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The TV You Want Today
HDTVs are evolving fast. From new smooth-motion technology to 'green' energy-conserving capabilities, we’ll tell you the features you’ve got to have on your next set.
When you stroll into your local store to shop for a new TV, dozens of big, glossy screens will greet you, each one trying to draw you in with its bright, colorful pictures. And a bewildering bevy of new features promise a multitude of benefits. Which ones will make a difference in what you watch and in how it looks on the screen? We'll help you sort out what's important. (If you haven't bought an HDTV before, see our previous article package on setting up an HDTV.)
The Changing World of Television
It's official: The (television) world is flat. The market has just about completed the transition from the large, heavy, cube-shaped, standard-definition CRT (picture-tube) television set to the sleek, thin, light, high-definition flat-panel set. According to market research firm DisplaySearch, worldwide shipments of flat-panel televisions shifted from about 5 percent of all sets in early 2004 to nearly 75 percent of the total last spring. In terms of revenue, flat panels now account for more than 90 percent of the worldwide television market. The Consumer Electronics Association says that 52 percent of U.S. households have an HDTV today. And now that the digital transition is complete, HDTV adoption continues apace.
For many shoppers, this year's television purchase may bump a previously purchased HDTV down to some other area of the house, such as the kitchen or a bedroom. But whether this is your first HDTV set or your third, it pays to get a model that's packed with all of the latest features. You'll likely find some eye-popping HDTV deals this holiday season, but don't expect prices to plummet, even if HDTV prices today are 20 percent lower than they were last year. According to DisplaySearch analyst Paul Semenza, the LCD panels used in HDTVs are actually getting more expensive. So far, prices of models on store shelves haven't reflected this shift--but it could inhibit the deep discounts that often appear during a holiday buying season.
Another recent trend is full-resolution HDTVs: All but a few entry-level, low-cost models with screen sizes greater than 40 inches have the 1920-by-1080 resolution of "full HD" (1080p). At smaller screen sizes, 720p remains common: On Best Buy's Web site, I found that 18 of the 35 sets between 30 and 39 inches were 720p, including models from LG, Panasonic, Samsung, and Sony.
40" Samsung LN40B650T1f: It's the priciest 40-inch model on our Top 5 chart of 40-to-42-inch HDTVs, but this television offers first-rate picture quality, along with a slew of ports for Internet features and other network connections, all while being very usable.
Beyond entry-level sets, today's HDTVs differentiate themselves with features that can enhance your viewing experience and improve the TV's performance. Several capabilities--such as fast-motion response times and LED backlighting--that were once exclusive to super-pricey high-end models are now showing up in more-affordable mainstream units. But what do these new features mean, and will they make a noticeable difference in your viewing? Which features are merely nice to have, and which ones are worth paying extra money to get?
(Note: For this feature overview and our latest roundup of HDTVs, the PC World Labs developed a new, up-to-date suite of tests, described in "How We Test HDTVs.")
In Video: How to Buy a Flat-Screen TV
Rising Refresh Rates
According to DisplaySearch, about half of all LCD HDTVs with 40-inch or larger screens now have refresh rates of 120Hz or higher. It took a couple of years for 120Hz to reach the mainstream, but today only entry-level and economy models at these large sizes have the standard 60Hz refresh rate. The picture changes for sets under 40 inches, though: DisplaySearch says that among all such LCDs shipped in the second quarter of 2009, only 14 percent were capable of 120Hz. The company expects that figure to grow to 24 percent by the year 2013.
Some manufacturers have made a full-on push to 120Hz. Sony, for example, has only one series--the Bravia S5100--that doesn't have 120Hz or 240Hz models.
Note the emphasis here on LCDs (versus plasma screens): Since LCDs have the lion's share of the flat-panel market at more than 90 percent, it makes sense that they get most of the attention. But LCD technology has a known issue with fast motion, stemming from the fact that it relies on moving tiny molecules around to block or to transmit the light from the panel's backlight. And these molecules need time to move from one position to another. As a result, traditional panel designs ran into a problem with motion blur. Commonly, the leading and trailing edges of a fast-moving object in an image looked soft, an unwelcome artifact--and not just for hockey fans trying to follow a speeding puck on the screen.
