Panasonic TH-50PZ800 Plasma TV Setup & Tests
Tom Norton calibrated this set, so I asked him to discuss the process here:
In its THX mode, the TH-50PZ800's grayscale proved to be reasonably accurate out of the box—the only deviation was a blip of excessive red around 50 IRE. The calibration itself had to be performed in the service menu, as the THX mode offers no user-menu color-temperature controls. (Curiously, the THX mode adjustments in the service menu are labeled "Cinema," no doubt a holdover from the previous generation.)
Following calibration, the deviation from the optimum D65 grayscale was improved slightly at most points—except 50 IRE, where it was a bit worse. Note that all measurements were taken at a higher Picture (contrast) setting than the THX factory mode. Both settings allow the set to reproduce above-white, but the THX factory setting clips far more slowly above that point. The trade-off with the lower setting is a considerable sacrifice in image brightness.
In fact, using the Spears & Munsil test disc, the clipping pattern was totally washed out at Tom's higher Picture setting, even though above-white was visible on the Reverse Ramps with Steps pattern on Digital Video Essentials: HD Basics. I set the Picture control to the value that did not clip on Spears & Munsil, which did result in less light output, but it was still plenty for a dark room.
I double-checked this with The Fifth Element on DVD, which includes a shot of a guy in a white waiter's jacket with above-white information. The higher setting didn't seem to clip anything, though it did look too contrasty for my taste.
Unfortunately, the 50PZ800 does not display below-black, making it difficult to set the Brightness control. Once again, Spears & Munsil to the rescue—the PLUGE pattern on that disc includes a checkerboard pattern with squares of black and slightly above-black, which let me set Brightness accurately.
Another anomaly is that the Sharpness control seems to do absolutely nothing—no ringing, no sharpening, nothing at all. Horizontal black lines on a gray background have a dark shadow below them, but I was unable to see this effect on normal program material.
Oddly, setting the Format (aspect ratio) to Just does not result in 1:1 pixel mapping as I would expect. This is controlled by the HD Size parameter, which should be set to HD Size 2 to eliminate overscanning. (Format should be set to Full as well.)
Moving on to test discs, I started with the HQV Benchmark DVD at 480i via component. Detail was okay but not great, and jaggies were mild to moderate. Video NR (noise reduction) reduced noise without softening the picture, but MPEG NR softened the picture without reducing noise. The first time through the race-car loop, the set took more than a full second to lock onto 3:2 pulldown, but subsequent passes were much faster.
On the HQV Benchmark HD DVD at 1080i via HDMI, Video NR didn't do much at all to reduce noise, but MPEG NR still softened the picture slightly without doing anything about mosquito noise. The video resolution-loss test was solid as a rock, and jaggies were invisible, but there was some flickering at the edges of the high-frequency vertical bursts in the film resolution-loss test. In fact, the entire movement of the scrolling test pattern and the pan across the bleachers was slightly jerky, and there was moderate loss of detail in the bleacher seats during the pan.
Turning to FPD Benchmark on Blu-ray, the scrolling monoscope pattern was just a bit blurry—not as bad as a 60Hz LCD (or a 120Hz LCD with frame interpolation disabled), but not quite as sharp as other plasmas I've seen. The same was true of the other motion clips. The 0-100 ramp was pretty smooth, while the 0-25 ramp was more banded. The set came out of black fairly quickly, which I tend to like in real program material. The mostly black and mostly white shots had very good differentiation.