Panasonic 2010 G-Series Plasmas

The line of 2010 1080P Panasonic plasmas fall into three categories:

The G series improves over the S2 models in providing a THX mode for accurate color and a (mostly unusable due to flicker) 48 Hz mode for 1080p/24 inputs. It also offers a Custom mode where gamma and white balance adjustments can be made in the user menu, but these are also not very useful for reasons I will explain. So, the G series is basically the S2 series with the addition of a THX mode, which offers real benefit.

The V series improves on the G series in several ways. It offers a somewhat lower black level and has a 96 Hz mode that does a better job with 1080p/24 sources. It also offers even more custom calibration controls.

Some History

I had a chance to spend quite a bit of time with a 54" G25. By way of a little history, let me explain how it compares to Panasonic models of previous years. The 2008 Panasonic plasmas were very nice and were substantially improved over the 2007 models. The 2008 85Us correspond to the current S2 models. In this line there have been very few changes in core performance from 2008-2010.

On the other hand, the 2008 800U models, which correspond to this year's G-series, have undergone considerable changes. The 2009 G series was, well, disappointing. They were actually a step back from the mostly excellent 2008 800U's. Their light output in the THX mode was substantially lower (in the 26-28 fL range) and, even worse, the THX mode—whose sole raison d'etre is color accuracy—was compromised by a nasty color decoding error. I am pleased to report, as others have already, that this problem has been fixed in the G20/25, as has the light output problem, though at some cost elsewhere. Nonetheless, the 2010 G series does not perform in any measurable way any better than the 2008 800U. So, although Panasonic mid-range plasmas have not continued a downward spiral, they have not exactly been forging ahead either. All reports suggest that the V series (which I did not look at) has shown improvements in black level, but the black level of this new G25 was almost exactly what I saw with new 2008 models. No change here.

Black Level and Peak Output

After properly adjusting white and black levels in THX mode, I measured the following.

Peak output: 35 fL

Black Level: 0.009 fL

On/Off Contrast: 3996:1

Checkerboard Contrast: 1776:1 (35/0.02 fL)

I could have achieved considerably higher on/off contrast by simply pushing the panel harder. It seemed capable of at least 50 fL without clipping, but I prefer to leave the display at the SMPTE and THX-recommended level of 35 fL. Beyond that only induces eye fatigue, unnecessary panel wear, and increased problems with image retention. As you can see, the THX light output limitations of the 2009 models have clearly been resolved.

Gamma

The THX recommended gamma is 2.2. In theory, the ideal gamma is more like 2.35. Nonetheless, 2.2 offers a good compromise between shadow detail and image depth in a room with no light control. It seems clear that Panasonic engineers enabled the considerably higher light output in THX mode by ignoring the THX gamma standard, because the gamma on these sets is too low (gamma and light output are inversely related). Here's what I measured from both pre and post calibration gamma (they were essentially unchanged) in the THX mode.

Post-calibration, the gamma response averaged 2.08. In theory this should result in less image depth and higher light output. I certainly measured the latter, but the depth seemed subjectively good, so I am not sure how important this is. Of greater concern to me is the THX certification, the standards for which have now been clearly violated in Panasonic plasmas two years in a row.

Since this gamma response fell below expectations (and the measurements from both 2008 and 2009 models), I thought that I would try the Custom Mode, which makes available a Pro menu where further adjustments are available. These adjustments include different gamma settings that are unavailable in the THX mode. What I found was not encouraging. If the gamma response in THX mode was a little to low, in Custom Mode at ANY gamma setting, it was abysmal.

Here the gamma was much worse, even at the 2.4 setting (which was clearly no where near 2.4), which averaged 1.58 and was very non-linear, sloping downwards from the dark to the light end of the output range. I even tried experimenting with the panel brightness adjustment. This adjustment in the Pro menu seemed to affect the brightness of the panel at low levels while leaving peak output essentially unchanged. However, as much as I tried, I could not meaningfully improve upon the gamma curve regardless of what combination of gamma preset and panel brightness setting I choose.

My advice is to stay away from the Custom mode and stick with THX.

Grayscale

The results for grayscale tracking were much better. In fact, the only bad news in this regard is for custom calibrators. I was unable to meaningfully improve the THX grayscale by using the custom white balance controls in the service menu.

Grayscale Before

Grayscale After

I was able to lower the average CIELAB dE from 2.4 down to 1.6, but this improvement is below the threshold of visibility.

Color Accuracy

Finally, I am pleased to report that the color accuracy in the THX mode lives up to the billing. While not perfect, and not quite as good as you would get through the use of a custom color management system, for an unadjustable preset this is just about as good as it gets.

 

Conclusion

My reaction to this plasma is difficult to summarize because I have mixed feelings.

On the negative side, as good as it is, it still offers no meaningful improvement over the 2008 equivalent Panasonic model, and in the area of gamma it is actually worse. I also do not like the habit Panasonic has of offering useless and often misleading adjustments in the user menu (they are hardly alone in this). Labeling a gamma setting as 2.4 when it measures just under 1.6 is inexcusable.

However, on the positive side, taken on its own merits—or even comparing it to the current crop of available plasmas—it offers a really great image. The combination of low black level, accurate grayscale tracking, accurate color, excellent off-axis performance, and robust light output all put together in a 1080p 54" package produced a seductive, even stellar, image. Furthermore, taken on a performance-per-dollar basis, it beats the the 2008 models by a considerable margin. The owner of this plasma display purchased it for under $1,300. It is amazing what you can get now at a reasonably affordable price.

Since my evaluation of this unit is only a snapshot, I cannot comment on the notorious tendency of Panasonic black levels to rise over time. However, CNET recently reported that their 2010 model's black level did indeed rise after several months of use, but increased more gradually and to a lesser degree than did the 2009 models.

To get the best results from these sets, just select

There will obviously be some unit-to-unit variation, but these settings will get you in the ballpark of what this panel is capable of providing. I don't generally recommend specific settings, but in this case without an external processor to fix the gamma errors and slightly improve on color performance, there is very little more to get from a custom calibration. Just make reasonable selections in the user menu and call it a day.