Test Report: Panasonic TC-P55ST50 3D Plasma HDTV Page 3

Selections from my BD 3D reference collection that I screened on the Panasonic displayed good image depth and only a limited amount of ghosting (crosstalk). An exception was Hugo. This movie, which looked fantastic in the theater — it’s easily the best example of 3D filmmaking that’s been released since Avatar — displayed a notably high level of ghosting artifacts. Messing with the set’s 3D picture settings, including depth and left-right image swap adjustments, helped reduce the ghosting to a degree in a few scenes, but they were still a persistent, distracting presence. (To put things in context, a Samsung 3D plasma TV that I had on hand for comparison also revealed crosstalk in many scenes from Hugo, though the Panasonic’s performance here seemed slightly worse.) I also found the Panasonic’s 3D picture to be consistently dim. Even when viewing in a dark room with the contrast control maxed out (a separate 3D picture adjustment can be called up in all picture modes), I found that the Panasonic’s picture lacked an acceptable level of punch.

Despite the Panasonic P55ST50’s generally very impressive post-calibration performance, there were some areas where it came up lacking. Specifically, I noticed a degree of banding in several instances — an artifact that generally shows up in dark scenes and appears as a coarse, noisy gradation in flat background areas. And although the Panasonic‘s video processing was for the most part good, upconversion of standard-def images via the analog component-video input came across looking particularly soft.

Bottom Line

It’s hard to deny that you get a lot for your money with Panasonic’s P55ST50: a big 55-inch screen, 3D capability, loads of streaming options, built-in Wi-Fi. Still, tweaker types will want to also investigate the company’s more costly, THX-approved GT and VT Series, both of which offer a more extensive array of video adjustments. And although I found the P55ST50’s 3D performance to be somewhat unimpressive compared with other TVs I’ve recently tested, its overall picture quality is good enough that it could still be considered a steal at $1,600.

Extended Test Bench

Color temperature (Cinema preset before/Custom preset after calibration):

20-IRE: 6,346 K/ 6,093 K

30-IRE: 6,353 K/ 6,567 K

40-IRE: 6,393 K/ 6,670 K

50-IRE: 6,300 K/ 6,705 K

60-IRE: 6,245 K/ 6,649 K

70-IRE: 6,257 K/ 6,532 K

80-IRE: 6,086 K/ 6,453 K

90-IRE: 6,162 K/ 6,443 K

100-IRE: 6,111 K/ 6,344 K

* SpectraCal’s CalMan Professional monitor calibration software was used during the calibration and measurement process. See PDF link for a complete report with detailed pre- and post-calibration results.

The Panasonic TC-P55ST50’s Cinema picture/Warm 2 color temperature preset combination delivered the most accurate grayscale performance. Before calibration, color temperature averaged around 6,239 kelvins. After calibration, color temperature averaged 6,545 K. Primary and secondary color points measured slightly off from the HD standard. The set has no CMS adjustments available, so there was no way to improve upon its performance during calibration.

Gamma in the Cinema preset’s default setting measured somewhat below than the 2.2 target throughout the set’s full brightness range — a result that I was able to improve upon during calibration in Custom mode. The set’s black level measured 0.004 ftL in Custom — a notably better number than Panasonic’s TC-P55VT30 and Samsung’s PN59D8000 (both 2011 S+V Editor’s Choice award winners), which delivered a black level of 0.006 and 0.007 fTL, respectively. Picture uniformity was excellent with full-field patterns at all grayscale steps.

The set displayed full picture resolution for allsignal formats delivered via HDMI, though 480i-rez patterns looked soft when a component-video connection was used. Motion-resolution tests revealed a full 1,200 lines with the Motion Smoothing setting enabled and 700 lines when it was switched off. (Motion Smoothing added a distracting “video look” effect to film-based content at all settings, however.) The set aced most of our film and video deinterlacing tests when the 3:2 pulldown option was selected, slipping only on the HQV DVD’s 2:2 pulldown pattern. Its Video, Block, and Mosquito noise-reduction settings proved effective at all steps, and also didn’t introduce picture softening when applied to standard- or high-def signals. — A.G.