- Written by Ofer LaOr
- Published on 26 May 2008
The remote is simple and rather intuitive but also long and somewhat cumbersome. There are no direct access buttons to critical features such as discrete on/off, or specific digital connection input selection.
The bottom third of the remote opens up to reveal more functions that are mostly useful with Blu-ray players by Sony.
The unit’s menu system is quite easy, but I would have hoped for some improvements. I like the Philips self calibration features, which are missing on the Sony.
This display has an 8ms response time, which is a tad slow these days, but given that the 40" model has about 6ms of response time, it’s not that bad. Response time is how long it takes for a black pixel (i.e., one that completely masks out light) will take to transform into a white pixel (i.e., turn from completely opaque into a transparent pixel). Note that LCD pixels need to go through all the shades in between, which is often what causes a smearing effect behind moving objects.
Response time does not tell the whole tale, though. One problem of MPEG compression is that it often provides you with an initial screen that is “rough around the edges" (often containing a lot of MPEG artifacts - in particular, band marks, macroblocking, and mosquito noise). We don’t notice this as much because subsequent images correct it by making small and subtle changes to the image that resolve this problem. For example, the first image of a gradient blue sky will have a lot of banding and macroblocking. Subsequent frames correct this by refining the image and doing away with many of the artifacts. Since this process occurs constantly, it goes almost unnoticed. However, this is where an interesting parameter called “gray to gray response time" kicks in.
As an example, say we need to go from brightness level 0 (black) to level 255 (white). A typical LCD will take between 6 and 8 thousands of a second to transition between them (going from 0 to 1 to 2, to 3, etc., until it reaches full 255). However, if we have a blue sky and we need to make a very subtle change, the physical properties of liquid crystal will often resist this effect. That means it can take a much longer amount of time to transition from level 127 to level 128. In some cases, we can see that the change is so subtle that the magnetic crystals don’t have enough force to make the transition and will often stay stuck at 127. Those subtle changes that make the image look better, may very well go unnoticed by the liquid crystal, thus accentuating MPEG artifacts that should not have been visible otherwise.
To battle both problems, 100/120HZ refresh rates come into play (100Hz in Europe, 120HZ in the US and Japan). Instead of giving the liquid crystal one chance to transition between 127 and 128, driver electronics tell the liquid crystals to make the transition several times. How many times exactly? Well, that really depends on the source. If we’re talking about 60Hz normal TV content – it means that that you could have either 29.97 or 23.976 frames showing per second. That means that the driver will tell the screen to refresh itself 4 times or 5 times per frame. This reduces artifacts by allowing the frame to be portrayed accurately even when the transition from the previous frame was more subtle than the pixel can normally transition to. It also has the added effect of shortening the black-to-white response time (no more pointer trails and less smearing).