Test Report: LG 55LM7600 3D LCD HDTV Page 3

As I noted when watching 3D, the 55LM7600 can create a bright, punchy image. At a reasonable brightness setting, however, its black level was only about average. During a murky, moody movie like Tinker Tailor Soldier Spy, the 55LM7600’s strengths and weaknesses became quite apparent: The film’s muted color palate was reproduced well, but the TV’s only-average black level prevented it from “disappearing” into the background the way a better plasma TV can, and the motion blurred fine details slightly. The LG’s colors are nearly spot-on, however, making for a fairly accurate image in that regard.

Internet streaming services like Netflix and Hulu Plus work as you’d expect, though navigating the menus is a little slow. Interestingly, they use a different picture menu entirely, with different settings. So you’ll need to adjust the picture settings independently for streaming, and without the benefit of test patterns from a setup disc.

Video processing was about average, with the 1080i-format rotating bar test pattern from the Spears & Munsil High Definition Benchmark Blu-ray starting to show jaggies on diagonals at around 25°. The 1080i ship clip showed similar performance, with noticeable jaggies on the rigging and other near-horizontal lines. Upconversion of standard-def content was excellent, with lots of detail and minimal noise or jaggies.

The area where the 55LM7600 proved noticeably mediocre was brightness uniformity. As with nearly all edge-lit LED LCDs, there was significant light leakage at the lower corners of the screen and a few other seemingly random areas along the edges. This was especially noticeable with darker scenes. I’ve seen worse TVs in this regard, but not many, and none this expensive. The “local” dimming feature helped here somewhat, but at higher settings it often made the picture unevenness even worse by making the screen’s edges noticeably darker. Off-axis performance was likewise average, with the black level rising and taking on a bluish hue starting at about 30° off center.

Bottom Line

On the whole, I like LG’s 55LM7600. I like its Magic Remote, though I can see some conservative traditionalists being terrified of a new control scheme. I love its Smart TV interface, which is something that LG has done extremely well over the years. And its passive 3D tech offers benefits over active 3D, and is quite pleasing to watch. But even though the 55LM7600’s overall video performance turned out to be decent, I expected more for $2,100. As a content hub for your digital world, however, the 55LM7600 is quite good and well worth checking out.

Test Bench

Color temperature (Expert1 picture mode before/after calibration)

20-IRE: 7,655 K/ 6,638 K

30-IRE: 7,534 K/ 6,563 K

40-IRE: 7,527 K/ 6,550 K

50-IRE: 7,512 K/ 6,504 K

60-IRE: 7,468 K/ 6,483 K

70-IRE: 7,452 K/ 6,545 K

80-IRE: 7,464 K/ 6,579 K

90-IRE: 7,529 K/ 6,615 K

100-IRE: 7,264 K/ 7,036 K

Primary Color Point Accuracy vs. SMPTE HD Standard

Color

Target X

Measured X

Target Y

Measured Y

Red

0.64

0.64

0.33

0.33

Green

0.30

0.31

0.60

0.60

Blue

0.15

0.15

0.06

0.06

With its Expert1 picture and Warm color temperature modes selected, the LG 55LM7600 measures fairly cool across the grayscale range, averaging 989 kelvins off from the D6500 standard. Two color temp calibration methods are available: a 2-step (high/low) and a 20-step. Both were buggy, with the 2-step high setting adjusting the low end of the grayscale range and vice versa. The 20-step method only adjusted part of the range. No points were deducted in the rating for this, as the post-calibration numbers using the 2-step method were reasonable. Color points all measured nearly spot-on.

With the backlight set at 100, maximum light output was an impressive 118.4 ftL. Black level at that setting was 0.029, for a contrast ratio of 4,083:1. With the backlight set at 0, the numbers were 5.483 ftL and 0.0012, for a contrast ratio of 4569:1. I found a backlight setting of 40-60 to be optimal for my darkened room testing. At a setting of 50, the LG produced 62.39 and 0.015 ftL for a contrast ratio of 4159:1. The LED Plus “local” dimming didn’t meaningfully change these numbers, and as it generally made the center of the image noticeably brighter than the edges, I left this feature off during the majority of my testing.

In the Just Scan mode, the 55LM7600 crops two lines each from the top and bottom, and two columns of pixels from the right side. It can resolve a 1-pixel on/off pattern at 1080p.

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