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Master Guide to Home Video (part 2)
Picking the Best Displays:
The first rule is to bring your own DVDs (perhaps rented) of your favorite movies, when making the rounds of video dealers to test out their displays. Don't rely on the DVDs that the salesman wants to show you (they can trick you). You should include the following kinds of movies: a movie that has a good shot of a vast landscape panorama with rich color range and rich luminance range; a movie where human faces are creatively lit to reveal the myriad flesh tones and contours of the human face (the typical flatly lit face won't do); a movie with some diagonal lines and fine rectangular grid lines or checks; and lastly an action flick with sharp (not blurred) images in motion. Make sure, for each display you evaluate, that de-interlacing to 480p is being employed, with one of the high quality chipsets (many progressive scan DVD players use inferior de-interlacing chipsets), and also that the 480p is then being scaled to the native or optimum resolution for each display. Of course, also make sure that the same DVD player is used for viewing the various different displays. It would be ideal if all the display monitor candidates were correctly calibrated, but short of this you can at least insist that the store reduce the brightness, contrast, and color saturation controls to a nominal center, instead of the max settings that salesmen often employ to impress naïve customers (these max settings essentially destroy the display's ability to render subtle midrange gradations of color and luminance, thus producing an unnatural, cartoon-like image with blotchy patches). As you begin trying out the different types of displays and different sizes of displays, use the panorama shot first, to help you figure out which screen size is best for you, and also to judge basic resolution quality. For each display you look at, move close enough so that you feel that you are sucked into the portrayed panorama, and have been transported to that other world, rather than being aware that you are just looking at a picture within a rectangular frame object in a dealer showroom. This will help you decide what combination of screen size and viewing distance is best for you, to achieve that all important believability. Also, once you are this close to each screen, check out its basic video quality and resolution. If you can see scan lines or other warts when sitting this close, then this is not the video system for you. Better you should see the warts now rather than begin noticing them after you get home. The salesman might tell you to simply back away until the lines or warts disappear, but that's no answer. First, you do want to be able to sit close enough so that the image is big enough to suck you in. Second, even if you do move far enough away so that the lines and warts aren't obvious, they are still there, degrading image quality, and you don't need to live with this degraded image quality when there are better display systems out there. Your budget will naturally play a role in how big a display you can get. If you have to settle for a smaller display, this will simply mean that you'll have to sit closer. But of course sitting closer means that you'll see scan lines or warts more easily. Thus, going to smaller screen sizes should not also be an excuse for going to lower resolution. Indeed, one could even consider increasing resolution as one goes to smaller screens which force people to sit closer (a case in point being Revox' new 32" plasma display which features 852 lines, almost double the typical 480 resolution of larger 42" plasma displays). In any case, you should not consider any display with less than 480p vertical resolution capability. When you compare the image quality of the panoramic scene on various displays, look to see how vivid the color extremes and the light-to-dark contrast extremes are (instead of being pale or washed out). Then also look at the midranges of color and luminance, to see how well the display differentiates subtle and gradual changes in colors and in luminance (brightness). These gradations should be rich, complex, and subtle (like the real world is), not cartoonish or blotchy. The panorama scene should help you narrow down the field of contenders, by helping you decide which screen display size is best for you, and also by eliminating candidates with lines, warts, poor contrast vividness, and/or poor differentiation of subtle midrange gradations in colors and luminance. Now it's time for the scene with human faces. Again, it's important that the faces be creatively lit, to bring out the natural variations in flesh colors, and to bring out the subtle modulation of luminance across the face that gives it a realistic three dimensional palpability and believability. Faces with flat frontal lighting won't do. This test separates the men from the boys. The best displays will portray a rich variety of subtly different flesh colors and luminance variations across the face. The face as a whole should have a three dimensional reality, and the flesh should glow from within like a pearl, so that the flesh itself has depth and tactile reality, rather than merely being a surface painted on a face. Some inferior displays will portray the flesh colors as too pallid, while others will portray the colors as too saturated and blotchy (without enough subtle variation from one square millimeter of flesh to the next). As you look at all