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If I were allowed only one plasma screen, the NEC 61MP1 is the one I'd take. With a 61-inch diagonal screen which makes for about 1,591 square inches of viewing pleasure—NEC has finally produced a plasma big enough for me. What can I say? I like big screens so I really like the size of the NEC's screen, but the weight (134.5 pounds) along with plasma's reputation for fragility is kind of scary for such a wide and perhaps easily tipped over unit. If God grants me my wish and a 61-inch plasma falls off a truck in front of me without breaking, I'll pay extra for a very careful installation crew to mount the thing permanently, up high on the strongest wall I've got. Just the thought of some kid falling against one resting on its skinny 17-inch wide tabletop stand makes me cringe. Okay, enough of that—once it's set up, the biggest plasma on the block produces light, like all the other smaller ones— by electrically exciting a gas surrounded by light-emitting red, green, and blue phosphors. The gas is trapped between two large (and heavy and very thick) pieces of glass that have had tiny phosphor-coated pixel chambers (about a thousand times smaller than the glass thickness) etched and trapped between the glass plates. The basic excitation mechanism is like the process used in a fluorescent lamp, since the plasma display's excited gas emits UV radiation that then excites the colored phosphors. The plasma display's image is therefore composed of light that makes its way out of each pixel's tiny glowing chamber buried between the thick glass plates. The relative difference in size between the glass plates and the lighted gas chamber contributes to some of the lack of electrical efficiency and brightness for plasmas, in general—well, that and the fact that you can only pump in so much power before even heavy glass cracks. Anyway, the pixel chambers are separated from each other by ridges that hold the two pieces of glass a fixed distance apart. In the early plasma displays, the supporting and separating ridges pixels were much wider and gave early plasma's image a broken, stripped appearance. Modern plasmas like NEC's 61-inch use thin ridges that have little impact on the image. However, the pixel gaps still appear to be a couple times larger than what you can see in a similarly-sized CRT or LCD projector. And the pixels and gaps in the 61-inch plasma are larger than those on NEC's 50-inch unit, as well. This is because NEC essentially just enlarged and transferred the 50-inch XGA resolution plasma design to a larger piece of glass. Everything else is about the same for the 61-inch as for the 50-inch—with the exception of needing more power to light up the much bigger display. up against the wall Bigger is right—when I first saw it, I couldn't stop staring. The 61-inch plasma's screen area is more than two times the area in a 42-inch plasma and it's still about 1.5 times as large as a 50-inch plasma. But that size comes at a price—and I don't mean in dollars—the 61-inch plasma can be had for about the same price as what 50-inch units sold a little while back. Plasma prices have been dropping almost as fast as their popularity and sizes have been increasing. No, the price you'll really pay is in size, weight, and power consumption. The 61-inch plasma takes up over twice the 3D space as the 42-inch units since besides having a larger screen area, the 61-inch is a lot thicker too: it's close to five inches thick. And that space is filled with heavy stuff which makes the 61-inch unit about twice the weight of the 42-inch plasma. Like I said before, I cringe at the sight of a 134.5-pound behemoth being balanced on a slender tabletop stand. I want mine mounted on a wall—but it has to be a sturdy wall. You can't just drive a few nails in the plaster for this baby. Get a construction crew and some unionized iron workers involved, too. not easy being green While you're at it, make sure that your electrical mains are as well-braced as your walls have to be. Where the best, most efficient 42-inch plasma made its light using a bit less than 300 watts of electrical power, this 61-incher from NEC takes over 600 watts. That's a lot of power, but it's way less than what was first reported by some other folks who first showed me a 60-inch plasma several years ago. That big unit never made it into production; good thing, too, since they used to talk about needing over 1,000 watts. The NEC's 600-watt requirement is still a lot, but as long as there's a pristine wilderness left to drill and despoil, the boys in power will likely keep the juices flowing to the all the households that want to crank up their conspicuous consumption. Just for comparison's sake, a Greenpeace-approved 27-inch TV set from Sony that can run all day without whimpering only sips about 100 watts of electricity max—even less if you run those poorly-lit daytime shows. Plus, if you use your Apple Cinema Display LCD monitor for a