Whilst LG are not alone in their support of passive 3D - Toshiba, Philips and JVC have all recently announced passive 3D displays of their own - they are certainly the most vocal. LG do actually offer active shutter 3D in conjunction with their plasma displays but they clearly feel that passive offers 3D’s best chance of mass market acceptance. The passive 3D system uses a polarised filter on the front of the screen and a pair of circular polarised glasses that are similar to the ones that are often used in cinemas. In fact it is this familiarity with the passive system used in many movie houses that led LG to rebrand their passive 3D displays as Cinema 3D in the hope that consumers would make that connection. The 2011 line-up of Cinema 3D displays were first announced at CES back in January and last month LG held the European launch in Paris.
There are certainly benefits to the passive approach including brighter flicker free images, far less crosstalk and cheaper glasses but there is also one major drawback - resolution. In order to create the left and right eye images the display uses a polarised filter on the front of the screen and an interlaced image that uses half the lines for one view and half for the other. Thus the passive approach creates two 540p images - one for each eye - as opposed to the active approach which creates two 1080p images. In their marketing LG have been claiming that Cinema 3D creates a 'Full HD' image in 3D which clearly just isn't true and in associating their displays with the cinema they are being slightly disingenuous because while the cinema generally does use the passive system the images themselves are 1080p for each eye.
When AVForums reviewed LG's passive 47LD950 last year we found that the loss in resolution really didn't matter at any sensible viewing distance and that overall the 3D experience was very pleasant and in many ways preferable to the active displays that we had reviewed. Unfortunately the display itself had certain technical limitations and was lacking in a lot of features but we thought there was potential and were thus looking forward to LG's 2011 line-up. Finally they are here and the LG 47LW550T is one of the first Cinema 3D displays released in the UK so needless to say we were keen to find out what improvements LG had made from last year and how good the picture was in both 2D and 3D.
Styling and Connections
The black gloss bezel is quite narrow and measures 3cm at the top and sides and 6cm at the bottom. This isn’t as narrow as the incredibly thin bezels found on some displays this year but that isn’t necessarily a bad thing as in our opinion a 2D image actually benefits from having a dark border. There is also a 1cm clear plastic strip along the outer edges of the left and right hand side of the display. The 47LW550 uses LED edge lighting which makes the chassis depth of 3cm surprisingly large when compared to some of the competition, perhaps this is due to the addition of the polarising filter. One interesting possible side affect of the polarised filter was that the screen didn't suffer as much from reflections, especially when compared to displays that use a single sheet of glass.
The remote control is similar to the design used last year but it has undergone some minor refinements that result in quite an attractive looking device. Overall the remote has a very pleasing ergonomic design, it is comfortable to hold, intuitive to use and has buttons that are sensibly laid out. As well as all the standard buttons that you would expect to find on the remote there are some new ones including a Home button that provides access to the Home page and a button called Premium that gives access to the SmartTV content. In addition there is a dedicated 3D button as well as LG’s Q.Menu button that brings up either a shortcut to the key 2D or 3D menus. LG also separately sell their Magic Motion remote (AN-MR200) which is similar to the controller on a Nintendo Wii and can be used to navigate the SmartTV functions.
Menus and Set Up
Once the Setup menu has been accessed there are various sub-menus including Setup, Picture, Audio, Time, Lock, Option, Network and Support. The Setup sub-menu allows the user to tune in, set up and edit programmes for the EPG. The Audio sub-menu includes controls for setting up the sound mode, effects and volume level. The Time sub-menu sets up the time, the date and controls the timer feature. The Lock sub-menu locks or unlocks channels and programmes. The Option sub-menu customises the general settings whilst the Network sub-menu allows the user to set up all the network connections. Finally there is the Support sub-menu which includes a Software Update control and some picture and sound tests.
Within the Picture there are standard controls such as Contrast, Brightness, Horizontal and Vertical Sharpness, Colour and Tint which can be accessed from all the presets, as well as a Picture Reset function.
