Sony Bravia KDL-55EX720 3D LCD HDTV HT Labs Measures

HT Labs Measures

Full-On/Full-Off Contrast Ratio: 18,220:1

The measurements were taken in the Custom Picture Mode, through an HDMI input.

The Sony’s black level measured an exceptional 0.001 foot-lamberts—the lowest sensitivity level of our lab-grade Minolta LS-100 light meter. However, the set’s peak white level is much more modest than most of the LCD sets we’ve seen. In Custom mode, post-calibration, it measured 22.59 ft-L with both the Picture and Backlight controls at maximum. While these maximum settings didn’t clip white, I nevertheless backed them off just a little (to 95 on Picture and 8 on the Backlight), both on principle and to leave some headroom for brighter room lighting or dimmer sources. This resulted in a peak white level of 18.22 ft-L. That was bright enough for me in subdued room lighting, at least for 2D, but your mileage may vary. The Vivid picture mode reached a maximum of 42.2 ft-L, but we can’t recommend that setting (among other reasons, it offers only two Color Temperature settings, both of them far too blue, and no user-menu White Balance calibration controls).

Recommended playback gammas usually range from 2.2 to 2.4, and the chosen gamma should be constant at each step from full brightness to near black (although in the real world, a slight variance with brightness is unavoidable). A Gamma setting of –1 on the Sony produced an average gamma of 2.13 at the dark end (20 to 40 IRE) and 1.93 at mid to high brightness (50 to 90 IRE). In the –3 setting (2D), the gamma measured just under 2.2 across much of the brightness range, but a too dark 2.58 at 20 IRE.

The Sony’s color performance was reasonably good out of the box in 2D. The Delta E for 2D, even before calibration, ranged from 2.55 to 5.23 from 20 IRE to 100 IRE. After calibration, this decreased to a maximum of 2.15. In 3D, the precalibration Delta E peaked at 9.49 at 100 IRE (below 4.48 at or below 90 IRE), which improved to a maximum of 0.31 from 20 to 90 IRE and 5.93 at 100 IRE.

With Live Color off, the Sony’s color gamut was very accurate (see the CIE chart above), with nearly precise color points and good measured brightness of each primary color with the Color control set to 53 to 54—though backing this off slightly to the default setting of 50 produced a subjectively more natural result on most program material.—TJN

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