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inofficiella AVforums bloggPanasonic VT20 (TX-P50VT20) Review
Posted on May 14, 2010 by avforums
Introduction
When Pioneer announced that it was withdrawing from the Plasma TV market many an AV enthusiast felt a heavy heart. The Kuro screen had created a legacy in its short life for absolute reference level images from a consumer TV and many of us thought that it was curtains for quality products. We all feared that quality images would take a back seat to price cutting in the TV market and that AV fans had lost any hope of seeing another reference screen. During those dark days it was reported in the Japanese media that Panasonic had not only hired a large number of Pioneers plasma engineers, but also the patents to the Kuro technology. However at a recent meeting with some of the company’s engineers that part of the story was denied.
The VT20 represents the first Infinite Black Pro TV to be released from Panasonic since the fall of Kuro and when I saw it at CES I was excited by the fact that what we saw was very Kuro like in appearance. Since CES and before the production sample we have for review arrived, I had witnessed the VT20 twice again and each time it looked like subtle changes had been made since that initial CES outing to improve the image further. So with no prospect of buying a Kuro anymore it looks like the VT20 already has a lot of weight on its shoulders to be the reference screen replacement for many AV fans, but, will it live up to its own hype?
Design
When we first received the PR about Panasonic’s 2010 range it was surprising to see that their flagship VT20 was to be brown in colour. Well at least that’s how it looked in the PR pictures. But when you actually meet the screen in the flesh its not quite as bad as the PR might have made it out to be. There is a slight bronze tinge to the bezel rather than the usual gloss black and I for one think it looks very stylish indeed. Obviously design is a very personal thing and I wouldn’t want to talk for everyone here, but to be honest the screams of derision from some forum members were perhaps a little over the top and premature. The stylish bronze finish is highlighted by the one thing I do dislike; the silver strips. Again this will be a personal thing but I would have much preferred the finish to have remained sleek without the silver bling being added at what looks like an after thought. Love them or loath them, Panasonic have certainly never felt the need to take a designer approach to their TV chassis and to be honest that has never bothered me. However, in today’s fast moving flat panel market there will be some consumers who will think that the boxy looks of the VT20 are outdated when compared to its Korean rivals.
The stand provided in the box for the VT20 is again a nice touch if a little odd looking in size. Sitting next to our reference Pioneer LX5090 the VT20 stand looks like it is too small for the bulk of a 50inch screen and that it might topple over during a bout of Wii fit (sorry for the mental image now placed in your heads for those who know me!). However, the stand is thankfully heavy and strong enough to take the screen quite conformably; and it is sturdy when table mounted. Those who wish to wall mount the screen will find that there are standard mounting points on the rear plate of the chassis.
The remote control provided with the VT20 sadly doesn’t have any designer flare and is your now typical Panasonic design made from plastic. It is well laid out and thankfully there is no sign of the annoying ‘N’ button. This used to be close to commonly used control buttons and when pressed would wipe your picture settings stored in the TV. Overall it is intuitive to use and provides all the common buttons close together.
As the VT20 is also a 3D TV it comes with two pairs of active glasses in the box. These are stored in well constructed plastic boxes with two nose fixings and a lanyard so you can have them hanging from your neck. The design is quite unique when compared with competing models from other manufacturers with the lens portion seeming to float in front of the main body of the glasses. While this looks stylish it also causes some issues during use. Because the sides of the glasses are not covered or blocked into the frame, it can allow light from behind and to the side of the user to reflect on the inside of the glasses. In the worst case scenario this can cause the glasses to appear dirty due to the reflection and spoil the 3D effect. I would suggest that Panasonic maybe needs to think about this design flaw for its next range of specs.
As someone who doesn’t normally wear glasses in everyday life, I found the active glasses a little heavy and uncomfortable around the nose. There are two attachments provided in the box that simply push into the provided grooves, but I found that these just cause more issues for me personally. I decided to use the glasses without any nose clips attached as they felt more comfortable over a period of time wearing them. I guess its certainly going to be a very personal thing when it comes to wearing the 3D specs with the VT20, but hopefully as the technology advances we may start to see designer brands and lighter active glasses becoming available.
The final item included in the box is a WiFi dongle which allows connection to your network and the internet without having to run an Ethernet cable to the back of the TV. This is a simple design that will be hidden from view when used in one of the USB ports on the side of the TV.
