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Panasonic Viera TC-PG20 review:

Panasonic Viera TC-PG20

Panasonic has equipped the TC-PG20/25 series with an array of picture settings that finally places it on a par with other makers' TVs. The Pro Settings menu, available only in the Custom picture mode, offers niceties like a fine color temperature menu (a measly four points is still better than none) and an array of gamma choices, both of which allow tweakers some leeway. We also like that, unlike on LG's so-equipped TVs, Panasonic's THX mode can be adjusted. Said tweakers will also note the new-for-2010 "blur reduction" setting described thusly: "Improves motion picture quality. Additional sub-fields are created to reduce motion blur." See Performance for details.

Panasonic offers a THX-certified picture preset that allows some basic adjustment.

Other features
Power saver mode No Ambient light sensor Yes
Picture-in-picture No On-screen user manual No
Other: Two modes to combat burn-in

Watchers paranoid about

HDMI inputs 2 back, 1 side Component video inputs 2 back
Composite video input(s) 1 back, 1 side S-video input(s) 0
VGA-style PC input(s) 1 RF input(s) 1
AV output(s) 0 Digital audio output Optical
USB port 2 side Ethernet (LAN) port Yes
Other: Side SD card slot

Three HDMI inputs total falls one short of most 2010 HDTVs we've tested but should still be plenty for most setups. The SD card slot can handle video, photos, and music, like the USB ports, and the second USB is a nice addition if you use the first for the optional Wi-Fi dongle.

Two HDMI inputs on the back panel might not be enough for elaborate home theaters.

A third HDMI is located on the side. Few TVs have an SD card slot nowadays, but we'll warrant even fewer viewers care.

The TC-PG20/25 delivered excellent overall picture quality. Deep black levels were a strength, color accuracy was very good in THX mode, and the typical uniformity advantages of plasma over LCD--excellent off-angle fidelity, uniform brightness and color across the screen--were in abundant evidence. The main hiccup we encountered was the inability to handle 1080p/24 content properly.

TV settings: Panasonic TC-P50G20

The THX mode was clearly the most accurate before adjustment. It evinced a smooth grayscale that fell within the D65 ballpark (although it was minus-blue overall), decent gamma (2.07 average, versus a target of 2.2) and, unlike last year, plenty of light output (37 ftl) with some headroom for adjustment. Best of all, there was no overt greenish tinge thanks to improved color decoding. We'd love the option to tweak THX further and improve these areas, but the Pro adjust menu, which contains the relevant settings, was inactive in THX mode.

Update June 2, 2010: Based upon reader requests for further testing we have noted a couple of other performance-related issues with the G20/25 series. We don't consider either one significant enough to warrant a ratings reduction, but since neither was evident on 2009 Panasonic plasmas, we feel they deserve mention. The first, fluctuating black levels, is detailed further in the review.

The second manifests as a faint buzzing noise that becomes louder as light output increases. In most cases it remained quieter than the clicking of the hard drive in our DVR, but in some scenes, especially where a bright light flashed on and off on the screen, it was more noticeable. Since we often watch with relatively low light output, we didn't notice the noise until a reader pointed it out, so we definitely don't consider it a deal-breaker. Nevertheless, the G20/25 is louder than most TVs we've tested, so the sensitive-of-ear should audition this plasma in person, preferably in a quiet room with a bright picture, before taking the plunge. The noise emitted by the Panasonic TC-PVT20/25, though audible as well if you listen hard, is significantly quieter.

We tried calibrating the Custom mode, which does allow tweaks to the Pro adjust menu, but while we were able to improve the grayscale compared to THX, other areas of picture quality--namely gamma, color decoding and primary/secondary color accuracy--were significantly worse. In the past, such as on the V10 last year, our adjustments in Custom yielded very good gamma results, but not this time around.

THX was still better overall than Custom, so we used it, with some tiny tweaks, for our evaluation. We checked out the Blu-ray of Invictus, with the comparison lineup below, for our main image quality tests.

Comparison models (details)
LG 50PK750 50-inch plasma
Panasonic TC-P50V10 50-inch plasma
Samsung PN50B650 50-inch plasma
LG 47LE8500 47-inch full array local dimming LED
Samsung UN55C8000 55-inch edge-lit local dimming LED
Pioneer PRO-111FD (reference) 50-inch plasma

Black level: Our nearly new TC-PG20/25 sample performed extremely well in this area, with the kind of deep, inky blacks we've come to expect from the company's plasma TVs. It lagged behind the Pioneer and the LG LE8500 in this area, but outperformed the others, including the slightly-aged V10 from last year. The differences were most visible in dark scenes, such as the shot down the road outside Mandela's house at the 40 minute mark. The black of a leather jacket, the night sky, the shadows under the trees and the letterbox bars appeared just a bit inkier than on the V10 and both of the Samsungs, and a good deal deeper than the LG PK750 plasma. In brighter scenes the differences between the various displays' black levels narrowed significantly, as usual, although they were still visible in the letterbox bars.

We measured a black level of 0.001 footlamberts (ftl) for the Pioneer and LG LH8500, 0.007 on the G20/25, 0.016 for the V10 (at about 1,200 hours), 0.018 for the Samsung B650, and 0.024 for the LG PK750. We ran the G20/25 for about 100 hours after we received it and that measurement didn't shift. If behavior from the 2009 models is any indication, we don't expect any change for at least a few hundred hours (typical TV use is 1,900 hours/year), but if/when we measure one, we'll update this review.

