HDTV

HDTV Fundamentals

Not that long ago, TV was TV. There was one main technology (direct-view cathode ray tube, or CRT) and one broadcasting format (480i). Now, however, there are five different types of TV and a number of different technologies. There are also lots and lots of different ways to format a TV signal. In fact, the Advanced Television Systems Committee (ATSC), which is the organization that created the digital broadcasting standards for the United States, allows 18 in all. Fortunately, there are "only" five that you really need to be concerned with:

480i Standard Definition (SD). To create an SD picture, 480 horizontal lines of image information are sent in an interlaced (that's what the “i” stands for) format. Each frame (or image) of an interlaced TV signal is actually made up of two fields, one consisting of the odd lines of the image and the other the even lines. The two fields are displayed one after the other by the TV at a speed that's so fast that the eye sees only one image. SD images have the familiar 4:3 aspect ratio.

480p Enhanced Definition (ED). Like standard definition, a 480p EDTV image is made up of 480 lines of information; however, they are displayed in a progressive format (hence the 'p'), which means the entire frame is displayed at one time. While there is no more image information than in an SD picture, the image appears sharper and smoother because the artifacts caused by interlacing are eliminated. While ED sets cannot display HDTV signals in their full resolution, they are usually widescreen.

720p HDTV. The lowest of the high-definition resolutions, a 720p image is made up of 1280 x 720 pixels displayed progressively. While other formats display more picture information, many critics say that at normal viewing distances, this format presents a picture that's just as appealing and even more film-like. Among major programmers, only ABC and its subsidiaries (including ESPN and ESPN2) and FOX distribute content in 720p.

1080i HDTV. This format places 1920 x 1080 pixels of picture information on the screen (in an interlaced format) for a vivid and sometimes breathtaking picture. Most broadcast, cable and satellite HD providers use this format.

1080p HDTV. Many new HDTVs are capable of accepting 1080i signals and, after some internal processing (called de-interlacing), these TVs can display the signals in a progressive format for the richest images of all. Most of these sets (but not all) are now also capable of accepting 1080p signals from high-quality sources such as Blu-ray DVD players, some (but not all) HD-DVD players and video game consoles (such as the Sony PlayStation 3). Because it takes up so much bandwidth, it is unlikely that any broadcaster or other programming provider will be distributing HD material in 1080p in the foreseeable future. So right now, 1080p is mainly a media format.

Note that while ATSC-compatible tuners must be able to receive all ATSC formats, the TVs themselves are free to take those signals and scale them to fit their native resolutions, which, for manufacturing reasons, don't always match up exactly with the ATSC standards. That's especially true of LCD and plasma TVs.

The bottom line, however, is that regardless of the resolution, HDTV looks terrific compared to SD or EDTV, reviewers say. But it doesn't take an expert to see the difference. If you look at an SDTV next to a HDTV in a store, you'll immediately notice why high-definition TV is so compelling.

The other issue with HDTV is content, but that is becoming less and less of a concern. Programming is much more available, and the major networks now broadcast virtually all of their prime-time programming in HD. There are also quite a few HD cable networks, and that number continues to grow. Most cable and satellite companies are in a race to add HD networks to attract and retain subscribers. All of that, coupled with the fact that prices for HDTVs are dropping fast, means that HDTV is no longer merely for videophiles.

Simply buying an HDTV does not automatically mean you get HDTV images on your screen. The hardware is only one part of the equation. To get the high-definition programming signals, you need to subscribe to a digital high-definition cable or satellite service. Alternatively, you can receive HDTV broadcasts "over-the-air" with a roof-mounted antenna, provided you are within range of a transmission tower. Of course, you won't get premium channels this way, but you can access the local affiliates of the major networks. AntennaWeb.org is a great website that lets you plug in your home address to see what kind of over-the-air broadcasts are available in your area.

With all TVs now required to have digital tuners, HD-ready sets (those that can display HD images but lack an integrated digital tuner) are disappearing from the market, with some notable exceptions. The law requiring new TVs to have a digital tuner does not apply to monitors -- those TVs that have no tuner at all. Tunerless monitors can be a good choice for those who get all of their TV from cable or satellite, but you'll need an external tuner to get any over-the-air programming.

