Sony Bravia XBR-55HX929 3D LED LCD HDTV HT Labs Measures
HT Labs Measures
Full-On/Full-Off Contrast Ratio: Unmeasurable
The measurements were taken in the Custom Picture Mode, through an HDMI input.
With the backlight set to 4, the picture (Contrast) control at 70, the brightness at 53, the gamma on +2, and the LED Dynamic Control on Standard, the peak white level was just slightly below 30 foot-lamberts. The black level was unmeasurable with our Minolta LS-100 light meter—resulting in an unmeasurable full-on/full-off contrast ratio.
The Max setting of the backlight control is 10, leaving ample overhead from the above settings (4) should you feel the need for higher brightness. For example, with the backlight turned to Max in Custom, the peak white level was 53 ft-L. In Vivid, it was 160 ft-L. But for a dark room, we have found that 30 ft-L is more than bright enough and easy on the eyes.
With the LED Dynamic Control on low and the other settings unchanged, the peak white level was 29.6 ft-L and the black level 0.004, for a full-on/full-off contrast ratio of 14,800:1. With the LED Dynamic Control off, the relative measurements were 30 ft-L white and 0.021 black (a very mediocre number in today’s market), for a full-on/full-off contrast ratio of 1,429:1. We recommend leaving LED Dynamic Contrast in its standard setting.
The black levels for the low and off settings were taken immediately after the image dropped to black. In those settings, the black levels dropped an additional degree shortly after the reading was made. In its +2 setting, the gamma ranged from 2.05 in the midrange to 2.12 at the dark (20 IRE) and bright (90 IRE) ends of the brightness spectrum. The +1 gamma setting was closer to the typically recommended gamma of 2.2, but on most material, it looked a little too crushed on the dark end. Your mileage may vary.
The pre-calibration color temperature was around 6700K in its optimum setting of Warm 2. The Before Calibration color-tracking chart shows that this result was nevertheless lacking in green, and the Delta Es ranged from 10.9 to 14.7. After a 2D calibration, the maximum Delta E was 2.22 at 20 IRE, and the next worst value was 1.35—a superb result. The color gamut, with Live Color off (see the CIE chart) was very accurate, although it required a slight reduction in the Color control from the default setting of 50 to produce a respectably accurate brightness level for each color.
The color was not calibrated separately for 3D for reasons described in the main text. But I did measure a 3D peak white level of about 14.1 ft-L and a black level of 0.001 ft-L, for a full-on/full-off 3D contrast ratio of 14,100:1 (with the backlight at max, the picture on 70, the brightness on 43, the gamma on –1, and LED Dynamic Control on standard).—TJN