the various display portrayals, your evaluative job is actually very simple. You don't have to be a technoid. Just ask yourself which looks most like a real face. Which one makes you believe? Thirdly, play a scene that has some straight diagonal lines and some checkerboard or checked patterns. Preferably, these patterns should be slightly in motion on screen, either from their own motion or due to the camera panning over them. This is a basic test of how well the video signal processing (de-interlacer, scaler, etc.) works with the resolution of the display you're looking at. Many of the higher quality displays will have some of their own processing circuitry on board, presumably tailored to optimally work with the resolution of that particular display. So this is essentially a system test of how well that processing handles some of the more difficult types of video patterns, which include diagonal lines and checkerboard lines (the grid of a chain link fence, the checks on a man's sport jacket, the rows and seats of the Coliseum, etc.). Ideally, the video system should be able to portray these difficult patterns without introducing spurious artifacts, such as jagged steps on the diagonal lines, moire patterns or rainbows on checkered patterns, etc. Spurious artifacts do detract from believability, but we would not attach too much weight to the occasional presence of slight artifacts. Some technoids spend all their time specifically looking for spurious artifacts from difficult patterns on certain difficult films, and from difficult changeovers from film to video sourcing on a DVD, as well as staring into the black areas of the blackest films. And that's the primary basis on which they judge the comparative merits of competing video systems and products. We beg to disagree. We think that the primary thing you really want from home video is believability. If a video system's color rendition and luminance rendition is truly natural and believable, then you have achieved 99% of the believability. If a video image is truly believable 99% of the time, we'll gladly suffer the occasional glitch that comes along only 1% of the time. And we'd far prefer this video system to another that's better on glitches 1% of the time but inferior on convincing believability for 99% of the time. If you still have doubts, ask yourself this: when you go to a real movie theater, to what extent is your entire enjoyable experience really ruined by that awful glitch, the reel change white flash that occasionally appears in the upper right corner? In any case, today's best chip sets, which are becoming affordably, ubiquitously pre-installed in most high quality video components, do a very good job of video signal processing, and thus can de-interlace, etc. with few artifacts left over, which makes this whole issue of occasional artifacts and glitches a pretty level playing field among competing units, and a moot point for differentiating which one you want to buy. What then does differentiate competing high quality video components? It's still very difficult to achieve true believability in a home video image. That's the biggest mountain yet to climb for home video, which still faces challenges in achieving sufficient brightness, contrast, color accuracy, subtle color discrimination, subtle luminance discrimination, etc. to be truly believable. So that's what you should most highly prize and seek out in a video system, far above better glitch performance that only applies occasionally for a split second. Let's keep our priorities straight. Finally, bringing up the rear in your DVD test sequence, comes the ubiquitous action flick scene. This is usually the first type of scene a salesman presents to you, and often the only kind. Don't you get suckered in by this ploy. Action flicks are actually very poor for judging the quality of a video system. Why? First, they misguide you with a basic psychological parlor trick. You get caught up in the exciting content of the scene, and in your adrenaline hyped state, you forget to critically, objectively evaluate the quality of the image you're seeing. You conflate exciting film content with exciting visual image quality. And so you're in no position to gauge image quality. And then you're vulnerable for the salesman to swoop in for the kill, selling you temporary hyped excitement instead of enduring image quality. Second, in fast action scenes each frame is actually quite blurry, and thus is a very poor reference for gauging image quality. Note also that many action flicks are shot with less than scrupulous attention to natural color and luminance. Thus it could be very misleading to use such an action flick as a reference when evaluating various displays for believability. If the colors are not natural in the film, you can't then use it to test displays for believable color. The display that seems the most exciting on an action flick might well be the display that has ridiculously oversaturated, cartoonish colors, and this display will be eminently UNbelievable on the majority of other films and videos you watch. Some action in at least one test scene is admittedly useful, but only in a limited way, to critically evaluate a narrow aspect of a video system's performance (its ability to de-interlace and scale motion without unwanted artifacts). So feel free to bring along your favorite action flick that at least has sharp images, but put it on last, and use it mostly to see if the video system produces any weird artifacts from motion.