TV, you can cut that 100 watts in half and that sounds very green, but it's not a 61-inch screen! inch by inch, row by row Spec'ing a plasma's light output is another kind of tricky deal. Unlike a projector that uses a steadily shining lamp, the amount of light produced by a plasma changes by how much of the screen area is being lit up, which is why it takes me such a long time to make all the measurements. When only a small, 10% of the total area piece of glass is shining, I measured a relatively impressive 218 nits or candelas per meter on NEC's 61-inch unit. That amount of "peak" brightness is actually a little more than what I found on one of NEC's 42-inch plasmas a while back, although the brightest 42-inch plasmas from others can make more than 250 peak nits in a small area these days. Small-area brightness provides punch to the viewing experience, but that punch was quickly reduced on the 61-inch plasma when more screen area was involved. I measured 101.59 nits on average over the 9-ANSI measuring points using the row-by-row method that I've always used with plasmas and CRTs. The row-by-row method results in a 33% average picture level (APL) because at any one time, only one-third of the image is white while the other two-thirds are black. When I measured the brightness with the full screen on, all white, all the time, the measured light output dropped down to a miserly 43.56 nits. For comparison purposes, the previously measured 42-inch set from NEC made about 207 nits at 10% area, 167 nits with 33% of the screen involved, 128 nits at 50%, but still 76 nits with the whole screen working. This kind of variation in the light output versus APL is typical of systems that use what I call "limiting" power supplies. The manufacturers do not want to let the screen get too hot or over stress so the power supplies are prevented from putting out all the power they need to light up a full screen to maximum brightness. With the NEC plasma I tested, the power supplies max'd out at 624 watts—the highest I have seen to date, but still below the 660 watts maximum that NEC specs for this display. Unlike plasmas, LCD monitors, like Apple's big Cinema Display, as well as projectors (whether LCD or DLP), put out the same level of on-screen brightness regardless of how much or how little screen area is being lit. But no one makes a 60-inch LCD monitor, and so in spite of its brightness variation, I thought that NEC's 61-inch plasma was bright enough—especially since most DVD movies barely require 33% APL and that low level allows for a lot of contrast with the smaller and sufficiently brighter patches—like the headlights chasing a victim in a cop movie. Besides you only notice how dim this plasma is (and all plasmas are dim under similar conditions) if a full white, max power screen is demanded, and who does that? Well, hooking up your PC and showing a bright desktop or surfing the Web will crank up the APL and pull those plasma power supplies down to a noticeable point, but once you start running DVDs again, which have relatively low APLs, you'll forget all about those problems. contrasting apples to apples I sometimes talk about electrical efficiency when I review projectors. With a projector, it is easy to find the overall efficiency, I just divide the measured ANSI lumens by the projector's lamp's rated power in watts. This gives me "lumens per watt" and the best units regularly exceed 10 or more lumens per watt—which is why so many projectors can make 2000 lumens or so with a tiny 150-watt lamp. Plasma brightness is not measured in lumens, but in nits, which means candelas per square meter. You cannot just divide nits by the power consumption in watts because nits include area unlike lumens. Anyway, to find efficiency of a plasma, I first take the 33% APL "nits" and then divide by the power consumption. The results show that the NEC 42-inch plasma is the most efficient at 0.512 candelas per watt and that the NEC 61-inch is the least efficient at only 0.182 candelas per watt—however, since the 42-inch set is a lot smaller in area, its total efficiency is actually much closer to the 61-inch unit's. Since its viewing area is roughly a square meter, you can very roughly multiply the 61-incher's candela per watt values by three to get close to an approximation of its lumens rating. For example, with a 33% APL, 101 nits is close to 327 lumens. Dividing those 327 lumens by the 557 watts required to make the light gives you an apples-to-apples comparison with a projector's lumens-per-watt reading—all of which shows how horribly inefficient plasmas are in comparison to projectors. Anyway, I measured the big NEC's ANSI 16-point contrast ratio at 110.37:1. That's a bit less than the smaller NEC units and a lot less than the contrast-producing champions from Panasonic. NEC needs some help in this regard because their black levels are rather bright—too bad they can't use Panasonic's patented contrast-increasing methods. The 61-incher could use more