LG Electronics 42LP1D LCD HDTV and 42PX4D Plasma HDTV

LCD and plasma go head to head. . .sort of.

The 42-inch display size has become a battleground of sorts between liquid crystal displays (LCDs) and plasma displays. Ironically, the older technology, LCD, is the relative newcomer here. Prices on both sides have dropped quickly. You can now buy an HDTV (qualified by both resolution and the integration of a tuner) for just a little more than the price of an EDTV just over a year ago. LG Electronics is one of the only companies with their feet on both sides of this issue (the other biggie being their across-the-Han rival, Samsung). LG also makes an LCD in a 42-inch size, which is rather rare. Most are either smaller or slightly larger. There are lots of questions and misinformation about these technologies, so hopefully we can clear a lot of that up. This isn't a true head-to-head Face Off; let me tell you why.

It's (Almost) All in the Black Level
Of all of the video Face Offs we've done over the last few years, the winners had one thing in common: black level. They either had the best black level or were tied with another display for the best black level. So, in a Face Off between an LCD and a plasma, it's pretty safe to say that the plasma would win. Even the LCD panels with the deepest black levels are still noticeably higher than the black levels that plasmas can produce. So, if that's what you're looking for, look no further. Rarely, though, is black level the whole story.

What and Where
The most important question you have to ask yourself before you start looking for a display is how you're going to use it. If you answered "To watch TV, stupid!" roll up this magazine and hit yourself with it. We only need one smart ass here, and it's obviously me. How you use your display is crucial to which flat-panel technology you should consider.

For example, say you're looking to replace the TV in your family room with something sexy and flat. A poster of the cast of Lost is probably out, so you have your eyes set on a flat panel. Most family rooms are pretty brightly lit, either by fashionable lighting from your local Ikea or by big widows and doors. If this is the case, and you intend to watch TV during the day, plasma isn't the best choice. There are several reasons for this, the first being reflections. The front of a plasma is glass. . .reflective, shiny glass. (LCD panels tend to be less reflective due to their polarizing nature.) In a room with a lot of ambient light, the image on a plasma is harder to see. To counter this, you tend to turn the contrast all the way up.

This leads to the other big reason that plasma isn't the best choice for a room with lots of ambient light. Plasmas have phosphors, which glow so that you can see a picture. The adage "twice as bright, half as long" comes into play here. For the best longevity of a plasma, you don't want to run it full-bore all the time. Partial-bore will be just fine. Turning the contrast all the way up is also a great way to invite burn-in. As you probably know, burn-in happens when a phosphor doesn't like getting turned off and stays partially lit for a time after it was instructed to go out. On the screen, this appears as a ghost of whatever image was on the screen before. Plasmas are getting much better at preventing burn-in (either by using different phosphors, different gas, or some electronic gadgetry). If you turn your contrast control down, though, this will help even more.

Or, say you have a dedicated home theater room. When you watch something in there, it's usually dark. In that case, an LCD isn't a good choice. LCDs are bright. Generally, they're brighter than plasmas. Some LCD panels have adjustable backlights that let you vary the light output, but not all do. Regardless, they are capable of tremendous, blinding light. In a dark room, a really bright display can be very fatiguing. Often, if the LCD doesn't have an adjustable backlight, adjusting the contrast control won't make the display very dark. Worse, turning down the brightness control further (assuming you have it set correctly) also won't make the display any darker. So reducing the contrast control just reduces your contrast ratio. Besides the fatigue, a high black level is far more noticeable in a dark room than in a well-lit one.

So, generally speaking, if you watch TV more at night or in a dark room, plasma is a better choice. If you watch a lot of TV during the day, then LCD is the better choice.

Lies, Lies, Lies (Not Just a GN'R Album)
In an attempt to sway more buyers to the technology that they manufacture, each side of the flat-panel war has put a lot of misinformation out there. Add in the lack of training and knowledge on the sales side, and this makes for a lot of deception (both intentional and unintentional, which is just as bad). So let's see if we can straighten out some of these misconceptions.

Like I mentioned above, burn-in occurs when a plasma phosphor continues to glow after it has been told not to. With normal viewing, and if you don't turn the contrast control all the way up, it's doubtful that burn-in will be a problem. Also, at least one manufacturer has found that burn-in is significantly less likely to occur after 100 or so hours of usage. LCDs don't burn in. They can exhibit something called persistence, where pixels get "stuck." This may look similar to burn-in, but it's reversible and not common.