In ISF Expert1 or Expert2 there is also the Expert Control option which gives the professional calibrator access to an impressive array of picture controls. There is a Dynamic Contrast which seeks to boost the contrast ratio by changing the Brightness and Contrast controls on the fly and is best left off. There are also Noise Reduction and MPEG Noise Reduction controls but we found they didn't really improve the picture and were best left off. The Black Level function can be set to Low or High depending on preference and the Real Cinema function controls the deinterlacing of film based material and where possible should always be left on. The TruMotion 100Hz control activates the frame interpolation function and has a choice between Off, Low, High and User. As the name suggests, the LED Local Dimming controls the 16 LED blocks that illuminate the screen. The Colour Gamut offers a choice of Standard and Wide as well as industry standards like EBU, SMPTE and BT709. Finally the Edge Enhancer acts much like a sharpness control and just like most other sharpness control it should be left off.
Finally within Expert Control there is a Colour Management System (CMS) that should allow us to accurately calibrate the Colour Gamut. In the CMS that LG has built into the 47LW550 there are controls for the three Primary Colours (Red, Green and Blue) and the three Secondary Colours (Cyan, Magenta and Yellow). The actual controls are Colour which sets the saturation and luminance and tint which sets the hue.
Since the 47LW550 is a 3D display there is also a menu dedicated to the 3D settings which can be accessed via a button on the remote but it will also pop up when the display detects a 3D signal. This menu allows you to choose between the different 3D delivery systems including 2D to 3D conversion, side by side, top and bottom, checkerboard and frame sequential. There is also a control for adjusting the depth and viewpoint of the 3D effect when converting from 2D to 3D.
The 47LW550 also has a built-in FreeviewHD tuner that is easy to setup and includes an EPG that is both sensibly laid out and easy to use. Our only complaint would be that it doesn't include a window for the channel you are currently on. There is a recording and timer functionality that can be used in conjunction with an external HDD that can be connected via one of the USB sockets, although this has apparently been disabled in the UK. This might be the reason that there is no window because this will use one of the tuners and thus could interfere with programmes that are being recorded.
Finally you can connect a digital camera, MP3 player or flash memory through the USB ports and then access the multimedia content via Smart Share on the Home dashboard. The 47LW550 also includes DivX HD and is DLNA compliant for streaming content.
Unlike many other LG displays the 47LW550 doesn't have a THX mode so for this test we chose the ISF Expert1 mode which should represent the most accurate of the pre-calibrated presets. We also chose a Colour Temperature of Warm, a Gamma setting of 2.2 and the BT709 Colour Gamut. We selected Just Scan to ensure we weren't introducing any unwanted scaling and turned off the Energy Saving function and any other 'enhancement' feature. We set the backlight quite high in order to compensate for a slight perceived dimming caused by the polarised filter. Using a PLUGE pattern we could see that the best Brightness setting was 52 for our viewing environment and we set the Contrast control to 80. We found that leaving the Sharpness controls set at 50 resulted in an image that was free of any unwanted ringing or softness and we also left the Colour setting at 50 and the Tint at zero.
As with the greyscale performance, the out-of-the-box colour gamut is also very accurate for a preset. The CIE chart shows that the coordinates for all three primary and all three secondary colours are very close to where they should be for Rec.709. There is an error in the Hue measurement for Red, an error in the Colour (Saturation) of Yellow and the Luminance (Brightness) of Green is undersaturated but overall the errors are all below three and most are below two which is excellent. We should be able to use the CMS to tidy up these minor errors and produce a reference colour performance.
Given that the greyscale performance was already very good it didn't take long to dial in a reference performance using the White Balance controls. As you can see on the above graph all three primary colours are now tracking at exactly 100 which results in errors of less than 1 which is essentially perfect. The Gamma Luminance remains spot on and the Gamma itself is still tracking at our target of 2.2. This is a reference performance and results in a smooth transition from white to black without any discolouration.