contrast, but its 110:1 contrast ratio doesn't totally spoil things the way the first plasmas' 50:1 or less ratio did. number by colors I also measured the corner brightness of the NEC and found it to about the same (99.28%) as the center brightness on average—which is similar to most other modern plasmas. In terms of contrast, brightness, evenness, corner brightness, and viewing angle, the NEC 61-inch plasma performs about average—but what it has over the herd is size. And size matters, but so does color, and like all plasmas, the NEC unit's colors looked a little different from those seen in most LCD projectors and on CRTs. NEC's plasma produces color by exciting a gas to produce UV radiation that further excites a colored phosphor—different phosphors than those used in today's video- and color-standard machines, high-voltage CRTs. However, instead of relying completely upon the colored light produced by excited phosphors, NEC has placed tiny color filters over each pixel in their plasma. These color filters are similar to those used in large LCD monitors like Apple's, but they operate a little differently. Where the color filters in an LCD monitor change the backlight's white light into colored light, the color filters in the NEC plasma just "purify" the already-colored light emission colors to bring those colors closer to SMPTE standards. This filtering reduces the overall brightness a little (10 to 20% according to NEC's engineers), but that filtering improves the colors. I measured 17.20 units of color saturation with the NEC plasma, which is a lot more than the 16 or so generally seen with LCD projectors—and a lot less than the 21 or so color units that most humans can perceive. SMPTE color standards only require about 15 or so color units. Therefore, any extra saturation above that level needs to be "adjusted down" to get "true" colors. However, I think it's better to have too much color than too little, since you can't put any back with the remote control. However, in spite of the large measured values, the NEC's colors were not balanced. The red colors were about right; the blues were close, but a bit weak; and the greens were way off and too highly saturated. I found that even with the over-saturated greens, the white point was still close to true white (which is an improvement improved over the older 42-inch unit) with only a 2.25 color unit error. 61* Overall, NEC has improved its colors a bit, improved its white point, and reduced the green saturation in comparison to its 42-inch unit. But the 61-incher's greens are still more overly saturated than anyone else's products. The colors still don't hit the SMPTE marks unless you turn the greens down a lot—but then, if properly adjusted, the NEC's colors can look pretty good. I've said it before, but if only NEC would crank its power supplies up a bit more—use even more power—and then cut back on the green saturation some while allowing just a little more blue... Well, I suppose that they've already had that discussion and who really wants to burn up more watts besides the guys that sell them? But with just slightly better color balance, I think that the NEC plasma could compete quite well with any large-screen system in terms of basic image quality. Besides having good video, the NEC plasma also performed quite well with a computer data input in XGA resolution—and that's something no TV monitor can do easily or as well. Plus the NEC unit can actually take even higher-resolution signals—up to UXGA, according to their spec. But I don't think that plasmas do image compression very well; their resized images get noisy from the required dithering-based resizing modulations. The 61-inch plasma has good video since one additional area that NEC improved with this set over previous units is in the video processing circuits. NEC has improved their circuits and added some work to the processing that compensates for the miss-match in frame rates between film and video. This processing—called 3-2 pull-down for the method of matching 24 frames per second to 30 frames per second—takes away a lot of the noise sometimes seen in fast-moving, action-packed DVD movies. You can see some improvement over earlier sets; however, I think that you can also still see some "motion smearing" that results from the slowly responding plasma struggling to keep up with its grayscale algorithm in the face of all that rapid motion on those action-packed DVDs. Oh well, I guess there are still some tradeoffs involved in conspicuous consumption: good, but imperfect video, too much green saturation, and too little contrast too. As I described earlier, when the big plasma's screen fades to black, it doesn't get black enough. But don't get me wrong, I still want a 61-inch plasma, and if I get one, I promise only to use it to watch quality movies. That way, the lights in the house down the coast won't dim if I only occasionally turn up my power consumption.
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