Connections
As the VT20 is Panasonic’s flagship PDP for 2010 (although we understand the Z1 will continue to be available) it only seems right that it is packed with every connection possible on the rear and side panels. We get four HDMI V1.4 slots with three positioned on the rear of the panel and one on the side. HDMI 2 is the connection on the VT20 which allows the new Audio return signal as part of the 1.4 spec. This means that you can feed the TV direct from a blu-ray player and then feed the audio back from the set to your AV Receiver. Also on the back panel are two RGB scarts, one set of component RCA plugs and a VGA PC slot. There are also audio inputs and outputs using RCA plugs and an optical audio input. For the Freesat HD feed is a satellite socket, and Ethernet connection and a standard RF socket that will accept Freeview HD if you have the right aerial and you are in an area where it is broadcast. One strange omission is an RS232 control port or any kind of control interface with the VT20. We can’t help but think that Panasonic has missed a trick here with custom installers. Or if we put our cynical head on for a second; it’s a way to differentiate the VT20 from the upcoming Pro series?
Moving to the side panel and we are greeted with two USB inputs, a common interface card slot, a composite video input and further audio inputs along with an SD card slot and 3.5mm headphone jack. Rounding off the side panel is the main power switch and basic volume and channel buttons.
Whilst we welcome such comprehensive connections we do have an issue with the way the slots are positioned when it comes to wall mounting the TV. Although the rear panel is recessed slightly we cannot help but think that at least the HDMI and Power Socket are positioned at a right angle and recessed to allow better wall mounting options. Just a small niggle, but a niggle none the less.
Menus and set up
Moving on to set up of the VT20 and as soon as power is fed and the TV switched on it automatically takes you through digital (and analogue) TV set up. We tried this 3 times and it worked perfectly every time storing the available channels. This was also true with the Freesat HD tuner once connected to a satellite feed. Next was to select ‘Home’ mode and then you have the option to enter your personal details and postcode into the TV to help if your set is ever stolen.
Next we move to the main picture menus to select our best settings. The Panasonic menu design hasn’t changed in a long time, so those used to using them should find their way around the available options with ease. Obviously with the 2010 range we finally have all the controls we could possibly need to get the best out of the VT20. Well almost all. Some options available within the menu system will change depending on what picture modes are selected. However, as you should set up your TV with images that follow the standards for day time and night time playback, I don’t see that as an issue.
Looking at the main picture menu your first choice is to pick a picture ‘Viewing Mode’. Your choices in 2D mode are Dynamic (yuk!), Normal, Cinema, THX, Game, Photo and Professional 1 & 2. The new options (Pro 1 & 2) are those requested by AVForums members and the review team last year which contain ISFccc picture set up controls. These give access through the Advanced menu to controls for Greyscale, Colour Gamut points and Gamma. Although nearly all the controls we requested at a presentation to Panasonic are included; the lack of a full 3D Colour Management System (CMS) is in our opinion a major omission given almost all their competitors have one. We will see how the controls work when we come to calibrate the VT20 later in the review.
Other options worth looking at are the C.A.T.S system which attempts to adjust the contrast performance depending on what the lighting and environment conditions are. These types of auto systems are never accurate and can cause the image to fluctuate by some margin so we left it switched off. Also here on the first menu are options for noise reduction settings, picture in picture, picture display on or off, the advanced menu access, plus options to lock settings and reset to default. These are you options in THX and Professional modes. However, if you switch to Game, Cinema, Photo and Normal you also get further picture controls for Colour Temperature, Vivid Colour (called 3D CMS last year) and Advanced White Balance including Gamma. In 3D mode the picture presets change to introduce ‘True Cinema’ in place of THX as there are no THX specifications or certification yet for 3D picture settings.
For sound options there is a full menu allowing two selections for music or speech and one that introduces a custom set up. This includes an EQ system so you can change the audio to suit your room if you don’t use a stand alone audio system. I would suggest however that such a TV will warrant the use of a full 5.1 stand alone audio system to get the best out of the VT20’s movie and 3D playback options. In terms of audio quality the Panasonic does its best with the speakers built-in and will do perfectly ok in a normal living room. Just don’t expect the type of dynamics and bass weight that a separates system will give you. Bass is fairly light but the main stereo speakers do an acceptable job.
