Monday, June 12, 2006

My Bedroom: Crying Out for HDTV?

I've been putting off getting a new TV for the master bedroom of my house. Having sold my long-in-the-tooth Sony Trinitron XBR 27" CRT last year to make way for one, I have space for a set that is between 42" and 50" diagonally ... but what TV should I get?

I'd prefer a flat panel with a small footprint, made even smaller by possibly wall mounting it. A rear projector would likely occupy the entire top of its stand, front to back, leaving little room for home-theater speakers. My bedroom doesn't offer a lot of alternative front speaker positions other than right on the same stand (or, again, wall mounts).

Assuming I'm looking for a flat-panel TV and not a rear projector, I figure the model to beat could be the Pioneer Elite PRO-1130HD 50" plasma. Despite its hefty list price, $5,500, Randy Tomlinson's review in the March/April 2006 The Perfect Vision glows with admiration for it. Tomilinson says, "All things considered (except price), I haven't been more impressed with any plasma TV ... ."

There is also a 43" in the same line, the Elite PRO-930HD (MSRP $4,500). I'd prefer the larger, but might settle for the smaller to save $1,000.

Pioneer builds into these models such things as a "Crystal Emissive Layer," which, according to this online article, is "sandwiched between the plasma glass and individual light cells to increase the speed at which each cell is charged and discharged, resulting in better blacks with more details in dark scenes as well as an overall reduction in energy consumption."

For most plasmas — with the apparent exception of those from Panasonic and now Pioneer — the depth of blacks and the adequacy of shadow detail has always been Achilles' heel number one. But Tomlinson writes, "This Pioneer's black level passed the home-theater [i.e., totally unlit room] test as well as any other current plasma — Panasonic included. Blacks were about 75% lower than the 55-inch Hitachi [the very good plasma TV being used as a reference system]."

As for color renditions, these Pioneer Elite is virtually bang-on the HDTV standard's chromaticity specs for red, green, and blue primaries. That's when using PURE mode, one of five user-adjustable presets, others of which include STANDARD, GAME, and MOVIE. (In other preset modes, the PRO-1130HD apparently oversaturates greens and undersaturates reds, according to Tomlinson's review.)

Inaccurate primaries are not at all unusual. What is unusual in this TV is a user-selectable mode that gets the chromaticities right. Apparently plasmas, if they have enough smarts built into them, can overcome the off-standard native hues of their screen phosphors.

One other factor is crucial to getting colors right: a neutral grayscale that puts the "color of white" just where it belongs, at the chromaticity known as D65. D65 is sometimes (slightly erroneously) identified with the D6500 or 6500K "color temperature," but whatever it's called, the accuracy of a TV's white point is important. All colors are in effect computed from four anchor points: the white point and the three primaries. So if the white point is wrong, all the computations are wrong.

Few TVs get D65 right, right out of the box, without professional calibration. The Pioneer Elite gets tolerably close. Tomilinson, for instance, puts its MID-LOW color temperature setting at "about 6300K."

At that setting, he says there is also (alas) a "slightly greenish error." It, I assume, is something like that on my Hitachi 32HDT50 plasma in the basement — see Since When Is Black and White Green? The fact of this slight greenishness illustrates exactly why specifications of "color temperature" don't tell a TV's whole story, grayscale-wise, and chromaticity coordinates should be cited instead. The greenishness doesn't come from the difference between 63ooK and 6500K, as color temperatures per se. It comes from the white point being shifted, whatever its color temperature, away from true D65 and in favor of green.

For every chromaticity has its own "correlated" color temperature. This is, on the so-called "Planckian locus" or "black-body curve," the nearest "white" point to the chromaticity in question.

That curve is the graph of all whites emitted by ideal "black-body radiators" — special metal objects also called "illuminants" — that are heated to various absolute temperatures which are measured in Kelvins or K units. The chromaticity termed D65, though it is not smack on the Planckian locus, is quite close by. Its nearest black-body-curve point has the color temperature 6500K. (Actually, 6504K, but who's counting?)

CIE Chromaticity Diagram
But there are many other chromaticity points that have the same color temperature, and these can look noticeably greenish. For color temperature is a line on the CIE chromaticity graph, not a point. Each such line line crosses the black-body curve at a point which defines the line's color temperature. But the line is not a single chromaticity point. D65 is — as is, say, point D on the diagram to the right. That point is near the 6500K line, so that is its nominal color temperature.

