Black Level & Local Dimming
The 47LM960V uses an IPS panel, an LCD panel type that traditionally does well (compared to the LCD competition) with off-axis viewing, but isn’t famed for its contrast performance.
The LG LM960V has a number of [LED Local Dimming] options: three levels of aggressiveness, and an Off switch. Turning the feature on will cause the LED lights to dim during dark scenes, and brighten during lighter ones. Of course, you can’t have it both ways: if the LEDs dim during a dark scene, you’ll make any small bright objects in that same scene less bright, because the number of dimming zones is much smaller than the 1920×1080 pixels on screen.
The other issue we found on the LG 47LM960V is that using the [LED Local Dimming] feature can cause some strange issues with high-end gamma. If the TV turns the LED brightness down during a dark scene, it’s normal that whites will get dimmer – the only way to avoid this and get true per-pixel local dimming is to buy a Plasma HDTV – but we also noticed what looked like a loss of gradation in bright areas, too. With small details like this noted, we should mention that local dimming on most LED LCDs is far from perfect, anyway.
And now, the black level measurements. In a fully darkened room with the Klein K-10 meter pressed up against the screen, we measured the unassisted black level performance – that is, a black screen taking with [LED Local Dimming] Off – to be 0.174 cd/m2, which is roughly what we expected from an IPS LCD display.
With [LED Local Dimming] engaged on its lowest and highest settings, we found that Low, Medium and High settings measured 0.033 cd/m2, 0.037 cd/m2, and 0.029 cd/m2 respectively – yes, the lowest setting is darker than the middle one. Of course, those measurements are only of a black screen and are of no use for watching actual content.
More realistically, the black patch in the middle of an ANSI test chart returned 0.169 cd/m2, 0.148 cd/m2, and 0.158 cd/m2 for the Low, Medium and High local dimming settings, and 0.174 cd/m2 with the feature turned off. Either way, don’t get caught up in the small differences – although they’re standard for IPS LCD, none of these are particularly impressive blacks.
The LG 47LM960V has a [TruMotion] feature, which has “Smooth”, “Clear”, and “Clear Plus” preset modes, as well as a “User” mode. We were interested in the “Clear Plus” mode, since this performs more aggressive backlight scanning in order to increase perceived motion clarity. The trade-off is in image brightness. Unfortunately, there’s no way to take this more aggressive backlight scanning without taking motion interpolation along with it. (Motion interpolation is generally okay for video content, but causes soap-opera like motion with films).
In fact, all of the “TruMotion” modes cause some level of motion interpolation, even the “User” mode with [De-judder] set to 0 and [De-blur] set to 10. We experimented with different settings, but all of them were performing motion interpolation, so we just shut the feature off for film content, which isn’t of a high enough frame rate to reveal many LCD motion problems, anyway. We recommend that owners try the User: De-judder 0 and De-blur 10 setting, and shut it off if they see motion artefacting.
With [TruMotion] disabled, the LG LM960V managed 300 lines of resolution – standard for LCD TVs. With the aforementioned user mode, it resolved all 1080, with some mild flickering artefacts.
Our 47LM960V review sample (picked from retail stock) featured a “dirty screen effect”, which was brutally obvious on the grey scrolling test chart on the FPD Benchmark Software disc, where small differences in brightness were visible across the panel surface.
Fortunately, actual content was much kinder to the LG, with these issues almost never appearing during film or TV viewing. It’s not impossible that they’ll crop up, though, especially with flat animated content.
SD content was handled pretty well by the LG 47LM960V. When we fed it a scaling test chart, all of the details were clear and crisp without much in the way of ringing, although the vertical resolution check was flickering slightly, indicating that the motion detection sensitivity of the deinterlacing algorithm is a little on the twitchy side. This is unlikely to pose a problem with real-world material.
Diagonal interpolation for standard-def content was good, and in real-life viewing, we saw little in the way of jagged deinterlacing artefacts.
With [Real Cinema] enabled, the LM960V had no trouble passing the 3-2 pulldown detection test sequence for the US NTSC TV system. For film transferred to PAL video, we found that it would at first correctly detect and lock onto the appropriate 2-2 test clip, but would lose its grip if the scene content changed too much – for example, if there was a fast camera movement. We’ve counted this as a “fail”, since real movie material isn’t always guaranteed to be sedate.