Any image depends on an accurate greyscale because if there are any errors in that then it will affect the colour accuracy of the rest of the image. Although the colour gamut was already very good it was immediately improved by the calibrated greyscale performance, with the colour of white now measuring at exactly D65. We could then use the built-in CMS to fine tune the colours and remove any errors. Whilst LG displays do include a CMS that controls both the primary and secondary colours, they don't control all three colour axes (Hue, Colour and Luminance). On an LG display you can control 'Colour' which is a combination of Colour and Luminance and 'Tint' which is equivalent to Hue. It is a shame that LG still haven't included all three controls on their 2011 CMS but given the overall colour accuracy it isn't a major problem. As you can see from the CIE chart above the colour performance after calibration is now excellent. Any errors in Luminance would be especially obvious but they now measure less than one which is superb. There is still a small error in the colour measurements of Blue and Yellow but neither of these are visible in actual viewing material.
As usual we started with our PAL and NTSC HQV benchmark discs and first of all we checked the SMPTE colour bar test which the 47LW550 easily passed, correctly scaling the full 576i and 480i images without any loss of detail or unwanted ringing. The 47LW550 also scored well when it came to video deinterlacing with jaggies only appearing when the line was at an acute angle in the first test. In the second test the motion adaptive deinterlacing was also good with slight jaggies only appearing on the bottom bar of the three moving bars.
The 47LW550 performed well in the film detail test and correctly locked on to the image resulting in no aliasing. In the cadence tests the 47LW550 also correctly detected both the 2:3 (NTSC - USA/Japan) format and the 2:2 (PAL - European) format. The 47LW550 also correctly displayed film material with both horizontal and vertical scrolling video text, correctly displaying the words without any blurring or shredding.
The 47LW550 performed very well in all of the tests on the HQV and Spears & Munsil Blu-ray discs using high definition content. With the player set to 1080i the display correctly deinterlaced and displayed both the video and film resolution tests (provided the aspect ratio is set to Just Scan) and showed good scaling and filtering performance as well as good resolution enhancement. The 47LW550 also had no problems in showing video text overlaid on film based material and also handled 24p content without any problems, even the tortuous wedge shaped test on the S&M disc.
Using the S&M disc we checked the headroom performance of the 47LW550 from reference white (video level 235) up to peak white (video level 255) and it was very good with absolutely no signs of clipping. In addition the 47LW550 also correctly showed detail down to a video level 17 and reference black below that to video level 0.
The 47LW550 has 100Hz TruMotion and using the FPD Benchmark Software disc's scrolling resolution chart it measured around the 300 line mark without TruMotion enabled. Whilst motion handling is an inherent weakness in the technology, this isn't as good as the performance we've seen from LCD screens produced by some of LG's competitors. Things improved a little with TruMotion set to Low and when set to High the motion resolution improved to about 600 lines which is pretty good. Unfortunately activating the TruMotion function results in the dreaded 'soap opera' effect so we would recommend leaving it off.
If there is one area where the 47LW550 really struggles it is in terms of the input lag measurements. The best result we could get was an input lag of 90ms in Game mode and this is very poor when most of the displays we have measured recently have been below 40ms. On previous LG displays we had managed to reduce the input lag by using the expert modes but not this time, neither were we able to improve the measurements by naming the input as PC. To be honest the whole point of a Game mode is to have a preset that is optimised for gaming and keeps the input lag to a minimum, if you have to result to a workaround then that defeats the whole point of having a Game mode. Since posting this review LG have released a firmware upgrade that appears to reduce the input lag to 50ms in Normal mode and 25ms in Game mode. These are much better numbers and if accurate make the 47LW550 an ideal display for 3D gaming - we will confirm these measurements in a future review of an LG LCD display.
The 47LW550 uses LED backlighting which means that its energy consumption is very efficient. Using a full screen raster we measured 35 Watts at 0IRE, 65 Watts at 50IRE and 75 Watts at 100IRE in its calibrated mode. When watching actual material we measured an average usage of between 75 and 80 Watts. This is an excellent set of results and just goes to show how energy efficient modern displays have become. There are also various energy saving features but these tend to be detrimental to the image and given the display is already incredibly energy efficient they are best left off.