(This diagram furnishes a workable definition for the term "chromaticity." It's any color within or on the edge of the shark-fin-shaped area of the CIE diagram, and it is exactly specified by a pair of coordinates. For example, x= 0.312713 and y=0.329016 are the coordinates of D65.)

The Pioneer Elite's white point at its MID-LOW color temperature setting, accordingly, is apparently shifted slightly away from D65 in the direction of green. But not to worry. This TV has a built-in "ISF C3" calibration capability that apparently lets you adjust the relative contributions of red, green, and blue color primaries to white, at both low and high brightness levels.

This is what professional calibrators, trained by the Imaging Science Foundation ("ISF"), do. They adjust the three primary colors ("C3") to produce whites and grays as close to perfect as can be achieved at every level along the available brightness scale from near-black dark grays on up to near-white light grays, and finally to so-called "reference white." With these Pioneer sets, you can do the calibration yourself!

ISF C3 is a function, I gather, of a particular submenu of the Pioneer's MANUAL color temperature mode — for more, see the technical discussion here, part of Al Griffin's review of the PRO-1130HD for Sound & Vision magazine, online here. Griffin writes: "The Pioneer PRO-1130HD's Mid-Low color-temperature mode measured close to the 6,500-K standard, but the set displayed a mild shift toward green at both ends of its grayscale. I was able to correct this, however, using the high and low red, green, and blue adjustments in the MANUAL color temperature mode submenu without having to enter any special service menus."

"After calibration," Griffin continues, "grayscale tracking was ±100 K from 20 to 100 IRE - an above-average level of performance." Griffin is talking about the IRE scale of brightness that runs from 0 (or sometimes 7.5) IRE for pure black to 100 IRE for reference white. 20 IRE is a very dark gray.

(Yet another useful review of this Pioneer Elite HDTV can be found here.)

Of course, to get the calibration absolutely right, you'd need professional instruments. Still, it's nice to know that you don't have to go into any super-secret "service menu" to play around with seat-of-the-pants calibration efforts, maybe messing up some important settings accidentally and irretrievably.

By the way, the PRO-1130HD also has still other user-adjustable color settings that tweak not only reds, greens, and blues, the three color primaries, but also the three color secondaries — yellows, magentas, and cyans — thereby to render every available hue just the way you want it. That's in addition, of course, to the ordinary color and tint controls.

To be quite frank, I'm not at all sure why taking control over the secondary colors is of great value. In theory, if you have the three primaries and the white reference right, all the other colors should fall right into place.

At any rate, what with spot-on primaries, a user-calibratable grayscale, and all the other user adjustments for color, one ought to get some stunning renditions. Add to that the excellent blacks and dark grays, and a superb picture is truly within reach.

And the renditions are indeed stunning, these reviewers say. Furthermore, the picture is easy to tailor. Griffin liked:

  • the "solid blacks and impressive shadow detail" that allowed the detection of "fine textures and hues in the grandparents' dark earth-toned clothing" on the Charlie and the Chocolate Factory DVD
  • the "very good detail" shown by picture highlights, "with a variety of creamy white tones coming through" to prove that the Pioneer does not "crush" high brighntesses near reference white
  • the Pioneer's "exceptionally clean and rich" colors
  • the TV's "perfectly natural" skin tones
  • its "great job of displaying the high-contrast environment inside a command center" on ABC's 720p broadcast of Alias
  • the fact that "the picture was extremely sharp" on that show
  • the way the Pioneer "cleanly rendered the medium's grainy image texture" on that show, which is shot on film: not "noisy or [with] a coarse quality," but "at once crisp and smooth"
  • the fact that most of the Pioneer's selectable aspect ratio modes, such as 4:3 and Full (16:9), "can be selected for both standard and high-def signals"; a lot of TVs won't let you, say, switch a high-def input's aspect ratio to 4:3 when that's appropriate for the source material
Tomlinson liked:

  • the TV's noise reduction feature (actually, two of them) which helped 480i inputs from a DVD player, and "even digital stations and HD"; the noise reduction, says Tomlinson, "seems to soften the picture almost imperceptibly," unlike that in many other TVs
  • the fact that "the Pioneer was even sharper than the [reference] Hitachi, and yet with less edge enhancement — something I hadn't expected"
  • the fact that "each of the factory-preset modes can be customized, and those custom settings are remembered when you switch modes or input sources"
  • The Pioneer's "remarkable resistance to false contouring" in the "Anglerfish" scene in Finding Nemo
  • though "some dithering noise near black" did show up in Nemo, "dark scenes in Vanilla Sky, which brought on some dreadful artifacts on the Hitachi, were flawless on the Pioneer."