Panel manufacturers found that changing the cell structure and the formulations of liquid crystal material wasn't enough to overcome this problem: The trick was to refresh the image twice as often, doubling the refresh rate from 60 to 120 times a second. In addition, manufacturers improved their televisions' controlling circuitry so that it would look at the two original frames in the 60Hz image stream, and interpolate a new frame to provide an intermediate image.
This approach produced a marked improvement over traditional 60Hz sets, one that's well worth the extra investment in a set with a minimum of 120Hz. The price difference has narrowed, but you can still expect to pay approximately $100 to $200 more to step up to an HDTV set with this feature in the 40- to 42-inch range. It's a must-have feature if you plan to watch sports, but any content that includes panning scenes and fast action will benefit from this technology.
If 120Hz is good, then 240Hz must be twice as good, right? The answer is a lot murkier than that. The manufacturers that offer 240Hz refresh technology are divided into two camps, each with a different approach. Samsung and Sony use a true 240Hz technology, in which (as in 120Hz sets) the controller starts with a pair of frames from the 60Hz content stream--but then creates three additional intermediate frames, not one. This means that for each of the original frames, the set actually displays four frames. (The math changes for 24p signals, such as those piped out by Blu-ray Disc players, but the concept is similar.)
Adding these extra frames causes the liquid crystal material to move more quickly than it otherwise would, which in turn reduces the blur effects. The difference may be noticeable compared with 120Hz, but in our tests it wasn't as dramatic as the difference between 60Hz and 120Hz, even when we looked at the sets side by side. As such, 240Hz is probably not worth paying a lot more for over the cost of a 120Hz model. (Right now, the jump from 120Hz to 240Hz is about $300 to $600, a large premium compared with the step from 60Hz to 120Hz.)
LG 42LH50
LG approaches 240Hz by a different path: Its models with 240Hz performance generate one interpolated frame for each of the standard 60Hz frames, just as 120Hz models do, but they flash their backlights twice for every frame. Thus, 60 original frames plus 60 more interpolated frames make 120 frames, and then the backlight flashing twice for each frame yields 240 flashes per second. Like a strobe light in a disco dance hall, the flash of the backlight helps freeze the action on the screen and reduce motion blur. But this eye trick still presents only 120 frames per second, so asserting that its reÂÂfresh rate is faster than 120Hz rests on rather shaky science.
Panels with 120Hz (or faster) refresh rates have one additional benefit: Most television programming is recorded at 30 frames per second (fps), which is easy to double for the 60Hz refresh rate that most HDTVs have used. Movies, however, are filmed at 24 fps, which poses problems for technicians seeking to digitize them for DVD or broadcast formats. To fit the 30-fps timing, every four frames of movie film must be stretched to fit five frames of video. The process employed to achieve this, called "3:2 pulldown," uses two interlaced fields of the first film frame and then three interlaced frames of the next frame to produce the stretch.
This awkward conversion can create a motion artifact called "judder," a jerkiness or slight stutter visible in the finished image. But since 120Hz, unlike 60Hz, is an even multiple of 24, these panels can display 24-fps material without requiring any conversion; each frame just gets shown five times.
Note also that plasma does not have this problem. The individual plasma pixels can actually turn on and off much faster than an LCD pixel; in fact, Panasonic has taken to describing their panels as "600 Hz". Plasma needs this extra speed because a pixel can only be on or off, and so must be turned on and off rapidly during each frame of an image to create the correct shade of color. So in theory, motion blur is not a problem for plasma models. However, the PC World Labs' tests showed that, at least in the case of the two plasma models we tested from Panasonic--the TC-PS461 and the TC-P42X1--some plasma sets could learn a thing or two from LCDs.PC World
HDTVs are evolving fast. From new smooth-motion technology to 'green' energy-conserving capabilities, we’ll tell you the features you’ve got to have on your next set.