Even although we had [MPEG Noise Reduction] turned off, the 47LM960V appears to be cutting off high frequencies, which tones down the appearance of mosquito noise and block edges a little, but can give the image a slightly hazy look. Of course, digital TV broadcasts tend to look, well, fairly terrible anyway, so we don’t think anyone will lose sleep over this even if they object to the processing.
High Definition content could look good on the LG 47LM960V, with the excellent greyscale and colour accuracy really helping the believability of the image. We’ll talk more about these later, but before that, we need to mention several video processing issues which affect its performance.
When the 47″ LM960V first arrived with us, it featured a bug where the vertical resolution of the image would sometimes be reduced (even with 1080 progressive input). We first caught this during playback of movies on Blu-ray, where the image became blurred slightly in the vertical direction during some movement. It was easy to spot if we pulled up the disc’s menu – the (static) fine font details would alternate between clear and blurred depending on the on-screen motion. Firmware version 03.04.05 corrected this, so thumbs up to LG.
There are still some issues with the 47LM960V that users and potential buyers should be aware of, though. First of all, there’s no fault-free way to get “cinematic” motion out of the HDTV. Let’s talk about the [Real Cinema] mode. This is a combined film mode deinterlacing AND 24p output option. Turning it On should:
- Instruct the TV to correctly convert 480i, 576i and 1080i content to 1080p progressive in the best way (“film mode deinterlacing”), and
- Output 24p content without adding judder.
There are problems with point #2 (24p output). With this feature turned on with 1080p input from Blu-ray, we noticed a large amount of motion stuttering just after scene changes, and also during fast-paced action scenes. A good example is with Leon: The Professional (Extended Edition), at 4:35, where gangsters begin firing weapons (complete with bright white flashes coming from the guns). Here, the rapid movement causes frames to stick on screen temporarily – one frame from the source being repeated for two frames on the panel – presumably because some video processing circuit in the LM960V is mistaking this unpredictable motion as a scene cut. As such, we turned [Real Cinema] off and instead made do with the rhythmical, but still very tolerable motion judder, which to our eyes, was better than smooth camera pans but small skips in motion just after scene changes.
Next up, motion clarity. The LG 47LM960V, even with noise reduction (NR) turned off in the menu, sometimes partakes in noise reduction. The NR control employs temporal smoothing (where the TV’s video processor suppresses small pixel changes across multiple frames in video sequences, a trick often used in video to reduce the appearance of noise or grain). This can cause severe motion smearing, especially during dark scenes, where the processing appears to kick in more frequently. Unlike Samsung’s mild undefeatable noise reduction on its European (but not US) models – which we hope they’ll fix with firmware updates – LG’s is not constant in its application. Sometimes, all the grain in a scene will correctly come through (the 47LM960V actually passes our film grain test sequence!), but will be suppressed a few seconds later. With the Leon: The Professional (Extended Edition) BD, there’s a great example at 14:37, where the television suppresses grain at the beginning of the scene, but suddenly backs off when Gary Oldman moves and walks out of shot.
Again, this NR is taking place even with the TV’s various noise reduction controls shut off, but as we can see, the controls are not actually off. This is interesting, because it means that BOTH Korean brands (LG and Samsung) seem to have an interest in scrubbing out film grain – and with it, picture details – in their TVs.
We’re genuinely terrified that some well-meaning reviewers of Blu-ray Disc movies might be down-rating video transfers for DNR artefacts, when in fact, the culprit is in-TV processing. Users should be able to trust that Noise Reduction: Off actually means “Off”, but the sad truth is that some brands, time and time again, can’t be trusted to provide an untampered-with image. We really hope they can address this sort of tampering with firmware updates.
We did try labelling the input “PC” to get around the video processing, but this didn’t help, as it has done in the past. What did help though was selecting the “Game” picture mode, which kills this processing. This does lock out access to the advanced calibration controls and other functions, so isn’t really that great a solution. It does, however, show what the LG 47LM960V is potentially capable of.
Korean TV manufacturers need to learn that film grain isn’t a defect in the picture – it’s just the texture of the film. In a calibrated display with the Sharpness controls correctly set, the levels of grain found on most Blu-ray movies won’t be obtrusive, and will give the film texture and extra detail. The smearing artefacts that result from trying to remove it – especially with in-TV processing – aren’t pretty. Japanese TV makers, who often have close connections with Hollywood (Panasonic owns a Hollywood compression and authoring facility; Sony owns an entire film studio) have demonstrated that they understand this already – Korea appears to have some catching up to do.