Some HDTVs are compatible with CableCards. These TVs don't require a cable box to receive premium programming from cable companies. You plug the digital cable feed directly into the TV, and your cable company installs a CableCard (which goes into a slot on the TV). The CableCard de-scrambles the channels to which you've subscribed. However, experts' reactions to first generation CableCards have been lukewarm, mostly because you can't use any of cable's interactive features. You can't order movies on demand with the remote or access the interactive programming guide. CableCards have really never caught on -- and many manufacturers have removed that input from their TVs, especially from entry-level models.

In addition, some digital tuners are QAM-capable. QAM, which stands for Quadrature Amplitude Modulation, is the transmission scheme cable companies use to distribute digital TV signals. A QAM tuner can allow you to receive any unscrambled, basic programming you subscribe to without a cable box or CableCard. An external box or a CableCard is still required for premium programming, however.

While the analog broadcasting system will be gone for good in February 2009, those with older, non-digital sets will not be left completely in the dark. Cable companies are being required to provide local broadcasts to analog TV owners who subscribe to basic cable (which doesn't usually require a set-top box) until at least 2012. Providers have the choice of converting the digital broadcasts to analog for distribution on their systems, or providing all of their customers with free converter boxes.

In addition, the government has set up a voucher program that will help offset some of the cost of an external digital tuner for those who need them. The program goes into effect Jan. 1, 2008 and provides $40 coupons that can be used toward the purchase of up to two analog to digital converters. See Best Research for more information.

TYPES OF HDTVs

There are five main types of display technology for HDTV. Plasma and LCD TVs draw lots of attention, as these two types are wall-mountable. LCD flat-panels come in smaller, less expensive sizes, while plasma TVs are only available in sizes larger than 37 inches. The most affordable HDTVs are standard, tube-based TVs. These are heavy and bulky, and they don't come in sizes larger than 30 inches. They are also disappearing fast in the marketplace. Rear-projection TVs have come a long way from the huge cabinets you might remember. These newer microdisplay models cut down on the depth, but still deliver big screens up to 70 inches. New models with even shallower cabinet depths are now available. A last option is hooking a front projector up to your cable feed and projecting the image on a wall or, preferably, on a screen.

Standard tube-based TVs

Experts say that despite newer technology, good old conventional fat-and-heavy direct-view CRT TVs give you a reliably great picture, and they're less expensive than other types of HDTVs. While conventional tube-based TVs are still popular, falling sales and closing picture-tube plants around the world have led many makers to reduce the number of sets they offer, or even eliminate them from their line-ups completely. Sony is the latest company to abandon CRT technology; they completely eliminated their standard TV offerings earlier this year. Also, because these heavy TVs have a big footprint and require a lot of depth, the largest size standard HDTV you'll see is 30 inches (measured diagonally), and most are smaller.

While other types of TVs each have some annoying issues, conventional HDTVs are virtually trouble-free. They also have a longer lifespan than plasma TVs and don't need any special maintenance. Rear-projection TVs, for instance, need to have their lamps replaced about every 6,000 hours. Tube-type TVs may not be as cutting edge, but they are certainly easy to use and reliable.

Among current-production CRT HDTVs, Samsung’s Slim-Fit line of standard televisions have drawn mixed reviews. Picture quality is generally excellent, and these sets use a CRT with an innovative design to reduce cabinet depth considerably -- just over 16 inches in the 30-inch Samsung TX-T3092WH (*est. $570). However, we’ve also seen user reports of some geometry issues -- vertical and horizontal lines that are not perfectly straight -- on some earlier Slim-Fit HDTVs. But if you want to stick with a well-known manufacturer, these Slim-Fit TVs are pretty much the only option now that Sony has left the market.

Keep in mind that the falling prices of other HDTV technologies have made them increasingly competitive with CRT-type HDTVs. For example, you can get a larger 32-inch LCD TV for just a little bit more that the 30-inch Samsung set.

Flat-panel plasma and LCD HDTVs

Plasma and LCD TVs are only a few inches thick and are wall-mountable. Design-wise, most look terrific hanging on a wall or sitting on a tabletop. Plasma TVs generally come in screen sizes of 37 inches and up (measured diagonally). While the most common sizes are 42 inches and 50 inches, larger plasma displays are becoming more commonplace.

LCD TVs, on the other hand, are available in a much wider range of sizes. The smallest LCD TVs are about 8 inches, and sizes for consumer TVs now go up to 65 inches, with some manufacturers demonstrating sets as large as 108 inches. Smaller LCD flat-panel HDTVs, which start at around 19 inches, are a good choice for bedrooms and kitchens.

