.
  
• DLP: Digital light processing (DLP) is a complex technology invented by Texas Instruments involving thousands of tiny computer-controlled mirrors and a spinning color wheel. The picture quality of DLP sets is excellent, providing good black reproduction and brightness. They are fairly thin, though not in the same ballpark as LCD or plasma. DLP sets offer consumers a relatively inexpensive way to get a large-screen HDTV set. The biggest problem with DLP TVs is something called the "rainbow effect." The combination of spinning wheel and mirrors can cause some people to see multi-colored lines in their peripheral vision when tracking movement across the screen. To find out whether you will experience this effect, you should watch varied content on a DLP set for several minutes. If you don't see the rainbow effect, DLP sets can offer large screens for a bargain price.

What's the best connection type? HDMI, DVI-D or component?

HDMI, DVI-D and component video are possible types of connections on the back of your HDTV, each with a different cable configuration. Both HDMI and DVI-D are digital, each providing the best possible picture quality. HDMI cables also carry audio information, so if you're seeking to minimize clutter, you might look for this. Component connections are analog in nature, which means their signal will not be quite as pristine as the other two (though still very high in quality). Ideally, an HDTV set will have multiple input types, to avoid compatibility problems with equipment.

How big a screen should I get?

In general, get the largest screen you can afford. A recent Consumer Reports survey found that as screen size increases, HDTV owner satisfacation increases. For optimal viewing, you should sit at a distance of roughly twice the diagonal measurement of the screen. With a 42-inch HDTV, you should sit about seven feet (84 inches) away. If your seat is too far from the screen, or the screen is too small for the room, you will not be able to see all of the detail in the image, partially eliminating the benefit of having a high-definition television set.

Are there downsides to this technology?

In order to take advantage of the increased picture quality of HDTV, you'll need to update your television. These televisions are less expensive than in the past, but most still carry a price tag well over $1,000. If you plan to get your content with an antenna, it can be difficult to get a strong signal. Unlike analog, where you can try to ignore the static of a weak signal if necessary, digital TV tuners will give you no picture at all unless the reception is good. Consequently, you'll need to experiment with various antennas to find one which works for your location.

Final Thoughts
HDTVs are coming down in price, but they still remain costly relative to standard TVs. Each individual or family needs to decide whether upgrading to HDTV makes sense, but the visual impact of HDTV is undeniably impressive.

Resources

Print

• HDTVs: The Price is Right. Consumer Reports, December 2005, pp. 22-29.


• Screen Gems: Top Performers in Digital TV. Consumers Digest, October 2005, pp. 33-40.
  (ask for these issues at the Reference desk)
  

Web

• HDTV from Wikipedia:
  
• What is digital television? from About.com
  
• HDTV Primer
  
• The HDTV Difference: This interactive guide to HDTV and digital television is a part of Samsung's commercial site, but it provides a lot of good general information for consumer.
  
• Ten HDTV Myths: from PC World Magazine
  
• Antenna Web: Advice on selecting the best HDTV antenna for your location.

Posted by moetting at 04:51 PM | Comments (0)