- Written by Stephen Hornbrook and Chris Heinonen
- Published on 06 June 2012
Toshiba 50L5200U LCD TV On The Bench
The 50L5200U has five different picture modes: Standard, Dynamic, Movie, PC, and Preference. With any of the first four, all of the controls are available to use but when you adjust any of the advanced settings, those changes are made to the Preference mode and it changes the modes automatically without telling you, so be aware of this. All adjustments were done in the Preference mode because of this. If you aren't going to use preference mode, Movie mode was the most accurate, and some of the other modes had a color temperature of over 20,000K.
Using the Warm 2 color preset and the default Gamma, we see that our grayscale skews heavily towards blue, and we have a gamma of close to 2.0 and not our 2.2 target. With a color temperature of almost 9000K and a dE over 10, the errors in the grayscale are clearly visible to the naked eye.
Our colors are actually pretty good except for Cyan, which is way off with the dE94_Hue being off the charts. Given how bad the grayscale was, this is actually much better than I expected it to be, and hopefully we can fix the Hue using the available controls later.
New to this review are measurements for different levels of saturation and intensity. Typically we only have one point measured for reviews and rely on visual observation to see if the rest of the color points seem correct, but now we can measure luminance at 10% increments and saturation at 20% increments. Luminance values are pretty good, with the exceptions of White and Cyan that show serious errors. Saturations are much worse, with only 100% saturations being good. Since the initial color image is calculated at 100% saturation, 75% luminance that is why we see good color dE values, though as we can see they really are only good at 100% saturations.
The 50L5200U has very few controls available for calibration, with a 0.67-point grayscale (Blue and Green gains, no Red, and no cuts), a gamma control, and just your basic color and tint controls. Additionally the menu system is a bit annoying as it is in the middle of the screen and can't be moved for doing adjustments. Once it was totally off the screen the readings would change slightly, and I'd have to adjust them again, hide the menu, and measure.
These results were quite surprising to me with the lack on controls. Bring the gamma down to -2 made a huge difference, and then it was using the white balance adjustment to try to even out as much of the grayscale as possible. The dark areas of the image still have a tint to them, being a bit greenish or bluish, but there was nothing more I could do to fix that. Overall the gamma is very close to 2.2, and the average dE for the grayscale is very low across the scale. If Toshiba had added full 2-point grayscale control, that average dE probably could have been brought down below 1 but this was what we had.
The color measurements were significantly affected by the grayscale corrections, and then it was just adjusting color and tint to bring the luminance levels into line as well as the hue. Our largest error is with blue, exactly where we want it to be, and every other color now measures below 3 dE94, so it shouldn't be visible with actual content.
Our luminance readings were previously good with the exceptions of Cyan and White, but those now have been brought down to the point that blue is our largest issue, and it only hovers between 3 and 5 dE94 at the various luminance levels. This is very nice and shows that the gamma is consistent across all colors. The big improvement was with the saturations, where we previously had a lot of readings that were off the charts, now only blue poses much of an issue. These aren't quite reference quality results, but they are much better than I expected from the initial readings and the controls available.
The 50L5200U handled all colorspaces well, though I did think there was a bit of extra sharpening being applied on some of the patterns I looked at. This was visible in both motion and still images so I don't think it's an LCD motion resolution issue, but just that Toshiba was adding a little extra sharpness to the image even with the control set to 0. The test pattern that the Toshiba did not do well on was the Jaggies test. With the ship it was clearly visible on thin cables and lines that there was very little smoothing going on, and jagged lines were very present. These were also easy to notice in the mixed cadence testing, but since we are concerned with the cadence locks there and not jaggie reduction I didn't deduct for it. I would feed the 50L5200U 1080p content whenever possible to avoid the aliasing that was easy to see on 1080i content.
Over component video the performance was nearly as good. The highest resolution multiburst patterns for both luma and chroma are missing details, but that is almost always the case with component video. The main notes I found with component is that the jaggies issue is still there, but inside the advanced features you can choose between video or film mode, and you need to have film enabled to do 2:2 or 3:2 pull-down correctly. It would be nice to have an Auto option there, but as it is you might need to manually chance this depending on if you are watching TV content or Film content and want the full resolution.
I did notice that the backlighting system was a bit uneven. Calibrated to 40 ftL in the center, I measured 40 ftL at the left and right edges as well, but between the sides and center, the light output could easily drop to 30-35 ftL, which was visible both with test patterns and on some content. There are also bright corners that are easily visible with letterboxed material.
With DynaLight Off, I measured a contrast ratio of 2,832:1 with 41.091 ftL on a white screen and 0.015 ftL on a black screen. Turning on DynaLight let the black level reach 0.002 ftL, which was just light contamination from other sources possibly. Since this was a pure black screen that let the TV disable all the LEDs, I tried this with an ANSI Contrast pattern, and while my ANSI results can't be 100% accurate, the results were identical with DynaLight enabled or disabled. I also played with the dynamic contrast control but found that it crushed shadow detail when engaged, so I left it off.
Overall you can coax a good image out of the 50L5200U with a calibration, despite the small amount of control available in the menus, though most of the extra features are best left disabled as they made no appreciable benefit to the image or made it worse.