When you stroll into your local store to shop for a new TV, dozens of big, glossy screens will greet you, each one trying to draw you in with its bright, colorful pictures. And a bewildering bevy of new features promise a multitude of benefits. Which ones will make a difference in what you watch and in how it looks on the screen? We'll help you sort out what's important. (If you haven't bought an HDTV before, see our previous article package on setting up an HDTV.)
The Changing World of Television
It's official: The (television) world is flat. The market has just about completed the transition from the large, heavy, cube-shaped, standard-definition CRT (picture-tube) television set to the sleek, thin, light, high-definition flat-panel set. According to market research firm DisplaySearch, worldwide shipments of flat-panel televisions shifted from about 5 percent of all sets in early 2004 to nearly 75 percent of the total last spring. In terms of revenue, flat panels now account for more than 90 percent of the worldwide television market. The Consumer Electronics Association says that 52 percent of U.S. households have an HDTV today. And now that the digital transition is complete, HDTV adoption continues apace.
For many shoppers, this year's television purchase may bump a previously purchased HDTV down to some other area of the house, such as the kitchen or a bedroom. But whether this is your first HDTV set or your third, it pays to get a model that's packed with all of the latest features. You'll likely find some eye-popping HDTV deals this holiday season, but don't expect prices to plummet, even if HDTV prices today are 20 percent lower than they were last year. According to DisplaySearch analyst Paul Semenza, the LCD panels used in HDTVs are actually getting more expensive. So far, prices of models on store shelves haven't reflected this shift--but it could inhibit the deep discounts that often appear during a holiday buying season.
Another recent trend is full-resolution HDTVs: All but a few entry-level, low-cost models with screen sizes greater than 40 inches have the 1920-by-1080 resolution of "full HD" (1080p). At smaller screen sizes, 720p remains common: On Best Buy's Web site, I found that 18 of the 35 sets between 30 and 39 inches were 720p, including models from LG, Panasonic, Samsung, and Sony.
40" Samsung LN40B650T1f: It's the priciest 40-inch model on our Top 5 chart of 40-to-42-inch HDTVs, but this television offers first-rate picture quality, along with a slew of ports for Internet features and other network connections, all while being very usable.
Beyond entry-level sets, today's HDTVs differentiate themselves with features that can enhance your viewing experience and improve the TV's performance. Several capabilities--such as fast-motion response times and LED backlighting--that were once exclusive to super-pricey high-end models are now showing up in more-affordable mainstream units. But what do these new features mean, and will they make a noticeable difference in your viewing? Which features are merely nice to have, and which ones are worth paying extra money to get?
(Note: For this feature overview and our latest roundup of HDTVs, the PC World Labs developed a new, up-to-date suite of tests, described in "How We Test HDTVs.")
In Video: How to Buy a Flat-Screen TV
Rising Refresh Rates
According to DisplaySearch, about half of all LCD HDTVs with 40-inch or larger screens now have refresh rates of 120Hz or higher. It took a couple of years for 120Hz to reach the mainstream, but today only entry-level and economy models at these large sizes have the standard 60Hz refresh rate. The picture changes for sets under 40 inches, though: DisplaySearch says that among all such LCDs shipped in the second quarter of 2009, only 14 percent were capable of 120Hz. The company expects that figure to grow to 24 percent by the year 2013.
Some manufacturers have made a full-on push to 120Hz. Sony, for example, has only one series--the Bravia S5100--that doesn't have 120Hz or 240Hz models.
Note the emphasis here on LCDs (versus plasma screens): Since LCDs have the lion's share of the flat-panel market at more than 90 percent, it makes sense that they get most of the attention. But LCD technology has a known issue with fast motion, stemming from the fact that it relies on moving tiny molecules around to block or to transmit the light from the panel's backlight. And these molecules need time to move from one position to another. As a result, traditional panel designs ran into a problem with motion blur. Commonly, the leading and trailing edges of a fast-moving object in an image looked soft, an unwelcome artifact--and not just for hockey fans trying to follow a speeding puck on the screen.
