How to Buy a Flat-Screen HDTV

The Big Picture

The supersizing of the American TV continues--but as screens grow ever bigger, tube sizes are going on crash diets. The once-popular 32-inch CRT-based set is a major hog, weighing well over a hundred pounds and requiring a couple of feet of space behind it. Today, thin is in, and flat-panel displays are your best bet for the best picture.

So which kind of flat-panel HDTV should you buy: a plasma model or an LCD set? Both technologies have made it possible to build very shallow, relatively lightweight TV screens with large picture areas. Both carry higher prices than their bulkier brethren, although the gap has shrunk over recent years. In the end, however, you must weigh the differences between plasma and LCD TVs, and determine which works better for your viewing conditions.

The first thing you should know, whether you look at plasma or LCD, is that almost all the sets on the market now are wide-screen models. Translation: Such sets have a 16:9 ratio of screen width to screen height (also referred to as the aspect ratio), which is the standard for HDTV and very close to the ratio used for most modern movies. As a result, the displays are more rectangular than the traditional, almost-square 4:3 sets of the past.

You can find the latest prices on both plasma and LCD TVs in PC World's Shop and Compare center.
Plasma

Essentially all current plasma displays offer HDTV resolution. Screen sizes begin at 42 inches diagonal and typically range up to about 70 inches (occasionally moving up to the downright ridiculous 150-inch sets that companies trot out for trade shows). Prices start at around $1000 and can reach about $15,000.

You get what you pay for in plasma, which means you can't expect to see the same picture quality from a $999 42-inch display that you would from a same-size model selling for $2000, a more typical price. The budget model will usually have lower contrast and poorer reproduction of black and of dark grays, yielding a picture with less punch and detail. A bigger problem with a bargain set is that it may do a worse job of upconverting regular standard-definition (SD) TV programs and DVDs to its native resolution. The resulting picture could look softer, coarser, or noisier than if it had better processing.

The most expensive plasmas in a given screen size are typically 1080p models, which offer 1920 by 1080 resolution. Whether this provides a visible improvement in picture quality over lower but more typical plasma resolutions, such as 1366 by 768 or 1024 by 768, depends on screen size and viewing distance. The smaller the screen, the closer you must be to it to see the benefit of a higher display resolution. For example, with a 50-inch screen you would have to sit within about 10 feet to perceive the difference between 1080p and 1366 by 768.

Like CRTs, plasmas use phosphors to generate light, which means they can be subject to "burn-in"--or, at least, the older plasma sets are susceptible. Burn-in occurs when a static image stays on the screen for a long time; for example, it could be the score box for a ballgame on ESPN, the health meter in a video game, or an annoying network logo that squats in the corner of your screen.

Fortunately, you can minimize the risk by keeping contrast and brightness settings reasonable (virtually all TV sets come out of the box with their contrast, brightness, color, and sharpness controls turned up too high) and by using stretch modes to fill the screen when you're watching 4:3 programming. And for the most part, today's TVs use pixel-shifting strategies that continually move the image on the screen in imperceptibly tiny increments to help prevent burn-in. Such technology should help--that is, unless you plan to watch NCAA March Madness nonstop. Then you have bigger issues.

One last thing to bear in mind with plasma sets is the audio. Most sets now come with speakers either built in or attached to the sides or bottom of the panel, but some remain strictly video displays with neither speakers nor any integrated TV tuner. In such cases you will need to factor those additional costs into your home-theater budget.

You can find the latest prices on plasma TVs in PC World's Shop and Compare center.
LCD

LCD screens range from desktop-friendly 15-inch models up to 70-inch wide-screen wonders complete with speakers and TV tuners. At screen sizes smaller than 42 inches, HDTV LCDs still come at a premium price, but the category is falling into a much more reasonable range. A 32-inch high-definition LCD, for instance, could cost anywhere from about $600 to $2000 depending on its manufacturer and features. (A 32-inch wide-screen display has about the same screen height as a 27-inch TV with a conventional 4:3 aspect ratio.) Once you start craving something larger than 50 inches, though, LCD shopping becomes a little more cost-prohibitive.

LCDs are continuing to play catch-up with plasma models in visual performance. LCD sets often come under criticism for having lower contrast ratios than their plasma counterparts do, as they have a tougher time reproducing deep black and dark grays. That's saying nothing of slower screen response times (aka the refresh rate), which causes on-screen blurring with fast-moving action scenes; sports and video-game fiends are the people most likely to find that problematic.

However, new advances in LCD technology are attempting to resolve the refresh-rate issue. We're seeing more models that refresh the display 120 times per second instead of the standard 60. Sets accomplish this by interpolating between frames to create new frames with pixels illuminated at levels midway between those of the preceding and succeeding real frames--in other words, by faking it. If you're buying a new LCD HDTV, make sure that it has this 120-Hz feature.

LCDs are often one to several inches thicker than plasmas and have a somewhat narrower effective viewing angle. (Plasmas, like CRTs, are easily viewable from well off to the side and do not exhibit any change in brightness as you stand up or sit down.) On the other hand, LCDs are completely immune to burn-in, are easier to view in brightly lit rooms, and more often include all the standard features of a conventional TV. LCDs also run cooler than plasmas, minimizing the need for potentially noisy cooling fans.

Another bonus of LCDs is that they give you the freedom to set them up wherever you please. LCDs work equally well in the dark or in bright-light situations. Or maybe you want to have your TV serve double duty as a huge monitor. LCD panels are light--way lighter than plasmas of the same size--and won't require a team of Clydesdales to haul between rooms.