Details in shadows on the G20/25 series appeared a bit less natural than on some of the sets in our lineup. We attribute this issue to the TV's lighter gamma in dark areas, which made the shaded bush alongside Mandela's wall, and the shadowed faces of Pienaar and Nerine in Chapter 15, for example, a bit brighter than on the Pioneer or the LG LE8500. This wasn't a major issue however, and shadows and near-dark areas still looked realistic overall, mainly owing to the G20/25's deep blacks.

Like some Panasonic plasma models we've seen in past years, the G20/25 also evinced fluctuating black levels in some circumstances. Test patterns revealed a sudden brightening of "black" when the average picture brightness rose above a certain level (namely when a 100% window pattern was displayed; the 95% and lower window patterns did not cause the brightening). We looked for evidence of this brightening in program material, such as dark areas of brighter scenes from Invictus (Chapter 1) and I Am Legend (Chapter 4) and while there seemed to be some fluctuation, it wasn't as obvious as in test patterns. Other material might reveal the fluctuation more obviously, but in scenes we watched the G20/25 maintained a stable-enough black that we don't consider this a serious-enough issue to change our overall rating. The TC-PVT20/25 we tested did not evince any such fluctuation.

Color accuracy: In THX mode the G20/25 performed very well in this area, although due to its less-than-perfect grayscale it still fell a bit short of our reference display and a couple of the others in our lineup (including the V10 and the PK750). We noticed skin tones, like the faces of Pienaar's family in Chapter 9, seemed very slightly paler and shifted toward green, although not nearly to the extent we saw on last year's THX mode, for example. The light blue shirt of Mr. Pienaar and the red couch cushion exhibited a similar slight shift. We'd be hard-pressed to notice the difference without the benefit of a side-by-side a comparison, however.

Primary and secondary color accuracy was excellent, as evinced by the green of the grass and trees around the white players' field in Chapter 1, for example. The TV's deep black levels and solid color decoding contributed to some of the most saturated, punchy colors in our lineup. We also appreciated that black areas stayed a relatively neutral color on the G20/25, as opposed to veering into blue as we saw on the Samsung LCD and the PK750, for example.

Video processing: Panasonic makes a lot of marketing hay out of its 600Hz subfield drive, but as we observed last year, its benefits (much like the antiblurring effects of 120Hz, 240Hz etc LCDs) are exceedingly difficult to discern. When we engaged the Blur reduction setting, our motion resolution test showed that the G20/25 was delivering all 1080 lines of the source. When we turned off the control, the result dipped down to somewhere between 700-800 lines. Although the difference between the two settings was impossible for us to see outside of specialized test patterns, there's no obvious reason not to turn the control on--it introduced no negative effects we could see.

As we noted above the G20/25 series is not blessed with the 96Hz refresh rate found on the step-up VT20/25 models, so as we observed with Panasonic's predecessor plasmas from 2009, the G models cannot properly handle 1080p/24 sources. We confirmed this with our favorite scene for such a test, the flyover of the Intrepid from "I Am Legend," where we observed the characteristic stuttering motion of 2:3 pull-down (as opposed to the correct cadence of film we observed on the V10) when the G20/25 was set to its default 60Hz mode under "24p direct in." Switching to the other option, 48Hz, caused the display to flicker significantly and become essentially unwatchable, especially in brighter scenes.

In our 1080i deinterlacing test, it's worth noting that the G20/G25 only passed in film mode when we chose the "on" position for the 3:2 pull-down control. When the control was set to the default "Auto" position, the TV failed.

Bright lighting: Panasonic has improved its antireflective screen quite a bit compared to 2009, and the difference was clearly visible by comparing the G20/25 to the V10 in a well-lit room. The screen preserved black levels better and further reduced the brightness of reflections, such as the faces of viewers or even lamps caught in the screen. It beat the LG models in both of these areas, although it wasn't as good as the Pioneer. Compared to the Samsungs, the G20/25's screen did a better job reducing reflections, but didn't preserve black levels nearly as well.

Standard-definition: The 2010 G series is one of the worst standard-def performers we've tested recently. It didn't quite resolve all of the horizontal detail of the DVD format, and the shots of the stone bridge and grass appeared a bit soft. Jaggies in moving diagonal lines and a waving American flag were more prevalent on the G20/25 than on the Samsung or LG plasmas. Noise reduction was also less effective; in the Panasonic's strongest setting, we still saw motes and video noise in low-quality shots of skies and sunsets. The TV passed the 2:3 pull-down test in "On" mode, but the default "Auto" was again ineffective.

PC: Via analog VGA the TC-PG20/25 accepted a maximum input signal of 1,366x768, which is disappointing for a 1080p TV. Text in that resolution looked relatively soft, and we missed having an autoadjust function to fill the screen properly, but after some tweaking it looked passable. Via HDMI the TV handled every line of a 1,920x1,080 source with no edge enhancement or softness and excellent overall quality.

Geek box
Before color temp (20/80) 6495/6176 Good
After color temp N/A  
Before grayscale variation 294 Good
After grayscale variation N/A  
Color of red (x/y) 0.642/0.33 Good
Color of green 0.302/0.6 Good
Color of blue 0.15/0.058 Good
Overscan 0.0% Good
Defeatable edge enhancement Yes Poor
480i 2:3 pull-down, 24 fps Pass Good
1080i video resolution Pass Good
1080i film resolution Pass Good

Power consumption: We did not test the power consumption of this size in the Panasonic TC-PG20/25 series series, but we did test a 50-inch model. For more information, refer to the review of the Panasonic TC-P50G20. How we test TVs

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