4K TV Reviews

As noted in the review, the black level of the set with a full-screen black test pattern was so low that the black level could not be accurately determined with the test tools we normally use. Even with the Backlight control at near its middle setting (10), the peak white level measured over 40 foot-lamberts—uncomfortably bright on dark scenes in a darkened room. I backed off to a Backlight level of 7 (Contrast on 90), which produced a comfortable peak white level of 35 ft-L.

BEFORE Calibration

AFTER Calibration

The pre-calibration RGB Balance shown in the accompanying chart was taken in the Movie mode, at the above 35 ft-L brightness level and with the Color Tone on Warm2. The pre-calibration gray scale Delta E values in this mode averaged 0.93 (!), with a maximum of 1.31 at 100%. While this hardly demanded any improvement, I went ahead and did a calibration, using only the 10p White Balance controls. The post-calibration, gray scale Delta E averaged 0.39, with a high of 1.00 at 90%.

(Delta E is a figure of merit that indicates how closely a display adheres to the Rec. 709 HD color standard. Experts generally agree that at levels below 3 to 4, the result is visibly indistinguishable from perfect color tracking. A Delta E may be used to characterize either white balance (gray scale), as above, or color, as below.

In the Rec. 709 color gamut setting, the color gamut’s pre-calibration color Delta E averaged a solid 2.3. After calibration, it averaged an exceptional 0.81, with a maximum of 2.4 in magenta (primarily for slightly excessive saturation). No other color’s Delta E was higher than 0.89 (blue).

With the Dynamic Contrast on Low (the setting I marginally preferred) and the Gamma control centered, the gamma averaged 2.17 with a low of 2.03 at 90% brightness and a high of 2.29 at 20%. With Dynamic Contrast Off, the average gamma was 2.26, with a high of 2.33 at 20% brightness and a low of 2.17 at 90%.—TJN