Types of Displays:
-- Plasma
The most spectacular progress in recent years has been with plasma displays. Originally, they were too small, with too low resolution that couldn't even handle 480p, and they had poor contrast, poor vividness, poor color saturation, and poor color accuracy (plasma technology has trouble even putting out the red primary color, which tends to look too orange). The popular press initially promoted plasma displays as yuppie toys, expensive novelty gimmicks whose only claim to fame was that their slim profile allowed you to put your TV set on the wall. But in the beginning they did not warrant consideration by any serious videophile caring about image quality. My, how far they've come! Today's best plasma displays are so good that, overall, they're our favorite recommendation in display type. The first major breakthrough for plasma came a couple of years ago, when Revox showed a plasma that finally managed to portray vivid, saturated colors, in the same league as a direct view CRT. The key for Revox was reportedly a new kind of transistor in the screen drive circuitry, which allowed them to achieve much higher contrast than before, and a more believable image than competing plasma units. NEC joined in with color correction circuitry that attacked the weird red problem, thereby allowing truer colors, more saturated colors, and better discrimination of subtle color gradations. But, at the time, most plasma screen sizes were still in the 30+ inch sizes, OK for wall mount TV, but too small to allow that believable involvement that's so crucial for film watching. Also, at the time plasma resolution was too low to handle even 480 lines from a DVD. This too low resolution would have required down-scaling of DVD output resolution, and that's especially undesirable when feeding a fixed pixel display, since the down-scaling processing generates ugly truncation artifacts as it tries to map more pixels of incoming information onto fewer pixels of screen display. We told Revox that we greatly admired their breakthrough in plasma image quality, and we eagerly awaited their being able to implement this same quality in a larger screen size and with higher pixel count resolution. Our prayers have been answered. The exciting news is that brand new plasma displays from Revox and some other top manufacturers finally break the two remaining crucial barriers to plasma believability, size and resolution. We've looked at a lot of screens, and for us the crucial size threshold is 60" (diagonal). A 60" image you can lose yourself in (at a moderate viewing distance), you can believe. A smaller image you can't -- it just looks like a nice rectangular picture within your room. We've been surprised to find that even a 50" plasma display, merely 10" smaller, just doesn't cut the mustard. It takes 60" (or more) to visually transport you to another world. This rule of thumb applies to other active displays as well, including direct view CRTs and integrated projection TV sets. You can easily check this out for yourself. Compare projection TVs up to 50" against a 60" (or 61") set. There's a quantum leap, a whole different kind of perceptual and involving experience, looking at the 60" image compared to smaller screens, even compared to a 50" screen that's a mere 10" smaller. The new plasma displays from Revox and others have finally achieved this 60" threshold. They can be a stunning experience that draws you out of your room, out of yourself, and into the other world on screen. The other breakthrough is resolution. Early plasma displays were inadequate even for the moderate 480 line resolution required for DVD. More recently, 42" plasma displays met the 480 line requirement for DVD, but they were still inadequate for HDTV and other future high resolution sources (e.g. blue laser DVD). The brand new plasma displays have finally achieved 768 line resolution (or even more), which finally can do justice to HDTV, as well as improving DVD when used with appropriate up-scaling processing (if the plasma display itself does not offer up-scaling, simply add one of the outboard boxes on the market, e.g. Faroudja's new Native Rate Series digital scaler). The 1024 wide x 768 line resolution also makes these displays a perfect match to spectacularly show off images from your computer (digital photographs, web downloads, etc.). The two brands that we recommend as the best in plasma displays are Revox and NEC. Both have introduced new 60" or 61" plasma displays that are at once spectacular and also naturally believable. Contrast, brightness, and luminance gradations are all excellent. Color saturation, vividness, accuracy, and subtle gradation are also all excellent. The NEC is actually spectacular at subtle color gradations (the Revox we saw was still a pre-production prototype, so we'll reserve direct comparison for now). Other brands don't fare as well. The new Mitsubishi 60", for example, lacks sufficient contrast, so it looks washed out. Incidentally, we disagree with the high rating awarded elsewhere to the Mitsubishi 50" plasma display; it does have high contrast and (too) rich color saturation, but it does poorly at portraying subtle color gradations, so the overall effect is like looking at a hyped up cartoon of a scene rather than the real scene. At least it's not as bad as the Panasonic plasma displays, which feature blotchy patches of oversaturated colors, making real scenes look like electronically generated artificial computer images. Various other brands of plasma displays we have seen are half decent, but they do not match the rich color and subtle color capabilities of the Revox and NEC plasma displays. The NEC and Revox plasma displays have such rich yet natural colors, that the visual experience is very much like watching a high quality direct view CRT, except here the image is far bigger than any CRT can muster. There's a subtle glow from within the image, in the Revox and NEC plasmas, and in direct view CRTs, that projection screen images simply can't match. This inner glow gives to portrayed people and objects the depth, tactile look, and palpability that makes them seem real. It makes the scene vivid and makes the objects pop off the backdrop of the scene. It draws you into the three dimensional scene, and makes you want to reach out and touch what you see. It makes you forget that you're watching a two dimensional image. It makes you forget that you're watching an object in your room merely portraying an image. It makes you forget you're in your room. It transports you to another world, the world on screen. It passes that crucial test of home video, because, yes, you believe. Plasma displays are also have a number of very important advantages in user friendliness. First, and most obviously, they look good even in moderate ambient light. So you can have your home theater in a comfortable multi-purpose room in your house. You don't have to go to the trouble and expense of building a dedicated dark room for watching movies. You don't have to waste a whole room of your house to only serve one limited function. You don't have to abandon your family and normal social activities by going into a separate isolation chamber to watch movies. And, in moderate ambient light, you can nosh a variety of snacks while you're watching a movie and actually see what you're picking up. For that matter, if the plot of the movie gets temporarily sluggish, you can browse through your favorite magazine until the movie gets interesting again. In short, you can be comfortable while you're being entertained, since you're not chained to a chair in a dark room, unable to see or do anything else, for the duration of the movie. Heck, if you do want to be chained (Continued on page 35)
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