While reviews say they are getting close, the picture quality of neither plasma nor LCD yet equals the image you'd get from a conventional CRT-based HDTV. The advantage of plasma and LCD TVs, of course, is a sleek screen that takes up very little space. But note that while they may be thin, larger flat-panel TVs are still quite heavy and wall mounting often requires professional installation.

Smaller LCD TVs have a native resolution of 1366 x 768 pixels. LCD TVs with that resolution can display standard TV, DVDs and 720p HD with no loss of detail, but need to scale down 1080i HD programming. Recently, manufacturers have been rushing 1080p sets to market. These LCD TVs are more expensive than 720p TVs, but they can display every pixel of a 1980 x 1080 HDTV image.

Most 50-inch and larger plasma TVs have 1366 x 768 resolution, but 42-inch plasma TVs typically have a native resolution of just 1024 x 768 pixels, which falls short of the ATSC standard of 1280 x 720. Despite that, industry convention -- which only looks at the horizontal specification when labeling TVs for sale to the public -- allows them to be sold as HDTVs. While this is an issue with some, reviewers say that as a practical matter, few will be able to tell the difference between 1024 and 1280 vertical resolution at normal TV viewing distances. Manufacturers are bringing more and more plasma TVs with 1920 x 1080 resolution to market. However, most 1080p plasmas are considerably more expensive than their 720p counterparts, and more expensive than 1080p LCD sets of the same size.

While experts say the gap is closing, plasma TVs are known for their ability to display dark colors and detail in dark scenes better than LCD. This makes plasma a good choice for movie watching, where dark scenes are common. LCD TVs are brighter, which means LCD may be a better choice for a well-lit setting; plasma TVs can sometimes look washed-out in a bright room.

Plasma screens have wider viewing angles than LCD flat panels. That means you can sit at more of an angle and still get the best picture. With conventional TVs, the picture brightness and color saturation stays the same from virtually any angle. With LCDs, sitting too far to one side will result in a loss of brightness. In addition, LCDs can sometimes leave trails behind fast-moving parts of an image. That's because of the time it takes for LCD pixels to switch color (plasma pixels make the change much faster). Finally, slower LCD switching speeds sometimes cause a loss of detail in fast-moving images. However, technology improvements have made both viewing angle and motion trails less of an issue in better LCD sets, and new technology to address softness in action scenes is included in many of the newest LCD TVs, though we've seen mixed reports of its effectiveness, and even its need.

The most disconcerting issue regarding plasma TVs in the past has been a susceptibility to burn-in. Leaving the same image on the screen too long risked its being etched permanently into the screen, creating a lasting impression. New technology greatly reduces the risk of burn-in, and analysts at PC Magazine say that burn-in is no longer a major concern. Still, it's a good idea not to leave a plasma TV on when you're not watching it. LCDs have no burn-in risk.

While plasma TVs can produce great, cinematic images in a darkened room, they sometimes appear washed out when room lighting is higher. In addition, their top glass is usually much more reflective, though plasma TVs with anti-reflective screens are also available. Because of that, LCD TVs are sometimes a better choice for viewing in areas such as a typical living room where there are windows, making for greater variation in lighting at different times of day or night.

Though some buyers have been concerned about the life expectancy of a plasma TV, the latest models have panels that are rated to last up to 60,000 hours before they lose half their brightness. That translates to over 20 years if you watch TV eight hours a day. Until recently, plasma TV held a price advantage over LCD, but that gap is closing. In addition, if you want 1080p resolution, LCD is currently a less expensive option.

Among the top plasma HDTV models from our report is the 50-inch Pioneer KURO PDP-5070HD (*est. $2,800). While the TV is expensive compared to its direct competition, and offers only 720p resolution, reviews say the Pioneer PDP-5080HD achieves some of the richest, most saturated colors. The TV has lots of features, including an anti-glare screen, a CableCard slot, TV Guide electronic program guide and more. There are lots of inputs -- more than any other HDTV reviewed to date, according to reports -- and each can be tweaked independently. There are also four additional independent picture memories. Reviews say the set is easy to use thanks to its well-laid-out remote control and an excellent on-screen menu system.

