4K TV Reviews

The measurements were made using CalMAN measurement software from Portrait Displays, together with X-Rite i1Pro3 Plus and Klein's K-10A color meters and a Fresco 6-G pattern generator from Murideo.

SDR/HD
Full-On/Full-Off Contrast Ratio: Unmeasurable

In the Filmmaker Picture Mode, with the OLED Pixel Brightness at 80, Adjust Contrast at 85, Auto Dynamic Contrast and Peak Brightness Off, Gamma at 2.4, and Black Level at 51, the peak white level was 70.1 foot-Lamberts (240 nits) and the black level 0.000 foot-Lamberts, rendering the full-on/full-off contrast ratio unmeasurable.

With no changes to the set's out-of-the-box White Balance controls (all in their zero default settings), the Filmmaker mode's grayscale Delta E values ranged from a low of 0.39 at 30% to a high of 1.57 at 90%. The pre-calibration color Fine Tune Delta E values ranged from a high of 2.2 in red to a low of 0.30 in blue. Both the White Balance and Color Fine Tune out-of-the-box numbers above were remarkable, and required no adjustments to any of the calibration controls—the results were already first-rate.

A Rec.709 Saturation Sweep, analyzing all primary and secondary colors at saturation levels from 20% to 100%, produced excellent results with all Delta E values below 2.2. On a color checker test, which samples dozens of real world colors for accuracy, the maximum Delta E was 3.0 and the average 1.2. The G2 had excellent uniformity on a full field white pattern, with no obvious sign of the "dirty screen effect."

Delta E is a figure of merit that indicates how closely a display adheres to the color standard. Experts generally agree that at levels below 3.0-4.0 (most argue for 3.0) the result is visibly indistinguishable from perfect tracking. Delta E values may be used to characterize the accuracy of either white balance (grayscale), or color.

HDR10
Full-On/Full-Off Contrast Ratio: Unmeasurable

In the HDR10 Filmmaker Picture Mode, with OLED Peak Brightness at 100, Adjust Contrast at 100, Screen Brightness at 50, Auto Dynamic Contrast Off, HDR Tone Mapping Off (turned back on in normal use following calibration), and Peak Brightness set to High, the peak brightness was 925 nits and the black level 0.000 nits. The LG G1 we measured last year, under roughly the same conditions, produced 744.5 nits. That makes this year's G2, with its upgraded evo panel and new heat sink, 180.5 nits brighter for an increase of 24%. The HDR black level measured 0.000 nits, making the full-on/full-off contrast ratio unmeasurable. In these settings, the HDR EOTF (Electro Optical Transfer Function—roughly the gamma for HDR) was a nearly perfect match to an ideal result.

Before calibration the grayscale Delta E's ranged from a low of 0.25 at 20% to a high of 1.25 at 60%.

Before calibration the maximum Color Delta E (at 50% stimulation) was 2.7 in red and a minimum 0.7 in blue. As with the SDR results, no adjustments to the color calibration controls were needed to achieve these results. I have some thoughts as to how or why our G2 was so pristine out of the box in both HDR and SDR, but won't speculate on that here. But it does suggest that even if your sample isn't as near-perfect as ours, it should offer a range of control needed to make it so by a skilled calibrator.

The HDR 100% peak white levels, with luminance windows of varying sizes, measured 925 nits from 1% to 10%, 400 nits at 25%, 275 nits at 50%, and 170 nits at 100%. On an HDR Color Checker test (sampling a wide range of real colors and not just the primaries and secondaries), the G2 averaged a Delta E of 1.28 (1.97 maximum) with luminance included and 0.93 (1.99 max) without luminance. P3 and BT.709 saturation sweeps inside BT.2020 ranged from good to very good. The LG G2 measured 74.6% coverage of BT.2020 color and 99.2% of P3 (using the 1976 standard). The P3 result here is close enough to support a claim of full P3 coverage. No consumer source material as yet exceeds P3, and we know of no movement in that direction.—TJN