Picture Quality - 2D
One of the big concerns with 3D displays using passive technology is that the polarised filter over the front of the screen might affect the 2D picture performance. Based upon our measurements and from viewing actual material we found that the filter did not appear to adversely affect the 2D image. The greyscale and colour gamut were excellent out-of-the-box and reached reference standard after calibration. The only area where the polarised filter appeared to have any effect on 2D images was in brightness but since the 47LW550 is an LCD display this could be easily addressed with the backlight control.
The built-in Freeview HD tuner produced a very nice picture despite the limitations of compressed broadcasts and the excellent video processing no doubt helped with standard definition broadcasts. When it came to high definition broadcasts the 47LW550 was able to produce finely detailed and wonderfully accurate images that were a pleasure to watch.
The superb video processing and image accuracy also paid dividends when watching DVDs and the resulting images reminded you how good standard definition can actually look sometimes. However it was when the 47LW550 displayed high definition images from a Blu-ray that the performance really shone and you appreciated how important image accuracy is for a display. Watching high definition material that we are familiar with we could see that the images had an accuracy and level of detail that resulted in a very enjoyable viewing experience.
The image isn't perfect of course and there are areas where the 47LW550 could have performed better. As previously mentioned the 47LW550 doesn't handle motion quite as well as some of the competition but given that motion handling is always a problem with LCD we didn't find this limitation to be a problem. You could engage the 100Hz TruMotion to improve the motion handling and whilst this might be an option for sport we would recommend not using it in conjunction with film material.
The use of LED back lighting might result in more accurate colours, better power consumption and a thinner display but it often also results in a very uneven backlight. Whilst the 47LW550 did have lighter edges due to the positioning of the LED lights at the edge the overall uniformity of the backlight was actually quite good and didn't suffer from the clouding that affects some other displays.
The one area where the 47LW550 struggled was in black levels and whilst we didn't expect inky blacks from an LCD there have been some large improvements in this area over the last year. The 47LW550 could produce a reasonably bright image and also maintain shadow detail but the dynamic range suffered because of the lack of deep blacks. There are ways of addressing the black levels, one of which is to set the Black Level control to Low but in doing so you might lose some shadow detail. The other alternative is to use the LED Local Dimming which does improve the black levels but in doing so introduces haloing that is very obvious around white credits on a black background.
However these minor niggles aside the 47LW550 was capable of producing a very pleasing 2D image and dispelled any concerns we may have had about the affects the polarised filter may have had on picture performance.
Picture Quality - 3D
There was a bug in the software of last year's 47LD950 that resulted in the display initially failing to lock onto 3D blu-rays correctly, to fix this problem you needed to turn the 3D off and then on again. Thankfully the 47LW550 had no such problems and the display locked onto 3D content no matter what he source - be it 3D broadcasts, 3D games or 3D Blu-rays. As with the 47LD950 before, we were very impressed with the 3D performance of the 47LW550 and once again we found ourselves preferring it to active shutter 3D. The images seemed brighter and the lack of flicker resulted in a much more comfortable experience with no sense of eye fatigue. There was an immediacy to the 3D that made it both fun and exciting and far less formal than the more complex processes involved with active shutter systems. We have a reasonably large collection of 3D Blu-rays and no matter what we watched the 3D had a wonderful sense of depth and detail and despite our earlier reservations over the 47LW550's ability to handle motion there were never any problems when watching 3D material. There was also an almost complete lack of crosstalk which meant you never found yourself being drawn out of the 3D experience.
Due to being so light we found wearing the passive glasses to be much more comfortable and far less tiring than with active shutter glasses and often forgot we were wearing them. The horizontal viewing angle is much wider with passive and, because the glasses use circular polarised lenses, they are far more tolerant to tilting your head. However one weakness of passive polarised lenses is that they are less tolerant to vertical movement, move your head up or down by 20% and you will lose the 3D effect. This means that you will need to consider the viewing angle in the vertical plane when installing your display and positioning high on a wall could be problematic. There are of course no batteries to worry about, no turning them on/off and no problems with synching or flicker. It is this simplicity that makes them appealing to children and those of a non-technical nature and they are also robust and cheap to replace. In fact you might well have some already lying around your house because the RealD polarised glasses used in the cinema will work just as well with LG's Cinema 3D displays.
