Thomas J. Norton

2D Performance
3D Performance
Features
Ergonomics
Value

Full LED backlighting with local dimming, when properly implemented, is the gold standard for achieving the best black levels in an LCD HDTV. But such a set also requires a lot of gold to acquire. LED edge-lit designs, needing fewer LEDs and less complex processing, cost less. While LG makes fully LEDbacklit local-dimming sets (its LM9600 Nano designs), the company’s premier, edge-lit LM8600 offerings also include local dimming. Local dimming, even in an edge-lit set, is usually better than none at all, but it’s less comprehensive and in theory less effective than the fully backlit variety. We reviewed the 55LM9600 Nano back in our September 2012 issue. But the 55LM8600 now lays down a strong challenge to its pricier sibling.

2D Performance
3D Performance
Features
Ergonomics
Value

All LCD HDTVs require some form of backlighting. The LCD panel’s pixels modulate the light and provide filtered color, but without backlighting to shine through the panel, you’d have no picture. Recently, LEDs (light-emitting diodes) have replaced the fluorescent backlights used in older flat-screen LCD sets. LCDs aren’t perfect in blocking light (which is why so many early models had poor black levels), but if you can shut off or dim the LEDs on demand, the LCDs’ light-blocking chores become far more efficient. And LEDs can do this; they can be shut off and turned back on almost instantaneously in reaction to the signal coming in.

But Sony's active 3D glasses, up to now, have been different. When using the company's HDTV 3D glasses, a 3D image on the Sony displays we've tested doesn't darken as you tilt your head from side to side. Instead, the left and right images break up, producing significant 3D crosstalk or, as this artifact is more colorfully known, ghosting. In addition, the Sony's 3D color varies with head position, shifting reddish with a tilt in one direction from vertical and bluish in the other. The latter effect makes it impossible to do a reliable 3D calibration; one eyepiece of the 3D glasses has to be placed over the lens of the measurement meter for a 3D calibration, and even a slight tilt can affect the result. Fortunately, the Sony 3D sets we've tested recently have produced visually satisfying 3D color even without a 3D calibration, though it's unlikely to be accurate. Nevertheless, the head-tilt ghosting and color shifting are annoying.