dejudder

Samsung update nixes dejudder on PNC7000 TVs

After publishing a mostly positive review of the Samsung PNC7000 series on July 14, 2010, I received a couple of e-mails from readers wondering why I didn't notice its overt dejudder processing.

The processing, which apparently cannot be defeated without engaging Game mode on the PNC7000, creates a smoothing effect that typically make film look more like video. It's sometimes called the "Soap Opera Effect" at places like enthusiast Web site avsforum.

I replied to the readers that I didn't see any dejudder on the sample I reviewed, but I promised to ask Samsung for an explanation.

The explanation came a couple of days later, when Samsung's representative said the company had sent me a review sample that contained firmware that was not yet available to the public.

The reply e-mail read:

"A firmware update is being released on Friday, 7/23 (v1026) and will solve your reader's dejudder issue, updates your review unit already contains." When I asked why, the reply was: "Your TV had the firmware update because it was already supposed to be out before Friday and we didn't want you to have to re-review the unit."

Test pattern exposes more issues with dejudder processing, but does it matter?

We've often complained about the video-like look of dejudder processing circuits like Samsung's Auto Motion Plus (AMP), Sony's MotionFlow, and LG's TruMotion found on those and other companies' 120Hz and 240Hz equipped LCDs. Using a process called Motion Estimation/Motion Compensation (ME/MC), they remove some or all of the judder from 24-frame, film-based sources, producing a look some viewers prefer. For the record, we strongly prefer to leave these modes turned off.

But in addition to that videolike smoothing effect, the processing also causes further image degradation. We've documented numerous such instances, which often appear as halos, trails and other unnatural effects clearly visible in program material, especially during medium to fast movement, such as an actor turning his head quickly during a closeup.

Now a post at HDguru.com by reviewer and industry observer Gary Merson exposes additional artifacts caused by the processing. The artifacts are visible in a video of five LCD TV makers' dejudder-equipped LCD TVs (a sixth plasma TV's wedge lacks the flashing and much of the moire). They appear as unnatural flashes and tears in addition to extensive moire that looks like confused, curving lines. The test pattern in the video originated from a Blu-ray test disc by Spears and Munsil, a copy of which is included with the Oppo BD-P83.

Using a few of the 120Hz and 240Hz HDTVs I have in my lab at the moment, namely the the Samsung UN46B7000 and LN52B750, the Sony KDL-46VE5 and KDL-52XBR9, and LG 47LH50 and 47LH90, I was able to confirm the Guru's results using the Spears and Munsil disc played via a PS3 at 1080p/24. The flashing artifacts were indeed visible with the dejudder circuits turned on, and disappeared when they were turned off (the flashes and extra moire can appear subtle in the video, but in person the difference is much more obvious).… Read more

Sony flows 120Hz down to lower price points

Formerly a feature reserved for high-end HDTVs, 120Hz with dejudder is becoming more common at for less money, as evinced by Sony's 2009 KDL-V5100 series of flat-panel LCDs.

The three-size V-series includes the 52-inch KDL-52V5100, the 46-inch KDL-46V5100 and the 40-inch KDL-40V5100. Each offers the company's dejudder processing, known as MotionFlow, that we've reviewed in models such as the KDL-46W4100 from 2008. While we're not big fans of dejudder processing in general, some viewers like the smoother look, and Sony's version performs relatively well.

Other features of the V-series include 1080p resolution, four HDMI inputs, … Read more

Sharp's 120Hz LCD TV bucks blurring, but doesn't dejudder

Ah, 120Hz. Like many features used by TV manufacturers to induce people to spend more money on step-up models (see also 1080p, HDMI 3.0), its visible impact on picture quality is often difficult to discern. In test patterns, 120Hz can reduce blurring, and when paired with a 1080p/24 source it can make film-based sources appear a bit smoother, but for the average viewer, and in many cases even experienced reviewers like me, the differences appear slight.

It's easy to confuse 120Hz with dejudder processing, which can have a significant visible impact on picture quality--not all of it good, but that's another story. The confusion increases because many manufacturers market 120Hz and dejudder in the same breath, and, in fact, nearly every 120Hz LCD also features dejudder. The Sharp LC-46D85U we just reviewed is one exception.

Smoothing on LCDs--Ask the Editors

Hi David,

Based on my price range and the reviews I've read, including yours, I'm very interested in the Samsung PN50A550 and the Panasonic TH-PZ85U series. However, when I went to see them in the shop, I was very impressed with the video quality of the Sony KDL-XBR4 and the Samsung LN-T4671F. The first two are plasmas and the second two are LCDs, but I was most impressed with the smoothness of the latter two. You commented on that smoothness in your reviews and made it seem like it's a feature that can be turned on/off. Anyhow, I was just wondering if that feature is available in the plasmas I was interested in. You seemed to comment how it can be unnerving at times and it seems like a feature than can be adjusted. There isn't much of a mention of it in the Samsung A550 review and I just wanted to know if that smoothness can be turned off/on in the plasmas. Thanks, Jon

Hi Jon,

That smoothness I mentioned in my reviews is the result of a de-judder video processing mode. Pioneer put a similar mode on its 2007 plasmas, including the PDP-5080HD (pictured), but it's not as smoothing and it introduces a lot more artifacts compared with the LCDs I've tested, so we preferred to leave it turned off. More recent reviews of de-judder-equipped LCDs include the Samsung LN52A650 and LG 47LG60. To answer your original question, I don't know of any plasma TVs available now aside from Pioneer's models that have de-judder processing.… Read more