LG 84LM9600 LCD Ultra HDTV Test Bench
Full-On/Full-Off Contrast ratio: 5,580:1
The above 2D result was obtained in the Expert1 Picture Mode with the Backlight on 60, the Contrast on 90, the Brightness at 43, the Gamma on 2.4, the Black Level on High, and the LED Local Dimming on Low (actually the most powerful setting). With local dimming in its High setting, the full-on/full-off contrast ratio was 2,635:1 (28.98 ft-L peak white, 0.011 ft-L black). With local dimming off, the full-on/full-off contrast ratio decreased to 663:1 (33.14 ft-L peak white, 0.05 ft-L black).
The Color Tracking charts show how well a display adheres to the D65 standard white point; the tighter the match of the three primary colors, the nearer the result is to D65. Before calibration, there was a measurable excess of red, and while the Delta E averaged a respectable 3.55, it shot to 5.10 or higher at 80 percent brightness and above, peaking at 7.07 at 100 percent. After calibration, and using just the 2-Point White Balance controls, Delta E averaged 0.84, with a maximum of 1.75 at 60 percent. The 20-Point controls can be used to fine-tune the 2-Point result, but my attempts to improve on the 2-Point result proved unrewarding so I elected to settle for the already solid 2-Point-only calibration. (Delta E indicates how close the color comes to the D65 HD standard at each point in the brightness range. Values below 3—some experts say 4—are considered visibly indistinguishable from ideal.)
The BT709 setting of the Color Gamut control placed the color points close to the positions called for by the Rec. 709 HDTV color standard. I found that while the Luminance controls in the CMS were effective, not all of the Saturation and Tint controls helped much; at times they didn’t move the points at all. But the final color gamut achieved (as shown in the CIE chart at soundandvision.com/testbench) was very good, with an average color Delta E of 0.82 (3.55 pre-calibration).
The final 3D calibration (charts not shown) was good as well, with an average White Balance Delta E of 0.92 (4.77 pre-calibration) and an average color Delta E of 1.17 (4.8 pre-calibration).
At a Gamma control setting of 2.4, the 2D gamma averaged 2.31. The 3D gamma averaged 2.12 at a (visually optimum) Gamma control setting of 2.2.—TJN