Thursday, February 24, 2011

What exactly is the smoothing problem with Samsung's 2010 and 2011 tv's?

In short: with all the digital noise filters turned off, there is still temporal smoothing of the incoming video. For example film grain isn't reproduced correctly by this unwanted smoothing. This smoothing effect can only be switched off by turning on "Game mode", which introduces other problems (no 10 point greyscale, judder with 24p film material, disables motion plus).

Here are some examples:

Unfortunately, just like last year’s midrange and top-tier HDTV models from the Korean conglomerate, the Samsung UE55D8000 still has its noise reduction feature running permanently in the background, unless the user enables [Game Mode] (more on that later). This occurs even when the TV’s noise reduction controls are disabled in the user menu. As with even the best noise reduction systems, the noise reduction causes motion artefacting: for example, with the Blu-ray Disc of Black Swan (shot mostly on fairly grainy 16mm film), the NR processing causes the actors and actresses to look as if they are wearing excessively powdery make-up which is flaking off their faces during any sort of movement. Samsung UE55D8000
Unfortunately, Samsung’s engineers apparently think of themselves as quite the cinematographers, and have seen fit to impose their own look on the picture, albeit in a mercifully subtle way. Even with all of its digital noise filters turned off, the Samsung LE40C650 still applies some light temporal smoothing to the image, which means that the texture of film grain is lessened when the image is in motion (the unadulterated image can be seen when the source player is paused). You can also disable this “feature” by enabling the TV’s Game mode (as this mode cuts out as much processing as possible), but this introduces 60hz motion judder with film material, disables the advantages of the Motion Plus system, and (less severely) means that you also lose the 10-point Greyscale correction. Naturally, we hunted at great length in the TV’s service menu to try and disable the temporal smoothing, but could find no way of doing so. Only the most observant viewers will notice the processing, but this does not change the fact that “Off” should mean “OFF”. source: Samsung LE40C650 review
During the last reviews of Samsung displays, we’ve been largely very happy with their HD performance, but were annoyed at a “hidden” noise reduction feature, which caused the natural film grain texture present in high quality video transfers to look slightly “sticky” and smeared. This occurred even with all of the HDTV’s noise reduction controls shut off, but could be defeated in the “Game Mode” (at the expense of losing 10-point Greyscale Calibration and smooth reproduction of 24p material such as films). source: Samsung LE40C750 review 
We spent a good few hours calibrating Greyscale, Gamma, and Colour on the Samsung PS50C6900 – and then almost tore our hair out in frustration when we realised that this is one of the Samsung flat-screen HDTVs which applies temporal smoothing (selective motion blur) to the incoming video – even when the [Noise Filter] controls are switched “Off”. This meant that we had to switch over to “Game Mode” to avoid this annoyance, which involved re-calibrating.
Why is this smoothing so bad? Because it has the effect of nearly, or completely removing any sort of film grain texture that is critical to the high quality presentation of film material. As well as being aesthetically wrong, this sort of processing strips definition and life out of the picture on screen. While this sort of noise/grain reduction would be appropriate for poorly lit video material, it has no place for professional 35mm films (and even 16mm films, for that matter). We did complain directly to Samsung before about this issue, which appeared to result in a firmware update which lessened the processing, but did not remove it. source: Samsung PS50C6900 review
Perhaps the most irksome 'feature' of the Samsung LEC650, is its propensity to 'smooth' the picture and in the process remove very fine details from the final image. I first noticed this effect whilst viewing an HD FA Cup replay broadcast from Elland Road, Leeds. I was actually side by side testing real world motion performance against a plasma when I noticed the pitch looked different to that displayed on the Panasonic. The plasma showed the grass was actually cut up quite badly whilst the Samsung was smoothing the nuances of the texture. I then back to back tested some Blu-rays in my collection that I knew contained a fair amount of film grain and, sure enough, the LEC650 was removing some of this also. I again checked that the Sharpness setting of 0 was correct, using test patterns and also that the edge enhancement setting was having no effect. Unfortunately, there was nothing that could be done to combat this processing and it's something of a mystery as to why Samsung would have done it.
source: Samsung LE32C650 review
Unfortunately, HD material doesn’t reach the screen entirely untouched. Just like most of Samsung’s 2010 TVs, the C9000 partakes in temporal smoothing, meaning that it attempts to average out moving details in the picture that it deems to be unwanted noise. This also results in film grain (something similar to, but not necessarily the same as noise) being smoothed over. This is bad, because it changes the look of the material and at times causes artefacting. At times, the smoothing can be barely noticeable, but it can make some films look un-textured and flat. It’s important to note that this is not a technical limitation of the television (we’d be more forgiving if it was), but deliberate revisionism on the part of Samsung’s engineers. The control here should be in the hands of the customer, especially on such an expensive display.
Because the noise reduction is motion-adaptive, it means that the amount of grain seen will vary depending on the picture content (it also means you can see the original image if you pause your Blu-ray Disc player). For example, at the start of chapter 17 of the Aliens BD, the scene is lacking its film-like texture – until a cloud of smoke rushes past the camera, which brings powdery remnants of the grain back momentarily. This is a shame, because LCD screens are especially suited to reproducing film material with grain, without any additional “tizzing” or dithering like a Plasma television adds due to its driving method. Later on in Chapter 18, the heavy grain in darker scenes cannot be fully removed by the smoothing processing, meaning that what’s left of it looks more like noise, and “swarms” and “smears” around in the dark. This scenario will please nobody: those who like to see films looking like films won’t be appeased, and those who dislike the look of film grain will probably have their attention drawn to it more. source: Samsung UE46C9000 review

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