Life Span
This is one that each side likes to throw at the other. A plasma display is often rated with a half-life—the time until it's half as bright as it was when it was new. Half-life is typically about 60,000 hours. Your plasma will still be perfectly watchable after this time; it just won't be as bright. This is a gradual process, so gradual that you probably won't even notice it's happening. LCDs, on the other hand, have a life span of about 60,000 hours, after which you will need to replace the backlight. This is not like changing a light bulb, and you can't do it yourself. Even if you think you'd do this after 60,000 hours, it's doubtful that it would be cost-effective. Say you average six hours of TV watching a day, every day. That means you won't reach 60,000 hours for about 27 years. Think of the TV you had 27 years ago. I'd bet money that, in five years, whatever you buy now will be half as expensive and twice as good. Never mind in 10 years. In other words, either type of flat-panel display should last just fine.

Viewing Angle
LCD manufacturers like to claim wide viewing-angle numbers, most of which are bunk. While you can certainly view an LCD from the claimed angles, it won't look as good as it does when you are right in front of the screen. The contrast ratio goes down, the black level goes up (and often changes color), and colors desaturate. The severity of this effect varies with make and model, although it has gotten a lot better over the years. If you have a wide couch or seats off to an angle (any angle, including up and down), check in a store to see if this is going to be a problem for you.

Power Consumption
This is a tough one. LCDs have a steady backlight, which draws the same amount of power regardless of what's on the screen. The liquid crystals require very little power. Plasma power consumption varies depending on what's on the screen. So, with a dark movie, a plasma could draw less power than an LCD, whereas, on a football game, it would probably draw more. Also, if you turn down the contrast control (yes, that again), a plasma will draw less power, although it still may draw more than an LCD. If an LCD has an adjustable backlight, turning that down should also help. If power consumption is a concern for you, again, figure out what you'll be using the display for.

How Are You Going to. . . Never Mind
Hopefully, this has cleared up some of the misinformation that's out there. Not to sound like a broken record (record. . .record. . .), but the key to smart buying really is how you're going to use the display. With that in mind, you can focus on what it is you're really looking for in each technology. What follows are reviews of two 42-inch flat-panel displays from LG Electronics: one plasma and one LCD. For such seemingly similar displays, they perform pretty differently. Their processing performance and a few other things, however, were nearly identical.

LCDs are dropping very quickly in price. A little more than a year ago, a 42-inch LCD cost close to $10,000. While LCD still commands a premium over plasma, that difference is shrinking.

The story here is light output. At 142 foot-lamberts, we've only measured one LCD that was brighter than the 42LP1D, and it was 10 inches smaller diagonally. For that matter, we've only reviewed a handful of displays that were brighter, period. (I've exhausted my supply of clever extreme-light-output jokes, so feel free to insert your favorite here.) This, and the fact that the LCD screen does a great job of muting room reflections, means that this display will do a great job in a well-lit room. The image really pops off the screen.

In terms of black level, the 42LP1D is no slouch, either, measuring 0.147 ft-L. This is just a bit higher than average for the LCDs we've measured. But, thanks to one of the highest light outputs, the 42LP1D's 966:1 full-on/full-off contrast ratio is the highest of any flat-panel display we've measured. For an LCD to take this crown is a real achievement. But, when you compare it with a plasma with a good black level (the 42PX4D, for example), the 42LP1D's black level is noticeably high. Using this LCD, the opening of Master and Commander doesn't look terribly filmlike, with a dark gray filling in as the best black level.

The viewing angle is about average for an LCD from left to right, but the up-and-down viewing angle isn't great. I wouldn't plan on mounting this display above your fireplace.

The 42LP1D is pricier than its plasma brother here, but you get a much nicer aesthetic. The black-gloss front looks very fancy. The silver tube running along the bottom is strange, but it looks nice.

LG 42PX4D Plasma HDTV
It's inevitable that prices come down over time, but it's even more interesting to watch the decrease in black level and the increase in light output. Achieving both without compromising other factors is no small feat. Just a year ago, plasmas' contrast ratios were only a few hundred. Now several plasmas, like the 42PX4D, are close to 1,000:1.

The first thing you notice about this display is its black level. At 0.027 ft-L, it ties with the 42-inch Panasonic TH-42PX25 plasma HDTV from our November 2004 issue (the second best we've ever measured). The only plasma that measured better was the 42-inch Panasonic TH-42PD25 plasma from the February 2005 Face Off, at 0.023 ft-L. That's dark. It's not quite blend-into-the-background dark, but, compared with most flat panels, it's excellent. With the LG 42PX4D, during dark scenes, like the opening of Master and Commander, shadows were actually black. Not CRT black, mind you, but great for a flat panel.

