- Written by Chris Heinonen
- Published on 13 August 2012
Sony 46HX929 46" Backlit LED-Array HDTV On The Bench
First thing, the Sony 46HX929 lost chroma resolution with a 4:4:4 YCbCr signal, but not with 4:2:2 or RGB. This is a little strange, but easily avoidable by not using 4:4:4 for a colorspace with the display. Additionally with some very fine black and white test patterns, you can get a bit of green fringing at the edges of lines. I've seen this on other sets as well, and it only occurs on certain specific 1-pixel sized test patterns, but I can't notice it with real content.
Looking at the pre-calibration numbers, most people will be quite happy with how the HX929 looks out of the box. The grayscale had an average dE 1994 error of only 3.3, with an average color temperature of 6732. Gamma was very close to our target as well, though the grayscale is a little low in green as you can see in the graph.
Color results are also very good, with almost all dE values below 3 and a luminance that was almost spot on. When we look at the luminance values from 0 to 100 we also see that it is very consistent across the whole range of intensity levels, so any level of light should be accurate.
The CMS in the HX929 isn't as full featured as I expected, but with the 2-point grayscale control I was able to really dial in the grayscale and gamma as seen in the charts. Our average dE 1994 is now below 1 and totally invisible to the naked eye, and that green error in the grayscale is now gone. The CCT of 6534 is almost the ideal 6503, and our gamma is very close to ideal.
There is no CMS for the colors in the HX929, so I had to do all adjustments using the Color and Hue controls, which meant taking the setting that had the least error, but that I couldn't dial in colors individually. The white errors are now gone thanks to the grayscale improvements, and every color but red has been improved overall. The Luminance values across the spectrum have also improved, other than red, though they did have more of an issue at 10% than before. This 10% issue can be seen in the grayscale graph where correcting the rest of the grayscale caused a blue shift at 10%, which is probably causing some of this issue. Overall the color performance is still very good, but I do with there was a CMS to really dial in the colors even more.
On our colorspace handling tests, I had the YCbCr 4:4:4 issue mentioned earlier that affects chroma, but nothing else. 3:2 and 2:2 cadences were detected correctly with all the test content I could find, leading me to decide that the issue I had with CBS Golf is more content related than display related. Cadence locks were reasonably quick and solid, so it will handle your HDTV content just fine.
This review is also a first attempt to test motion resolution using an AccuPel DVG-5000 pattern generator with the optional test patterns. Most people assume their display can always do the full resolution, but due to delays in pixel response and other factors, you often lose resolution as the speed of motion increases. To measure this, I tested with objects moving at 1, 2, 4 and 8 pixels per frame, and at both 24 and 60 frames per second. I also tested these using different frame interpolation modes available in the HX929 to see how those improve the resolution.
As we can see, the resolution drops way off as speed increases, though the motion interpolation certainly helps with that. All of the interpolation introduces artifacts that are clearly visible with test patterns, and also clearly visible when watching real content that has the interpolation applied to it. As we move to different display technologies or current ones advance, this resolution will increase, but for now it is an additional thing that we can measure in a display. How visible this is to you is a different matter entirely.