Other features I especially covet on the Pioneer PRO-1130HD include the two digital HDMI inputs (even more would be appreciated) and its separate media receiver, detached from the display panel, to which various source devices' input cables run. That makes it easy to mount the display on the wall, if desired, since the cables between the receiver and the wall-mounted display panel don't change when you, say, hook up a new DVD player.

What I don't like about the PRO-1130HD — in addition to its steep price, that is — is that it's not 1080p. It's screen contains 1,280 pixels across, the same as 720p. Its 768 pixels vertically are just a tad better than 720p resolution. That's good, but not great.

Of course, as Tomlinson points out in his review, "at distances of 12 feet or more, you may not see any difference" between a 720p/768p 50" HDTV and a true 1080p. I'd be almost exactly 12 feet from my display as I prop myself up in bed to ogle it.

Actually, according to a "Tech Talk" piece by David Ranada in the same Feb./Mar. '06 issue of Sound & Vision, "Maxing Out Resolution," if you sit 10 feet or more from a 720p 16:9 display, your eyes are starting to lose picture detail. Or so the graph which Ranada provides suggests.

The article extends Ranada's "The Progressive Tradeoff" discussion of the previous month, which said, "Unless you have fighter-pilot vision — markedly better than the standard 20/20 — your eyes will be able to resolve an object only if it extends over 1/60 of a degree (1 arc-minute) or more, which is what a 1-inch wide object appears like when seen from 100 yards away."

That's 1/60 of a degree at the retina of your eye, or 1/60 of a degree "out there" in your field of view. Any detail which subtends a smaller arc than that will simply not register. So at a viewing distance of just short of 9 feet, "a 50-inch (diagonal) 720-line widescreen HDTV will give you all the resolution you can use."

Yes, there's a minor discrepancy here. One time, the magic distance seems to be 9 feet for 720p; the next time, its 10 feet. But the principle is clear. If you sit too close for the screen's resolution, the image starts to appear soft and it becomes possible to notice individual pixels. If you sit too far away, you effectively leave picture detail behind at your retinas.

According to Ranada's graph, the magic distance for a 50" 1080i/p 16:9 TV is about 6 to 7 feet. Any seating distance beyond that loses effective resolution. Somewhere between 9 and 10 feet, you can no longer tell the difference between 1080i/p and 720p.

Moral: if I put a 50" plasma in my bedroom 12 feet from my accustomed propped-up-in-bed viewing position, it might as well be 720p as 1080p.

Word has it that Pioneer and rival makers are set to introduce true 1080p plasma HDTVs real soon now. In fact, for a cool $10,000, I could buy Pioneer's 50" Elite PRO-FHD1 monitor, "available June 2006," about which I know very little as yet.

I do know that it's not equipped with a digital television tuner, as the PRO1130HD is — which is why it's a "monitor." (I care little about an onboard tuner, since I get my TV signals from cable.) It has the ISF 3C calibration capability, I see.

I assume that as 1080p plasmas come, they'll be even pricier than the PRO-1130HD. (In fact, Pioneer may at that point be forced to drop its price on what will be a last year's model.) I also assume Pioneer's 1080p plasmas will include at least one model with the picture quality and advanced features of the PRO-1130HD, making that model the one to beat in my bedroom-TV search!

What about sound, though? I don't fancy cluttering up my already-cluttered bedroom with a full-blown surround system requiring a minimum of 5 speakers plus subwoofer. A better solution appears in the selfsame Feb./Mar. '06 issue of Sound & Vision, a "Quick Take" on One-Box Surround: Yamaha YSP-800 Sound Projector. (The Yamaha web site says this about the unit.)

Yamaha YSP-800
This is, in fact, a 1-piece "digital sound projector" which, when paired with a powered subwoofer, gives you close to a 5.1-speaker audio experience. About 6" high and less than 32" wide, it can be placed on a shelf in front of a flat-panel display, or on a shelf below it, or (with optional wall-mounting bracket) on the wall above it. Like a digital A/V receiver, it receives audio inputs from various source devices such as a DVD player or cable-TV box. It processes them, amplifies them, and plays them through an array of 21 tweeters and 2 woofers. (The sound intended for the subwoofer is output on its own dedicated connection.)

It accepts both analog stereo and digital audio inputs, either optical or coaxial. "Sound beams" are derived, some of which are bounced off the walls of the room to simulate surround sound.

The reviewer, Ken C. Pohlmann, says the result is quite close to 5.1 surround, except that no sound comes from in back of you — only from the sides. I can live with that.

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