What came as a shock, though, was the amount of light that the 42PX4D puts out. The Panasonic from the Face Off put out 18.64 ft-L from a full-white field. The 42PX34D puts out 25.38 ft-L. That's enough to give it the best contrast ratio of any plasma we've measured: 938:1. With a white window, the 42PX4D is more of a screamer, putting out 71.86 ft-L. This combo of black level and light output is impressive and shows a real effort on LG's part to—oh, I don't know—take over the world?

Unfortunately, there are some negatives. Color is one. The color points, as you can see in the measurements box, are pretty far off the SMPTE spec. With video material, this comes across as an abundance of color, and turning down the color control only partially alleviates the problem. As far as color goes, it's one of the least accurate displays we've measured in recent years. That's not to say that it looks cartoonish. It's not that bad, but it certainly isn't as accurate as some plasmas (or its LCD brother here). For example, grass has a little more blue in it than with other displays.

Noise, both visible and audible, is another issue. Sitting at a normal viewing distance, you can't hear it; but get closer, and you can hear it hum. Most plasmas do this to some extent; it's just something to keep in mind. Video noise, on the other hand, was more noticeable. With most video, there was a fair amount of noise. Darker scenes, such as the opening of Master and Commander, appeared fairly grainy. Turning down the sharpness control reduced the graininess somewhat, but at the expense of detail. There was also a fair amount of noise in gradations from light to dark. While there were some steps in the gradations, they were barely noticeable on test patterns or video.

Phosphor lag, or the precursor to burn-in, is much improved over the LG RU-42PX11 plasma that was in the February 2005 Face Off. It hasn't been completely vanquished, though, and there are a few electronic settings to help prevent it from happening. An orbiter moves the image around the screen very slightly. A white wash puts up a white field to help burn the screen uniformly ("washing" off the burn-in), and inversion inverts the colors of the image. This one is, shall we say, trippy.

Aesthetically, the 42PX4D is pretty normal, with a black bezel around the screen that is a little too shiny. It has a bevy of input and output options, yet another aspect that belies this display's price. Price-wise, the 42PX4D isn't cheap, but it's not too far above the normal range.

Video processing is a mixed bag with these two LG displays. With the Snell & Wilcox Zone Plate test pattern, neither display seemed to pick up the 3:2 sequence. With actual video material, though, it picked it up fairly quickly. Video processing, using the waving flag from Video Essentials, is only OK. There are some jagged edges, although they are small. Both displays scale very well. LG's XD engine, which we lauded in the aforementioned Face Off, doesn't disappoint here. It scales DVDs extremely well, showing an excellent level of detail. Overall, both displays show excellent detail with HD and DVD. With some program material, the LCD seemed slightly sharper, but, with other material (especially that with lots of fast motion), it was a wash.

Both sets have built-in tuners and come with TV Guide On Screen. The tuners do a decent job of pulling in stations and picked up all of the Los Angeles DTV channels with just a small indoor antenna. Keep in mind that our studio location picks up DTV with ease, so your reception may vary. Channel switching is reasonably fast, and deleting all of those crappy SD channels is easy. A cool feature that both displays have is evident when you start picking a station directly, say by pressing "2": It shows a drop-down menu of all the stations that have been scanned that start with "2." If you then dial in "28," the menu will then show "28-1," "28-2," and so on so you can select that station and go to it directly. It may not seem like much of a time saver, but it actually is.

The remotes are laid out the same, but the LCD remote is far more classy, with a black-gloss finish that matches the display. The power, mode, volume, and channel buttons are backlit by a cool-looking white light that you can activate (and deactivate!) by a button on the side. It's amazing, the things we get excited about, eh? On the plasma remote, only the mode button is backlit. Both remotes have a panel that hides the buttons for secondary functions like aspect-ratio adjustment, PIP, and so on. Overall, both are laid out well and fit comfortably in the hand.

Both displays have a front-panel function that shows you which input you're on, and both have aspect-ratio control for all resolutions. Lastly, if you're an ISF calibrator (or if you're planning to get your set calibrated), LG Electronics created a hidden menu to make your life easier by making the sets easier to calibrate. Its implementation is terrific, and no, I won't give you the codes to get into it.

Pick Your Weapon
The LCD offers the best contrast ratio, but its black level isn't good enough for hard-core theater duties. The plasma is bright and has an impressive black level, but its penchant for phosphor lag prevents me from recommending that people run it flat out in a well-lit living room. Side by side, the differences are subtle. With bright program material, the LCD is the eye-catcher, with slightly less noise, slightly more resolution, and more natural color. (Did I mention that it's also bright?) As soon as there's black on the screen, the plasma takes the lead. There is no substitute for a good black level, and it draws your eye right away.

So there you have it, two good examples of what LCD and plasma can offer. It all just boils down to that final question: How are you going to use it?

• Very bright
• Impressive contrast ratio

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