Our comparison involved a number of models from more expensive Panasonic series, including the TC-P46G10 and TC-P42S1, as well as a pair of large LCD displays, the Vizio VF550XVT and the Samsung LN52A650, in addition to our reference Pioneer PRO-111FD plasma and Sony KDL-55XBR8 LCD. Unfortunately, we didn't have any like-priced large-screen TVs to compare with the Panasonic TC-P50X1. We chose to watch "The Silence of the Lambs" on Blu-ray.
Black level: The Panasonic TC-P50X1's best picture quality characteristic is its capability to deliver a deep shade of black, which, as usual, lends the entire picture depth and pop in all lighting conditions. In a darkened home theater, watching dim scenes like the nighttime drive at the beginning of Chapter 7, the 50X1 handily out-blacked the LCDs (aside from the LED-powered Sony) and even looked a bit darker than Panasonic's own TC-P42S1 despite that more-expensive series' higher contrast ratio spec. The Panasonic G10 delivered a slightly deeper shade of black, however, and of course the Pioneer plasma was a good deal darker.
Shadow detail on the 50X1 was also solid, as evinced by the natural look of the subtle detail in brickwork in Chapter 6, with its realistic rise from black into shadow. Again, the G10 and Pioneer were the only ones in our lineup that obviously beat the 50X1 in this regard.
Color accuracy: The Panasonic 50X1 fell well short of ideal in this category, hindered by a highly inaccurate color of green compared with our reference display. The almost neon quality in green showed up very well in the night-vision view through Buffalo Bill's goggles, as well as in plants like the grass and trees around Quantico. The red Corolla next to Catherine Martin's car also appeared a bit too red.
The 50X1's bluish grayscale manifested, for example, as a bit too much paleness in Jodie Foster's face and in other delicate skin tones. We had to reduce the color control slightly to keep that tone natural-looking, but there was still plenty of saturation and "pop" left to colors, thanks to the 50X1's deep black levels. We were also very appreciative of the TV's consistent grayscale in dark areas, which didn't turn exceedingly bluish or greenish as we've seen on so many other displays, including the S1.
Video processing: As a non-1080p display, the TC-P50X1 can't be expected to resolve every detail of a 1080i or 1080p source, but it dealt with a static 720p source as well as can be expected. The set's nondefeatable 3 percent overscan prevented the extreme edges of the image from showing.
If you have a choice, we do recommend going in at 720p, mainly because the TC-P50X1 didn't correctly de-interlace 1080i content, whereas perhaps your external HD source will. We did not count lines to evaluate motion resolution (our test pattern only works properly with 1080p displays), but subjectively the 50X1 looked as sharp as the other plasmas with motion, and a bit sharper than the LCDs (aside from the Sony XBR8, which looked about the same).
It's also worth noting that with normal program material it was difficult to tell the difference in detail between the Pioneer and the Panasonic 50X1, despite the latter's significantly lower resolution spec (since both are 50-inch plasmas, they provide level ground for comparison). In the highest-detailed areas of our test footage, such as some computer-generated images from our Digital Video EssentialsBlu-ray, we could spot the overall softness in a side-by-side comparison, but in most other sources, including the "Silence" Blu-ray, we could barely differentiate the two from a seating distance of eight feet.
Uniformity: Most plasmas have nearly perfect screen uniformity, to the extent that we usually skip this section entirely in plasma TV reviews, but on the TC-P50X1 we encountered an issue we hadn't seen before. It might not be a classic uniformity artifact, such as off-angle problems or brightness variations across the screen--which were, as expected, basically nonexistent on this plasma--but it could be a deal-breaker for sharp-eyed viewers. Then again, most viewers probably won't notice it, at least until they read about it.
From seating distances closer than about 10 feet, we could make out a pattern of very faint, grayish diagonal lines that ran from the upper left to the lower right of the screen. The lines didn't move, but rather seemed to be a part of the screen or pixel structure. They showed up most in lighter areas, such as flat fields like the sky above the hospital and gray or white walls, as well as in lighter-skinned faces like that of Jody Foster as she stares at the newspaper clippings. In darker or noisier material the lines became much less apparent and often disappeared, but in many instances we could easily make them out--more easily the closer we sat to the screen (we find a seating distance of about 8 feet comfortable for a 50-inch screen). Once we noticed them, it was difficult to "un-see" the lines. Test patterns confirmed that the entire screen was affected.
