Panasonic TC-P65VT50 3D Plasma HDTV HT Labs Measures

HT Labs Measures

Full-On/Full-Off Contrast Ratio: 16,165:1

All the post-calibration measurements shown here and all the observations in the review itself unless noted otherwise were performed in the Custom picture mode for 2D and 3D, through an HDMI input with the set adjusted as needed for the most accurate image in a darkened room.

The above 2D contrast ratio was measured at a Contrast setting of 79, a Brightness setting of 57, and a Gamma setting of 2.4, and Panel brightness set to Mid. The peak white level with these settings was 32.33 foot-lamberts, and the black level was 0.002 ft-L.

The Before Calibration RGB Balance shown in the charts was taken in the THX Cinema mode, adjusted for approximately the same peak white level mentioned above and the Color temp. set to Warm2. As you can see, the result was middling at best. The pre-calibration Delta E values ranged from 2.16 at 20 percent brightness (good) to 7.42 at 80 percent, with an average of 5.18. Post-calibration in the Custom mode, the low was 0.26 at 60 percent and the high 1.59 at 100 percent, for an excellent average of 0.62.

(Delta E is a figure of merit that indicates how closely a display adheres to the HD color standard. Experts generally agree that a level below 3 to 4 indicates a result that’s visibly indistinguishable from perfect color tracking. Delta Es can be used to characterize either white balance [gray scale] or color.)

In the Normal Color space setting, the set’s post-calibration 2D color gamut was close to the Rec. 709 HD standard with respect to the two-dimensional locations of the color points as shown on the CIE chart. The luminance values of the individual colors, however, were off. Unfortunately, the Luminance controls in the Pro menu proved largely useless for correcting this. With a little finessing of the main Color control (taking care to avoid adverse effects on the other color results), I was able to refine the overall post-calibration color Delta E values to an excellent average of 0.65—a high of 0.72 for cyan and a low of 0.51 for magenta.

The Panasonic’s gamma in the 2D Custom mode, at a setting of 2.4, averaged 2.23, with a low of 2.21 at 80 percent brightness and a high of 2.26 at 60 percent.

The 3D calibration (charts not shown) came out nearly as well. Post-calibration, the gray scale Delta E averaged 0.86 and the color Delta E averaged 4.92 (with green the outlier at 16.63; blue was the next highest at 5.4). At a Gamma setting of 2.2, which looked visibly best overall on most 3D material, the average gamma was a low 1.72 (high 1.97 at 20 percent, low 0.83—ulp!—at 90 percent). It’s now a relatively common practice for manufacturers to pump up the subjective 3D brightness level by using low gammas, which enhances the mid-brightness region. —TJN

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