If you want a 1080p plasma HDTV, critics say that the Panasonic TH-50PZ700U (*est. $2,450) offers a great blend of value and performance. Picture quality falls a little short of the best efforts from Pioneer, but not by all that much, and the picture is described as crisp, with good blacks, shadow detail and contrast. There aren't a lot of features, but there is an anti-reflective screen coating to cut down problems caused by room lighting, plus an SD memory slot for viewing still photos. In addition, the TV supports Panasonic's EZ Sync HDAVI control system, which lets you control compatible components with a press of the remote's button. While critics generally give the Panasonic TH-50PZ700U good grades, owners seem to be ecstatic as we've seen uniformly positive comments at user review sites across the Internet.

Among LCD TVs, Sony’s BRAVIA line of 1080p HDTVs generally does very well in professional reviews. Models include the 40-inch KDL-40XBR4 (*est. $2,200) , the 46-inch KDL-46XBR2 (*est. $2,750) and the 52-inch KDL-52XBR2 (*est. $3,500). Critics say that although black levels and contrast don’t quite measure up to the best produced by other technologies, they are largely unmatched by any other LCD TV. Features and connectivity are also first rate, and styling is unique, including a bezel that can be exchanged for one of another color (at an additional cost, of course).

Samsung has also received great reviews for its 65F series of 1080p LCD TVs. Unlike many highly-rated LCD TVs, these sets have a high-gloss reflective screen coating that makes them a poor choice for a well-lit room. Some reviewers say the coating seems to make everything look just a little sharper, while others say it can be distracting. Everyone agrees that colors are excellent, and there's a full complement of controls to get things perfect. Blacks and shadow detail that are first rate for an LCD TV. The TV is offered as the 52-inch Samsung LN-T5265F (*est. $2,250) and the 40-inch Samsung LN-T4065F (*est. $1,380) .

Once regarded as a maker of low-end, low-cost electronics, Westinghouse has been turning heads with some of its LCD TVs. One example is the 47-inch Westinghouse Digital TX-47F430S (*est. $1,100) , a high-performance LCD TV that's capable of accepting and displaying 1080p signals at full resolution. While black levels aren't the best available, they are pretty good, and critics say that the overall picture quality is very good. If 1080p is not a concern -- and some critics say it should not be in a smaller-screen LCD TV -- the 37-inch Syntax-Brillian Olevia 537H (*est. $750) is earning some raves as a great budget alternative with very good image quality.

Rear-projection TVs

There are several types of rear-projection TVs (RPTVs) on the market. CRT-based models have the largest cabinets and use the most established technology. While they have a few advantages, these RPTVs are rapidly disappearing and most manufacturers have stopped making them altogether.

Most rear-projection TVs sold today are microdisplays, which get their name from the fact that their cabinets are so much smaller than the CRT RPTVs they have displaced. Currently, there are three microdisplay technologies available: LCD, DLP (Digital Light Processing) and LCoS (Liquid Crystal on Silicon). Most average around 18 inches deep, although new designs with cabinet depths of 14 inches and less are beginning to appear. While that is still thicker than a plasma or LCD screen, a rear-projection television will cost significantly less than the same sized plasma or LCD TV. However, since bulbs need to be replaced every two years or so, there are some ongoing costs. The replacement bulbs cost about $200 each.

One unsettling issue is a higher-than-average repair rate for rear-projection microdisplays. This problem emerged as a factor in large owner-surveys conducted by Consumer Reports magazine. While extended warranties are normally considered a waste of money, getting an extended warranty on an RPTV might not be a bad idea, easing your mind about possible trouble down the road.

Of the three technologies, LCoS draws the most raves. However, it is more expensive than the others and currently used only by a few manufacturers. DLP also gets some great notices for its cinematic blacks, but it suffers from "rainbow effect." This occurs when your eye registers too much of one color, causing you to see a brief flash of solid color. However, rainbow effect is only an issue for a minority of viewers -- many people's eyes don't register the phenomenon at all. That said, DLP rainbows can be a real issue for those few viewers who see them and are bothered by them. Technology improvements (faster color wheels and more color segments) have minimized the rainbow effect in some DLP RPTVs, and DLP sets that use LEDs instead of a lamp and color wheel have eliminated it altogether.

LCD RPTVs are the least expensive microdisplay. While they offer rich, saturated colors, black levels are not as good as those of other technologies, and viewers often complain about a "screen door" effect -- the picture sometimes looks as if it is being watched through a screen door. Some LCD projection sets have improved black levels and minimal screen-door effect.