The big stumbling block for passive 3D is the perceived loss of resolution that results from the use of two interlaced images. With 3D Blu-rays you are essentially losing half the horizontal resolution and with Sky which is delivered as a side-by-side format you are losing both horizontal and vertical resolution. However when actually watching 3D content you are never really aware of a loss in resolution. There are a number of reasons for this but by far the most important is that the brain places more importance on depth that it does on resolution. This means that although the resolution is lower the additional depth cues result in an image that appears just as detailed. We actually had an active shutter display in for review at the same time as the 47LW550 and by sending a simultaneous 3D image to both we were able to do direct comparisons. At any sensible viewing distances the differences in resolution just weren't noticeable unless you actually looked for them. Overall we always found the passive 3D image to be preferable due to the increased brightness, the lack of crosstalk and flicker, the wider viewing angles and the lighter more comfortable glasses.
Whilst active shutter remains our preferred method for use with projectors due to the higher resolution we do feel that passive offers a far better experience on TVs. There is no question that passive technology offers the best hope for 3D to reach mass market acceptance because it makes the format both simple and accessible to the whole family - especially for communal experiences such as sporting events and concerts which will require lots of glasses. Whilst the actual resolution might be less than active shutter this is far less important than factors such as brightness, lack of flicker and crosstalk, ease of use and especially cost.
- Excellent out-of-the-box colour reproduction
- Reference colour reproduction after calibration
- Excellent out-of-the-box greyscale
- Reference greyscale after calibration
- 3D images are bright and flicker free
- No discernable crosstalk
- Very cheap 3D glasses
- 3D glasses comfortable to wear and easy to use
- Reasonable off axis performance for an LCD display
- Colour Management System
- 10 point greyscale controls
- Well designed and responsive menu system
- Impressive internet platform
- FreeviewHD built-in
- Mediocre black level and contrast ratio
- Some minor issues with backlight uniformity
- Unable to display full 1080p 3D images
LG LW550 (47LW550T) 47 Inch 3D LCD TV Review
The 47LW550 is an attractive, well designed and solidly built LCD display that uses LED edge lighting and incorporates localised dimming. The out-of-the-box greyscale and colour accuracy are excellent and thanks to a reasonably comprehensive set of calibrations controls, a reference performance can be achieved. The video processing is also excellent and as a result both standard and high definition material looks very impressive in 2D. The addition of Smart TV is a major improvement over last year's internet platform and the connectivity and multimedia capabilities are also excellent.
Whilst LG have been slightly misleading in their promotion of Cinema 3D they really needn't be because the lower resolution of passive technology just isn't an issue. We found that the use of a filter didn't adversely affect 2D performance and the 3D performance itself was excellent. The 3D images were bright and flicker free and combined with the lack of crosstalk resulted in a hugely enjoyable 3D experience. We were never aware of a loss in resolution when viewing actual material and thanks to the light glasses we often forgot we were wearing them. The simplicity of passive 3D technology coupled with the cheap glasses makes the format far more accessible to people who aren't technical, have large families or young children.
The only areas where the 47LW550 didn't perform as well was where LCD displays have an inherent weakness such as black levels and motion handling but this is largely expected. The 47LW550 also uses edge LED backlighting and although there was some brightness at the edges the overall backlight uniformity was better than some other LED displays that we've seen recently. The only area where the 47LW550 really disappointed was in terms of input lag and even in the optimised Game mode the best measurement we could achieve was 90ms. However a recent firmware upgrade appears to have addressed this issue and brought the input lag down to around 25ms in Game mode which would make the 47LW550 and ideal display for 3D gaming.
The LG 47LW550 offers excellent 2D performance coupled with a highly enjoyable 3D experience that will delight the whole family. We would highly recommend the 47LW550 to anyone who is looking for an accomplished 2D display that can also give them their first taste of 3D, especially if they have a large family or young children.
3D Picture Quality
Ease Of Use
Value for Money
Contrast/Dynamic Range/Black Level
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