We did try enabling 60hz output (rather than 24hz) from the Blu-ray player, to exhaust all potential ways around this, but the LM960V’s behaviour remained the same. The only way to avoid the NR is to use Game Mode, which we don’t really recommend.
With all of that video processing discussion out of the way, let’s move onto the colour science (which is an area where LG typically do a good job, thanks to their frequent inclusion of calibration controls) and contrast discussion. We mentioned that the picture was slightly beige-tinted before calibration, but thanks to the comprehensiveness of the 20-point greyscale calibration controls, and also the largely accurate colour tracking, content looked appropriately coloured with nearly no visible tinting. The Blu-ray Disc of Babel – despite using the aged MPEG-2 video codec, and having a few small compression artefacts as a result – still looks outstanding in terms of filmic detail, and the LG presented the desert scenes in Morocco with the right tone, really letting the warm feel come through. Skin tones, skies, and other memory colours, all looked correct and untinted.
The 47LM960V uses the passive 3D technology, which LG are probably the biggest backers of, under the name “Cinema 3D”. Compared to active-shutter 3D, nearly everything about the passive system is good news: the glasses are ultra-cheap, lightweight, they don’t have to sync with the 3DTV, there are no batteries to charge, the images are usually brighter, and there’s no flicker. The catch is the vertical resolution, which is essentially halved, since half of the lines on the panel are dedicated to showing the left eye image, and the other half, the right eye image.
The resolution of passive 3D has become a contested topic, with some sides claiming that its 3D images really are as good as “Full HD”. LG have done this in the past. The argument goes that areas of the image which have little difference between the two eye views will be presented in nearly-as-good-as full resolution, because only a small offset is needed to produce a 3D effect (in fact, too big a difference between the two views can cause discomfort or even sickness). It’s a fascinating subject, and in our opinion, the theory is quite sound – provided you’re watching the 3D TV with the glasses off. It’s clear as day when you put them on that the image appears with dark horizontal lines visible.
Even if the theory was correct (and we welcome input on it), we can put it to bed in the context of the LG 47LM960V, because we discovered that its video processor vertically softens extra-dimensional images before they hit the panel, anyway – something we confirmed with our own 3D test patterns. Why would it do that? Presumably to avoid sharp edges in the picture interacting with the natural resolution limitation of the passive 3D display, and causing excessive moire interference or jagged edges. LG have a lot to be proud of with passive 3D, but the fact that they’re vertically filtering images in this way sort of contradicts their claim that the system is “3D Full HD”. To their credit, nowhere in the specs do LG make this claim (although they’ve made it before), instead using the “Cinema 3D” branding. That’s not to single out LG, either – our testing has found that Panasonic’s “Full HD 3D” Plasmas are, in truth, only close to Full HD 3D. The other thing to note is that the black lines over the image isn’t just dark, but they’re thick, too. In fact, the vertical pixel aperture is greatly reduced because the lines are taller than the active pixels. It truly is the Achilles’ heel of passive 3D.
Moving away from resolution discussions, the LG 47LM960V passed all of our 3D motion judder tests with flying colours. Due to the design of the passive 3D system, we weren’t surprised to see the same level of performance in the third dimension as we witnessed with the 2D display mode. 50hz, 60hz and 24hz inputs all played back perfectly, without any motion judder or undefeatable frame interpolation features. The LM960V presents cinematic 3D motion in this regard. Keep in mind though that we saw issues with 24p motion during the 2D High Definition assessment, and it’s very possible that we’d have seen the same issues in 3D if we had had content that happened to reveal it.
Viewing actual tri-dimensional content reminded us of the many strengths of passive 3D. We could enjoy 3D for hours without anything approaching dizziness or tiredness, due to the flicker-free nature of the glasses. The 3-dimensional effect was excellent, with minimal crosstalk. Despite the calibration difficulties, Greyscale tracking and colour were very accurate for the most part, allowing for 3D image that was free of tints (after calibration, that is).
For completeness, we should mention that once, when we viewed a 3D Blu-ray (frame-packed) source, there was some obvious jaggedness in the horizontal direction. This went away when we switched inputs, and then back again, and we never saw it since.
