- Written by Chris Eberle
- Published on 03 October 2011
The Toshiba 55SL417U 55" Edge Lit LED LCD HDTV On The Bench
Equipment used: EyeOne Pro spectrophotometer, CalMAN Professional 3.7 analysis software, Accupel HDG-3000 signal generator, Oppo BDP-83 Blu-ray player in Source Direct mode, Spears & Munsil Benchmark Blu-ray disc.
Color is quite good out of the box with only small deviations from the Rec 709 standard. While the color points are pretty close, luminance is more visibly off, which makes a greater difference in perceived color accuracy. Since some colors are too bright and some not bright enough, the Color control alone won’t help the situation.
Pre-calibration grayscale is not too bad with only slightly visible errors on the TVs warmest color temp setting. In fact, it compares favorably with many THX-certified displays I’ve measured. Gamma is a bit dark at the low end which affects shadow detail and mid-tones up to about 50-percent brightness.
After adjusting both white balance and the color management system, color is noticeably better. The CMS doesn’t let you move the primaries but I was able to get luminance almost perfect. Secondaries are also near-perfect.
When I can’t get a display’s color points lined up perfectly, I re-calculate the gamut compensating for the inaccurate primaries to check the positions of the secondaries. As expected, they line up perfectly on the SL417U.
Grayscale turned out very well. In fact, it’s some of the best tracking I’ve seen from any LCD display. Even though Toshiba only offers a two-point white balance adjustment, the results show a 10-point system is unnecessary. Gamma flattened out a little to a much better average of 2.3 with only slight darkening in the lower end of the luminance scale.
If you want to use the DynaLight control to activate the LED dimming feature, you will affect the gamma performance negatively. While it doesn’t skew the curve wildly like some displays, it will crush detail at the low end. It also lowers overall light output by around 50-percent. The set has excellent contrast without this feature so I recommend leaving it off.
Video processing was mostly excellent except for the failure in the above-white and below-black tests. If you use a source that outputs RGB Video the full-range signal will be displayed if you set RGB Range to Full. The TV also failed the 2:2 pulldown test but this is quite common and won’t impact picture quality.