Panel manufacturers found that changing the cell structure and the formulations of liquid crystal material wasn't enough to overcome this problem: The trick was to refresh the image twice as often, doubling the refresh rate from 60 to 120 times a second. In addition, manufacturers improved their televisions' controlling circuitry so that it would look at the two original frames in the 60Hz image stream, and interpolate a new frame to provide an intermediate image.
This approach produced a marked improvement over traditional 60Hz sets, one that's well worth the extra investment in a set with a minimum of 120Hz. The price difference has narrowed, but you can still expect to pay approximately $100 to $200 more to step up to an HDTV set with this feature in the 40- to 42-inch range. It's a must-have feature if you plan to watch sports, but any content that includes panning scenes and fast action will benefit from this technology.
If 120Hz is good, then 240Hz must be twice as good, right? The answer is a lot murkier than that. The manufacturers that offer 240Hz refresh technology are divided into two camps, each with a different approach. Samsung and Sony use a true 240Hz technology, in which (as in 120Hz sets) the controller starts with a pair of frames from the 60Hz content stream--but then creates three additional intermediate frames, not one. This means that for each of the original frames, the set actually displays four frames. (The math changes for 24p signals, such as those piped out by Blu-ray Disc players, but the concept is similar.)
Adding these extra frames causes the liquid crystal material to move more quickly than it otherwise would, which in turn reduces the blur effects. The difference may be noticeable compared with 120Hz, but in our tests it wasn't as dramatic as the difference between 60Hz and 120Hz, even when we looked at the sets side by side. As such, 240Hz is probably not worth paying a lot more for over the cost of a 120Hz model. (Right now, the jump from 120Hz to 240Hz is about $300 to $600, a large premium compared with the step from 60Hz to 120Hz.)
LG 42LH50
LG approaches 240Hz by a different path: Its models with 240Hz performance generate one interpolated frame for each of the standard 60Hz frames, just as 120Hz models do, but they flash their backlights twice for every frame. Thus, 60 original frames plus 60 more interpolated frames make 120 frames, and then the backlight flashing twice for each frame yields 240 flashes per second. Like a strobe light in a disco dance hall, the flash of the backlight helps freeze the action on the screen and reduce motion blur. But this eye trick still presents only 120 frames per second, so asserting that its reÂÂfresh rate is faster than 120Hz rests on rather shaky science.
Panels with 120Hz (or faster) refresh rates have one additional benefit: Most television programming is recorded at 30 frames per second (fps), which is easy to double for the 60Hz refresh rate that most HDTVs have used. Movies, however, are filmed at 24 fps, which poses problems for technicians seeking to digitize them for DVD or broadcast formats. To fit the 30-fps timing, every four frames of movie film must be stretched to fit five frames of video. The process employed to achieve this, called "3:2 pulldown," uses two interlaced fields of the first film frame and then three interlaced frames of the next frame to produce the stretch.
This awkward conversion can create a motion artifact called "judder," a jerkiness or slight stutter visible in the finished image. But since 120Hz, unlike 60Hz, is an even multiple of 24, these panels can display 24-fps material without requiring any conversion; each frame just gets shown five times.
Note also that plasma does not have this problem. The individual plasma pixels can actually turn on and off much faster than an LCD pixel; in fact, Panasonic has taken to describing their panels as "600 Hz". Plasma needs this extra speed because a pixel can only be on or off, and so must be turned on and off rapidly during each frame of an image to create the correct shade of color. So in theory, motion blur is not a problem for plasma models. However, the PC World Labs' tests showed that, at least in the case of the two plasma models we tested from Panasonic--the TC-PS461 and the TC-P42X1--some plasma sets could learn a thing or two from LCDs.PC World
