- Written by Ofer LaOr
- Published on 26 May 2008
Normally, 120Hz would mean that film content would require a lot of repeated frames, and that brings us to the next improvement that 120HZ gives us. The main problem that 24fps content (film sources) causes is severe judder, particularly during horizontal camera pans. In the theaters, we often get double or triple framing (fake flicker that causes each frame to be blink several times before the next frame is shown), but in the home theater we are often more sensitive to the effect.
Several algorithms that closely resemble those used for MPEG compression and encoding allow modern technology to create intermediate frames that make quite a bit of sense. Several levels of this effect are available on the Sony KDL-46X3500. These levels actually determine how many intermediate frames are created (if any). Of course, this effect causes motion to become much smoother, but no video processing works without having side effects, and this is certainly no exception. The problems with this effect can first be described as “overly natural" and “unfilm-like". The effect is disturbing at first, kind of like the first drama series in the 90s induced motion onto the camera shots in order to achieve more realism. The image is disturbingly sharp and motion is disturbingly real. I had to turn this effect off several times during the test in order to rest my eyes. However, going back to a non-120Hz dfisplay afterwards caused everything to appear dramatically juddery.
The 120Hz intermediate frames cause several distinct artifacts. First, any compression artifacts will go into the processor and appear as part of the process. That means that bit-starved scenes could have smears or intermediate frames that look strange. To catch these, however, you will need a sharp eye. The second problem is caused when the system tries to make up for missing information in a particular scene. In such cases, the set will need to make up data (usually by generating a very blurry area where the missing data should have been). This causes fast moving objects to have somewhat blurry surroundings. This type of artifact will also take some getting used to.
The 120Hz algorithm has several levels. Standard mode appeared the best in my eyes, but it still generates some intermediate frames and copies frames the rest of the time. This really gives you the best of both worlds – reducing judder while retaining a minimal amount of new artifacts.
I measured the display’s contrast ratio at about 2000:1 static, which brings this display’s overall contrast ratio to around 13,000:1. This is quite staggering, although not as high as Sony’s press kits would have you believe.
The display is not particularly bright. It claims to go up to 500 Nits, but I was only getting roughly 150 max. The panel is not shiny or matt, it is somewhere in between. The viewing angle range is much better than competing products, I had no dramatic reduction of brightness even when going well off axis.
In my lab room, which is completely dark, and when the display was set to a completely dark source, I did see some uniformity issues. These are very small and would not normally impact your viewing pleasure.
Gamut coverage, interestingly enough, was actually less wide than previous Sony models I had measured. I was unable to get the display to show any extended gamut, even when I distinctly set out to do that.
The display is a bit inaccurate in its green primary and a bit short on the blue primary, but overall you get very nice REC709 coverage with it.
The display’s gamma goes up to 2.1 maximum. I would have liked to be able to ramp it up to 2.2 or even slightly higher. Throughout this range, the display stays quite calibrated. Just turn off the default (retina burn mode) Vivid mode and switch to Warm2. This will get you within 4% of D65 without having to do much more.
The first graph below is with the gamma setting off, giving a gamma of 2.1 The second one is with the gamma set to high, giving a gamma of 1.93.
Here is the Color Temperature measurement.
The RGB measurement.
And, the CIE.