Among LCoS sets, Sony’s RPTVs generally get the best reviews from critics. The latest generation features some great innovations including a cabinet depth that's 20 percent slimmer than its predecessors. Another is frame sensing, a technology that analyzes the program content and adjusts the display's signal processing to generate the smoothest display. Sony's automatic iris adjustment varies light output based on content. Well received by critics and users alike, current models include the 60-inch Sony KDS-60A3000 (*est. $1,850), 55-inch Sony KDS-55A3000 (*est. $1,700) and 50-inch Sony KDS-50A3000 (*est. $1,530) . One downside is that the A3000 series is relatively devoid of extra features; even picture-in-picture is missing.

For those interested in DLP RPTVs, the 56-inch Samsung HL-T5687S (*est. $1,630) has scored well with critics. This DLP set uses LEDs in place of the color wheel/lamp used in conventional DLP TVs. This eliminates -- or at least greatly reduces -- rainbow effect issues. In addition, the technology eliminates another projection TV shortcoming: limited lamp life. While there are some screen uniformity problems -- some areas of the screen are brighter than others -- reports say that blacks and color are both excellent.

Front projectors

Once a part of only the most expensive home-theater setups, digital projectors have dropped in price to where they are now a practical option. But while these projectors are capable of delivering the largest images (over 100 inches) at the lowest cost (on a dollars-per-inch basis), critics note that they are not perfect for everyone or every situation.

For one thing, they demand more from the user. To complete your home theater, you need to supply a screen (for best results) and an external audio system. Also, since projectors don't include their own integrated tuner, you need to supply an external one or a signal from a cable or satellite TV box.

The second issue is light levels. For the most part, digital projectors are only suitable for use in rooms where lighting can be completely controlled. That's because even a little bit of ambient light can wash out the image. This is less of an issue with brighter projectors, but still, front projectors are not the best choice for daylight viewing in a sunny room. Like RPTVs, front projectors can use LCoS, DLP or LCD technology.

The biggest news in front projection has been the tremendous price cuts. Three years ago, a 1080p projector would have cost around $30,000. Today, a strong performing 1080p projector can be had for under $3,000. One example is the Optoma HD80 (*est. $2,700) , a 1080p DLP projector that has reviewers doing cartwheels over both the price and performance. Reports say that black levels, sharpness and color are truly first rate. The only drawbacks are finicky installation requirements and brightness, that while adequate, isn't the highest available.

For those on tighter budgets, the Optoma HD72 (*est. $1,420) has earned praise from all quarters. Reviews say that the 720p DLP front projector offers a hard-to-beat combination of excellent performance and aggressive pricing.

Important Features: HDTV

Experts say you should consider the following issues if you're eyeballing an HDTV, no matter whether you choose a conventional, flat-panel, a front-projection or rear-projection set:

• Pick your technology first. LCD, plasma, rear projection, front projection and standard TVs all have their advantages and disadvantages. Consider your viewing habits and your room to see which will work best for your situation, then zero-in on the right HDTV.

• Look for an HDMI input. Found on most current cable and satellite receivers, DVD players and DVD recorders, the HDMI (High-Definition Multimedia Interface) connection keeps the incoming signal all-digital, avoiding degradation that can occur if the signal is converted from digital to analog and back again, as happens when other connections are used. HDMI can carry digital video and audio signals. It is also compatible with HDCP (High-Bandwidth Digital Content Protection), a copy-protection method that in the future could prevent you from making high-definition copies of some HD programming. Someday you might be able to view copy-protected programs in full HD resolution only through an HDCP-compliant connection. Instead of an HDMI port, some sets provide an HDCP-compliant DVI connection. That connection carries digital video, but not digital audio. An HDCP-compliant DVI connection can accept an HDMI input via an adapter cable.

• Match TV size to the size of your room. Because high-definition TVs have higher resolutions than conventional TVs, you can sit closer than you normally would. That means you can get away with a bigger screen. Even so, 60-inch screens that look great in a showroom may overwhelm a smaller room.

• Check around price-wise. In our research, we found price differentials of $1,000 or more from retailer to retailer for some TVs, so it pays to look around. In addition, some manufacturers, such as Sharp and Pioneer, have restrictive policies regarding Internet sales. If you don't buy from an authorized Internet retailer, you'll most likely void your manufacturer warranty. Many retailers offer a replacement warranty, however, so be sure to ask.

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