Picture settings: Five tweakable picture modes, a gamma slider, a full color management system and a two-point grayscale control place the 640U squarely in the middle of the pack for adjustability. New for 2012 is the ability to tweak the strength of dejudder from really smooth to even smoother.
Connectivity: I have no complaints on this front. Four HDMI is plenty, and the analog connections (one component, two composite, one VGA for computers) are as complete as I'd expect. A pair of USB ports, one facing the side and one the bottom, rounds out the package.
The LC-LE640U performs better than what I remember of last year's , thanks primarily to somewhat better uniformity and perhaps deeper black levels. It won't blow videophiles away, however: blacks are still grayish compared to better LEDs and plasmas, while uniformity and off-angle were still issues. I appreciated its color accuracy and matte screen, but unfortunately video processing took a step backward.
Click the image at the right to see the picture settings used in the review and to read more about how this TV's picture controls worked during calibration.
|Comparison models (details)|
|46 inch LCD|
|55 inch edge-lit LED|
|55 inch edge-lit LED|
|47 inch edge-lit LED|
|reference) (||60 inch full-array LED|
Black level: The Sharp performed worse in this department than most of the others in the lineup when I checked out "Harry Potter and the Deathly Hallows: Part 1." In dark scenes its blacks were generally as deep as those of the Samsung and a bit brighter than the LG and the Vizio. Mixed scenes, like the face of Snape as he strides across the grounds (4:10), looked punchier if a bit less accurate on the Vizio and about the same as on the LG and Samsung. As expected the Sony and Elite trounced the others, including the Sharp, in this category.
Details in shadows, like the dark clothing of the evildoers in Chapter 1, looked good, with more realism than on the Samsung if a bit less of a natural look than on the Elite or the Sony.
Speaking of unnatural, I was annoyed when the Sharp's backlight turned off completely and then abruptly fired up again at the 9:50 and 10:01 marks after fades to black. I prefer the smoother fades of most of the other sets, whose backlights remained on or undimmed gradually enough not to notice.
Color accuracy: Overall the 640U fared well at rendering skin tones and other colors, approaching the color palette of the very accurate LG and Vizio and appearing a bit more accurate than most of the others in the gathering in Chapter 3, for example.
On the 830U last year I complained about the overly blue-tinged blacks, but on the 640U they weren't as obvious. Shadows and black areas appeared less blue and more inaccurate on the Sony and Samsung displays, although the rest of the lineup outdid the Sharp in this area.
Video processing: Unlike last year's models such as the LC-830U series, the 2012 640U was not capable of passing the correct 1080p/24 film cadence in our test. Instead, the deck of the Intrepid from "I Am Legend" showed either the choppy stutter of 2:3 pull-down or the too-smooth look of dejudder. The former occurred when I set Film Mode to either Off or Advanced (0), while any of the other Advanced values caused dejudder to kick in.
Despite the presence of 11 smoothness settings, the adjustable dejudder basically toggled between Off (at 0) and Really Smooth (+1 or higher). We'd like to have seen a greater range of visible effect, such as Samsung's system provides, or even a single setting that keeps some judder, like Sony's Standard setting.
One video processing bright spot was the Sharp's ability to preserve its full-motion resolution--about 600 lines in this case, typical for a 120Hz TV--without introducing dejudder.
Uniformity: My biggest complaint against the 830U last year centered on its poor screen uniformity, and while Sharp improved that issue on the 640U sample I tested, it was still the worst in our lineup. A slightly brighter blotch in the left-center of the screen was visible in test patterns, and while it wasn't obvious in most material, I noticed it occasionally during camera movement, for example the pan over the bad guys in Chapter 2. Test patterns also revealed a few other blotchy spots in our review sample, but none were as visible or annoying during program material.
From off-angle the Sharp lost black level and color fidelity (becoming bluer-tinged) at about the same rate as the Samsung, and kept black level (but not color) marginally better than the LG and Vizios. Both the Sony and the Elite were better from off-angle than the Sharp.
Bright lighting: The Sharp's matte screen was very good at rejecting reflections from ambient light, doing about as well as the other matte LCDs (the LG, the Vizio and the Samsung) in our bright room. It didn't preserve black levels as well as the glossy Sony or Elite screens, however, and even fell a bit short of the other matte screens in this regard.
|Black luminance (0%)||0.0061||Good|
|Near-black x/y (5%)||0.3242/0.3385||Average|
|Dark gray x/y (20%)||0.3118/0.327||Good|
|Bright gray x/y (70%)||0.3124/0.3284||Good|
|Before avg. color temp.||6611||Average|
|After avg. color temp.||6451||Good|
|Red lum. error (de94_L)||1.134||Good|
|Green lum. error (de94_L)||0.4019||Good|
|Blue lum. error (de94_L)||0.5391||Good|
|Cyan hue x/y||0.2295/0.3303||Good|
|Magenta hue x/y||0.3231/0.1463||Good|
|Yellow hue x/y||0.4165/0.5127||Good|
|1080p/24 Cadence (IAL)||Pass||Good|
|1080i Deinterlacing (film)||Pass||Good|
|Motion resolution (max)||600||Average|
|Motion resolution (dejudder off)||600||Average|