We described what we saw to Panasonic, and the company's engineer said he would get back to us with an explanation. Panasonic did send us a second TC-P50X1 when we asked for it, to make sure that the issue wasn't confined to our particular review sample. Both looked basically the same, and both showed the lines. No adjustment we could make eliminated the issue.
Updated on May 28, 2009: The company got back to us with an explanation: "[Panasonic is] aware of the issue, but currently there is nothing that can be done to alleviate the lines. It is thought to be interference between the panel and front glass. At this time, a fix or software update to correct the phenomenon of the diagonal lines is not available. Engineers in Japan are continuing to study the phenomenon and investigate possible solutions and/or countermeasures."
Note that we have not yet tested a 42-inch Panasonic TC-P42X1, the TC-P50X1's smaller companion in the TC-PX1 series, so we can't say whether it shows similar lines. The two sets have different native resolutions, and since resolution could be a contributing factor to the lines, we are not going to apply this review to the 42-incher in a series review.
Bright lighting: The 50X1 did a solid job attenuating ambient light in a brightly lit room, but did not perform as well in this regard as the matte-screened Sony or the Pioneer plasmas did. We could make out some sharp reflections in the glass of the Panasonic's screen, and the light washed out the darker parts of the image worse than on the Samsung, but reflections still weren't as distracting as on that set. The 50X1's screen handled ambient light exactly like that of the other two Panasonic plasmas in our comparison.
Standard-definition: Standard-def picture quality on the TC-P50X1 was mediocre. It resolved every line of the DVD format, although details weren't quite as sharp as on the Samsung, for example. The 50X1 did a subpar job of moving diagonal lines and stripes on the waving American flag, leaving plenty of jaggies along the edges. Noise reduction was solid, on the other hand, and both Video NR and MPEG NR settings contributed to removing moving motes and snow from low-quality shots of skies and sunsets. Finally, the set properly engaged 2:3 pulldown to remove moire from the grandstands behind the racecar.
PC: The TC-P50X1 does not make an ideal large-screen PC monitor. Its lower resolution means onscreen text isn't as sharp as it would be on higher-resolution displays, it lacks a VGA input for analog connections from PCs, and the diagonal lines we described above are clearly visible on the white backgrounds common to PC desktops. When we connected three test PCs via HDMI, we were unable to get the native 1,366x768 resolution to appear as an option in the driver software; the best we could do was 1,280x768, which did look fairly good given the caveats above. Nonetheless, if you're planning on regularly using your HDTV as a big monitor, we recommend a different display.
|Before color temp (20/80)||6784/7027||Average|
|After color temp||N/A|
|Before grayscale variation||534||Average|
|After grayscale variation||N/A|
|Color of red (x/y)||0.664/0.329||Average|
|Color of green||0.253/0.672||Poor|
|Color of blue||0.149/0.057||Good|
|Defeatable edge enhancement||Y||Good|
|480i 2:3 pull-down, 24 fps||Pass||Good|
|1080i video resolution||Pass||Good|
|1080i film resolution||Fail||Poor|
Power consumption: Like all Panasonic plasmas we've tested recently, the TC-P50X1's default Standard picture mode is relatively dim (28.8ftl), which allows it to score well in our system, as well as qualify for Energy Star.
As usual, the best way to evaluate its efficiency is to compare it with like-size displays after calibration to a constant light level. On that playing field, the TC-P50X1 (255.88 watts) outclassed most recent 50-inch plasmas we've tested, including the Panasonic TH-50PF11UK (336.35), the Vizio VP505XVT (383.83), the LG 50PG30 (324.85), and the Samsung PN50A650 (337.77). That's because, unlike those 1080p models, the TC-P50X1 has a 720p resolution--plasmas, unlike LCDs, use more power at higher resolutions. Compared with 720p 50-inch plasmas, like the LG 50PG20 (257.59) and Hitachi P50H401 (216.65), the Panasonic TC-P50X1's power use is typical.
|Panasonic TC-P50X1||Picture settings|
|Picture on (watts)||217.95||255.88||N/A|
|Picture on (watts/sq. inch)||0.2||0.24||N/A|
|Cost per year||$47.11||$55.28||N/A|
|Score (considering size)||Good|