Sony EX645 review:

Sony EX645

Picture quality

For the price, the Sony EX645 puts in a good performance. While the Vizio M3D0KD is a better TV overall, the Sony delivers a tidy picture with better-than-average black levels. Color depth and saturation are excellent, even if some others are able to deliver more vivid tones. Shadow detail isn't as fine as on other TVs we compared, but the trade-off of an inkier background is worth some loss of fidelity in murkier areas. The TV also showed some issues in the uniformity department, where I detected some uneven backlighting and dirty-screen effect, but it wasn't terrible.

Click the image at 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)
Sony KDL-55HX750 55 inch, edge-lit LCD
Vizio M3D550KD 55-inch, edge-lit with local dimming
Sony KDL-55HX750 55-inch, edge-lit LCD
Samsung UN60ES6500 60-inch, edge-lit LCD
Sharp LC-60LE640U 60-inch, edge-lit LCD
Panasonic TC-P55ST50 65-inch plasma

Black level: In bright scenes, it's hard to tell the difference between most well-set-up TVs, but give them a challenging dark scene like "Creation" (chapter 4) from "The Tree of Life," and differences leap to the eye. This scene is quite difficult for LCDs in particular because it involves colored wisps moving against a black background. The EX645 was no exception, showing lighter black levels than the Vizio and the ST50, but it outdid the Samsung ES6500 and the HX750 and looked very similar to the Sharp.

One strike against the Sony was its slightly less-than-perfect rendering of shadows. After the Romulan spaceship passes at the start of chapter 8 in "Star Trek," you see the antagonist, Nero, lying on a green surface. On the other TVs you could see more of the green pattern in Nero's shadow, but on the Sony EX645 it was a little smudged, though at least it was darker.

Color accuracy: While it's not possible to dial in color on a Sony to the extent you can on an LG or Samsung, the color reproduction of the EX645 was quite respectable. Whether it was the deep greens of the trees and baby nursery in "The Tree of Life" or the child's subtle blue jumpsuit, the colors of the Sony seemed more natural than most of its competitors', with the exception of skin tones, which looked a little bluer than on the other sets. The Samsung E6500 was better in terms of skin tone, with a much rosier, healthier-looking -- though still emotionally depressed -- Brad Pitt. Overall, I found that while it didn't show the most accurate color, the Sony was better than most in the more important area of color saturation.

Video processing: Sony has built itself a fine reputation on its video processing and the EX645 continues the company's good work. The TV was able to play back our 24p test scene from "I Am Legend" without any trace of judder, and it also passed our synthetic 1080i deinterlacing test as well.

As I'd expect from a 120Hz TV, the EX645 achieved around 600 lines of moving resolution. As usual to get it to do so meant activating one of its smoothing (dejudder) settings, but I preferred to leave those off.

Uniformity: Perched between the Samsung ES6500 and the Sony HX750, the EX645 was the best of the three in terms of uniformity. The other two TVs had some real issues with backlight clouding and spotlighting in the corners, and while the EX645 was better, it wasn't immune to these problems. There was some spotlighting of the backlight, but it wasn't as noticeable as on the other two. If you want immunity from these problems, look to the Panasonic ST50 plasma or the Vizio M3D0KD with their gorgeous black screens.

One issue that the TV did exhibit was "dirty-screen effect," whereby the backlight structure was visible as darker vertical lines on gray or white screens. If you watch a lot of ice hockey, you might find this distracting.

Off-axis viewing of the EX645 showed a desaturation of color and an even greater blueness to blacks, but this is a common problem of LCDs -- especially at this price.

Bright lighting: Tradionally LCDs perform at their best when in a lit room, but the Sony did have some issues. In a lit room, a black scene looked off-blue in the corners, but the EX645 wasn't alone here: it was the same with the HX750 and Samsung 6500. If you want true black, then you need to go for the Vizio M3D. The Sony has a semimatte finish and wasn't particularly reflective -- about the same level as the other TVs.

Geek Box: Test Result Score
Black luminance (0%) 0.0139 Average
Avg. gamma 2.1597 Good
Near-black x/y (5%) 0.2705/0.2679 Poor
Dark gray x/y (20%) 0.3141/0.3315 Good
Bright gray x/y (70%) 0.3125/0.327 Good
Before avg. color temp. 10034.9337 Poor
After avg. color temp. 6479.0542 Good
Red lum. error (de94_L) 2.9833 Average
Green lum. error (de94_L) 1.2529 Good
Blue lum. error (de94_L) 5.8093 Poor
Cyan hue x/y 0.2308/0.3366 Average
Magenta hue x/y 0.321/0.1439 Good
Yellow hue x/y 0.4322/0.4954 Poor
1080p/24 Cadence (IAL) Pass Good
1080i Deinterlacing (film) Pass Good
Motion resolution (max) 600 Average
Motion resolution (dejudder off) 320 Poor
PC input resolution (VGA) 1,920x1,080 Good

Sony Kdl 46ex640

What you'll pay

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