The Perfect Vision
Toshiba 46LX177 Additional Notes and Technical Ratings
Under the Hood | Adjustment Notes | Test Discs | Technical Ratings
Under the Hood
According to their web site, Toshiba’s PixelPure 3G video processor uses 14-bit internal processing for 12-bit output. However, the CineSpeed LCD panel has 10-bit output, so apparently some bits are providing “headroom” or are simply being truncated somewhere in the video signal chain.
Toshiba’s Native Mode is a “1:1 mode,” which eliminates overscanning. This is essential for optimal performance with 1080i/p signals.
Adjustment Notes
Contrast can be turned up almost all the way to 100% without clipping. (Clipping does not become apparent until you reach a setting of 99.) There’s practically no ringing regardless of the Sharpness setting. The Warm color-temperature setting was closest out of the box, though it tended slightly toward cyan/green.
The backlight was maxed out of the box, but it doesn’t need to be. Even when turned all the way down, the 46LX177 produced good white levels and excellent blacks for dark room viewing. You can easily turn up the backlight to compensate for ambient room lighting without affecting the contrast ratio. The backlight was fairly uniform, with lighter areas visible in the top corners and down both sides. The viewing angle was wide without much color shift. In fact, flat fields in general were admirably even across the screen.
On the chroma multiburst pattern from the AccuPel signal generator, there was a strange flicker visible in the 37MHz burst, but only when using HDMI.
TPV’s standard policy is to evaluate most TVs without adjusting any controls that users can’t reliably tweak themselves, and this is exactly what we did with the 46LX177. However, the green primary was so far off that we decided to see if we could improve it using the set’s ColorMaster Pro system, which provides hue, saturation, and brightness controls for each of the three primaries and three secondaries. We were able to bring the green much closer to correct using these controls, which means that a professional calibration would be a good thing to do with this TV.
Test Discs
The HQV Benchmark DVD showed good processor performance overall, though we’ve definitely seen better jaggy results. The set took a second or two to lock in to 3:2 pulldown, but it did get there.
The HQV Benchmark HD DVD’s video resolution loss test looked excellent, with no flickering. Jaggies were non-existent here. The film resolution loss test looked good in general, with a slight amount of flicker visible in the middle horizontal resolution burst. Again, the set was slow to lock in to 3:2 pulldown. The scan across the bleachers looked fine, with no obvious softening or jaggies.
Microsoft engineer Stacey Spears’ test HD DVD confirmed that Native Mode is a true 1:1 mode, with zero overscanning. The luma burst showed some flickering in the high frequency horizontal patch, just like we saw from the AccuPel. The chroma burst showed no flickering, but the vertical high frequency burst was totally rolled off.
Technical Ratings
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