Do you need 1080p in a 42-inch flat panel? This is an important question, especially for plasma manufacturers that fear losing customers to the LCD camp at this highly coveted screen size. Up until now, plasma technology's cell structure has made it difficult to fit 1,920 by 1,080 pixels into a 42-inch screen size, which seems to have put them at a competitive disadvantage. As I write this, the first true 1080p 42-inch plasma (a Panasonic) is about to hit the shelves at a price of $2,500, but the market is already littered with 42-inch 1080p LCDs priced under $2,000. If consumers believe that they must have 1080p right now, it's fairly obvious which route they'll go.

"Believe" is the key word in that last sentence, but do they really need that much resolution in a 42-inch display? As I type this, I can hear video editor Geoffrey Morrison screaming, "No, they don't! Didn't anybody read my highly insightful story about viewing distance versus resolution in the January 2005 issue?" (He's quite humble, you know.) If you're a videophile who likes the idea of feeding as pure a source as possible into your TV, then you might appreciate a 42-inch panel that can accept a 1080p high-definition DVD signal with minimal scaling or deinterlacing needed on the TV's part. However, if you just want 1080p because you believe you're going to see a more detailed picture, you probably won't—unless you plan to sit only about 5 feet from the TV set.

Why am I engaging in this debate in this particular TV review? Because the new P42H401 plasma HDTV is Hitachi's attempt to give people what they think they need—1,080 lines of vertical resolution—at a price they want: $1,700. On paper, the P42H401 has a 1,024-by-1,080 resolution. Even though the horizontal resolution is not 1,920, its vertical resolution would qualify it as a 1080p display if not for one small issue: Not all 1,080 lines are illuminated at the same time, as they are in a true progressive display.

To fit all 1,080 lines on that 42-inch glass substrate, this display employs the technology formerly known as ALiS (Alternate Lighting of Surfaces), now dubbed HD1080. In a standard plasma design, each row of pixels requires two electrode strips (one at the top and one at the bottom), so every two rows require four strips. HD1080 shares one electrode strip between each pair of rows, so every two rows require three electrode strips. This reduction in the overall number of electrode strips allows for more space to fit 1,080 rows. The trade-off is that the display can't illuminate both rows at the same time, so the plasma alternately lights each row every sixtieth of a second. In other words, at any given sixtieth of a second, you're seeing 540 lines, somewhat akin to a 1080i CRT display.

I could probably devote an entire technical paper to dissecting the specifics of HD1080—what's going on at the processing stage, would you be better off with a 1,024-by-768 panel, and so on. Ultimately, though, it comes down to one simple question: How does the picture look with this particular plasma TV?

Reading Between the Lines
The nature of HD1080 makes it difficult to evaluate the P42H401's performance using our standard test discs. In the area of detail, our Video Essentials resolution pattern shows that the P42H401 measures out to the limits with DVD, but it was difficult to get a firm estimate for 720p and 1080i (see our measurements text). Sitting about 7.5 feet from the screen, I was generally satisfied with the detail I saw in all sources: SDTV, DVD, HDTV, and high-definition DVD. Facial close-ups in the Training Day HD DVD revealed a solid amount of fine detail.

Video processing is also tricky. Because you never see a progressive image on the screen, it's hard to know exactly what the P42H401's 1080p PictureMaster IV video processor is doing behind the scenes. Rather than get overly technical in an attempt to explain what we think we gleaned from test patterns, let me just tell you what I saw with real-world content. With the P42H401's Auto Movie mode turned on, the stadium pan on the HQV Benchmark HD DVD test disc—which can be filled with moiré patterns when a display doesn't pick up the 3:2 sequence with 1080i film—was wonderfully smooth. Likewise, I saw few artifacts with film-based 1080i HDTV and HD DVD content. Video-based 1080i content wasn't as clean but was on par with other HD displays I've reviewed. The P42H401 accepts 1080p/60 through its HDMI inputs but not its component video inputs; it doesn't accept 1080p/24 through either input type.

As for its handling of standard-definition content, the TV struggled a bit with the Coliseum flyover in chapter 12 of Gladiator: Much of the scene was clean, but it created patches of jaggies around the screen. It was also slow to pick up the 3:2 sequence in chapter 3 of The Bourne Identity but looked clean once it did so. This, and the fact that the TV has an Auto Movie mode implies that, at some point, the display converts all signals to progressive before it interlaces them for the panel. The TV did a better job than my cable box of upconverting a 480i airing of The Colbert Report, creating fewer visible lines and scaling artifacts. So, while it wasn't outstanding, SD processing was generally solid.

The P42H401 has three preset picture modes—Day (Dynamic), Day (Normal), and Night—to which you can make separate adjustments for each input. There are also three color temperatures (High, Medium, and Standard). In the Standard mode, the color temperature is a little warm at the low end, so darker content looks a bit red; calibration didn't make much of an improvement. I've yet to see a plasma with an accurate green color point, but this one is more exaggerated than many; the grass in ESPN HD's Sunday Night Baseball and chapter 3 of Kill Bill Volume 1 was too electric for my taste. Beyond that, I found that colors looked pleasing and skintones natural.

One of ALiS' reported drawbacks is that it hinders black level, and that was definitely the case here. We measured 0.084 foot-lamberts with an all-black test pattern; that's about twice as high as any plasma we've reviewed over the past year. Blacks in the Corpse Bride and V for Vendetta HD DVDs looked more gray, and the higher black level limits color saturation and image depth in a dark room. The TV's light output is on par with many plasmas we've reviewed: We measured 21.74 ft-L on a full-white field and 57.27 ft-L in a 100-IRE window, which is arguably a better indication of real-world content. While not spectacular, these numbers are good enough that I was able to enjoy a saturated image during the day, in a moderately lit environment. Still, that higher black level brings down the overall contrast ratio, so the picture lacks that truly rich, three-dimensional quality that brings an image to life on the screen.

Finally, the P42H401 spec sheet claims 16-bit color, but I did not see that level of gradation in colors and light-to-dark transitions—which makes me wonder if HD1080 affects how much bit depth we're really seeing. Through both the component and HDMI inputs, the TV created noticeable steps in the Video Essentials white-to-black test ramp, resulting in a picture that often revealed its digital nature. The amount of noise wasn't intolerable, but it was ever-present—in background colors of DVDs and HDTV shows and particularly in dark scenes with complex shading, such as chapter 3 of the V for Vendetta HD DVD and chapter 5 of the Corpse Bride HD DVDs. Brighter HD scenes from Training Day and Batman Begins were generally clean.

Overall, the P42H401 is a solid everyday television. Its detail, color, and processing help it perform well with a wide range of sources in various viewing environments, but it lacks the high-end refinement that a discerning enthusiast would desire. That $1,700 price point may up the appeal for the average consumer, but I'd be remiss if I didn't point out that you can find better-performing 42-inch 768p plasmas in the same price range. If you simply must have that 1080 spec, the P42H401 delivers.

Highlights
• 1080 minus the "p"
• Three HDMI inputs
• Competitively priced at $1,700