In the default configuration, we’re not exaggerating when we say that fast-paced or first-person shooter games are borderline unplayable on the LG 47LM960V. Fortunately, there are two ways to reduce input lag and make video games more enjoyable on this TV. The first is to use the “Game” picture mode. The other is to label the input “PC” in the INPUT selection screen by highlighting the appropriate HDMI input and pressing the Red button. There is also a “Game” label which changes the performance again. Us being us, we also tried combining all these methods, just in case there was any way to speed up video processor response time.
Input lag was close to 100ms(!) in some modes, even in the dedicated “Game” one, but we managed to shave this down to 67ms by labelling the input “PC” and by selecting the “Game” picture mode within that. This still isn’t great – Panasonic’s ST50 Plasma this year manages a buttery-smooth, ridiculously enjoyable 16ms – but it’s an improvement, at least. The fact that the “PC” mode is faster than the “Game” one suggests that LG don’t really understand the need for low input lag with gaming.
Sometimes, readers will ask us, “why do you say nothing about sound quality?” – and our reply is that most flat-screen TVs have just about “workable” sound, and anyone who wants to enjoy films will invest in a separate audio setup. We only comment on audio quality if it’s noteworthy. Such is the case with the LG LM960V. It does an exceptionally good job of providing weighty, if slightly “boxed in” audio. During louder action films, we did have to enable the [Sound Optimizer] feature to avoid bass distortion. However, the sound is excellent – by flat-panel TV standards.
LG are on to a winning user interaction device with their Magic Remote. Although it’s nonsensically styled in gloss black (meaning that it looks greasy and finger-printed after a few minutes of usage), it fits very comfortably on the hand and is the best user interface device we’ve used since the computer mouse. A cursor appears on screen, and using it to navigate around web pages and some TV menus is very intuitive. It’s the first time we’ve found ourselves actually wanting to use the web browser feature on a television – in fact, we wished we could use it to navigate our Blu-ray test discs!
Like with most recent LED LCD televisions, the most remarkable thing about the LG 47LM960V is its styling. LCD picture quality seems to have peaked, with the main advancements being made in internet-connected functionalities and aesthetics. The LM960V does well in these areas: the display’s rounded edges, silver trim and basically non-existent bezel mean that it’s going to turn many heads, and the addition of the Magic Remote means that the web browser on the TV is something that you’ll actually want to use. There is also an exhaustive array of calibration controls (and we mean “exhaustive” in every sense of the word!), which allow the HDTV’s overall accuracy to be brought up to an excellent standard.
As for picture quality, the performance was basically as we had expected from an LG LCD product using an IPS panel. Overall picture quality can be good, with the IPS strengths of better-than-typical LCD viewing angle performance and little in the way of panel-generated motion artefacts being present. However, the Korean conglomerate has seen fit to program quite obvious noise reduction into the video processor which squanders the latter strength of the LCD panel, and introduces smearing into Blu-ray Disc movies, particularly during dark scenes. Contrast performance is what we expected from an IPS LCD, and while the Local Dimming feature improves the perceived black levels, it can obviously dim white areas in dark scenes.
The 47LM960V also isn’t a great display for video gamers, with an unusually high amount of input lag slowing down gamepad-to-screen responsiveness, even in the “Game” and “PC” modes.
With the negatives out of the way, though, there’s still enough left about the LG LM960V to like. While its out-of-the-box Greyscale accuracy wasn’t great, users who have a means of calibrating the television will find that the incredibly comprehensive 20-point Greyscale control – while a real kludge to use – is worth perservering with, because it brings about basically perfect Greyscale accuracy at nearly all brightness levels. Colour accuracy, while imperfect, is also of a high standard. For users without external speakers, it also produces some very satisfying sound. The usage of the passive 3D technology brings with it the ups (flicker free 3D, cheap, light, plentiful glasses…) and downs (half vertical resolution), and we think passive 3D, while as flawed as the also imperfect active-shutter system, fills an important gap in the marketplace.
The end result of all of this is a qualified recommendation. The competition is incredibly strong, and LG can’t afford to keep shooting themselves in the foot with video processing hiccups. Once again, LG: please, please, please make sure that these quirks don’t cross over to your upcoming 55″ OLED TV – that would be a fairly heartbreaking situation. If you’re into passive 3D, excellent design, weighty sound and a very usable Smart TV feature set, and aren’t as choosy when it comes to image quality, then give the LG 47LM960V a look.
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