Finally we look at the 3D set up menus and what options you have. If you use a 3D Blu-ray player, such as the Panasonic BDT300 we had with this review sample, and use HDMI 1.4 cables the TV will switch automatically to 3D mode. This defaults in the ‘Normal’ picture mode and this is important as light output is critical to get the 3D effect to work correctly. There are no picture standards yet in place for 3D content and because the technology uses active glasses that have dark lenses, it is important to get enough light through the glasses to combat colour balance issues. This is why the VT20 defaults in auto mode to the ‘Normal’ preset that has the effect of providing enough light output and addressing colour balance issues. If you are using the Sky+HD box or Sony PS3 you will have to switch the VT20 to the correct playback system option. These are Auto, Side by Side and Top and Bottom. The one big plus point was that when I used a standard HDMI 1.3 cable (QED) with the Panasonic BD player and the VT20 it also automatically switched the TV to 3D mode and was quite happy playing back full HD sequential material. Other settings are Picture Sequence which reverses the left and right eyes, and Edge Smoother which applies some smoothing to the image. I found this setting robbed the 3D image of fine details and left it off.
Extra Features
As well as the two HD tuners included with the VT20 we also have Panasonic’s Viera Cast online content service. This is restricted to the content provided on the service and does not allow full internet browsing. Apart from You Tube and Picasa I couldn’t find anything else of any interest here. Indeed after playing around with You Tube for half an hour I never felt the need to access this section again. Also included with the TV in the box is a WiFi dongle to allow connection to your network (or you can use the Ethernet slot on the rear of the TV. The VT20 didn’t take long to find the network and after entering the access key I was able to browse the 8 hard drives I have running in my system.
Intelligent Frame Creation and 600Hz
I normally talk about the picture processing of the TVs as a dedicated part of a review, however because there is so much marketing about these two features it is probably wise to have a separate area dedicated to them.
So first of all we have the Intelligent Frame Creation (IFC) which is a motion compensation technology that interpolates frames. Basically this means that the TV look at upcoming frames in the TV show or Film and then guesses what frames should be added in between to make motion look smoother. The positive effect of this is that all 1080 lines of resolution should become visible on screen. However Plasma technology because of its fast response times doesn’t really have an issue with motion blur like an LCD TV would. Without the IFC function switched on and using the FPD Benchmark Blu-ray test pattern we could clearly make out just over 900 lines of resolution on the moving chart, with IFC turned on it made the resolution more stable. However it also added some artefacts to the image. When moving to real world material on both TV tuner and Blu-ray with IFC engaged (it’s called 24p smooth film when BDs are played) the image did look smooth but also gave the image a false ‘soap opera’ look. This means that film which should have a certain look to it, now looked like it was shot on cheap digital video cameras. This completely robbed the image of what natural motion it should have and I would recommend leaving it switched off. Not only does motion look odd with IFC on both Film and TV shows but the processing also adds in artefacts where its guessing goes wrong.
So then we have 600Hz and how the technology is sold to the public as being a motion technology like other manufacturers 200Hz systems. This is not the case as you have two issues at play here with the Panasonic system. First of all 600Hz (also seen on Samsung and LG plasma TVs) is not the same as 100/200Hz systems. It refers to how the subpixels that make up the plasma image work. It all comes down to the frame rate and how many subfields are used to make up one frame. These subpixels do not directly affect motion but rather make up the image being drawn on screen within each frame. Where Panasonic confuse matters is when this natural way of making images in a plasma panel is introduced to the IFC system and gets called IFC sub field driving. So with my cynical hat on again for a moment this 600Hz technology is a marketing department invention to compete with the 200Hz LCD sets, and yet it’s nothing of the kind in practice. So do you need to worry about whether to buy a 600Hz screen or a 200Hz screen? No you don’t as they are completely different beast’s altogether. Plasma technology doesn’t really have issues with motion blur like LCD so the figures in real life use are a non-issue. It’s another big number for marketing departments to use.
Out of the box measurements
In this section of each review we fully test the TVs picture modes by measuring the greyscale and colour performance referenced against industry standards laid down for TV and film playback. Why is this important? Well TV and film images are made to standards that say what colours should look like and what colour white should be. By matching these standards with the TV we can then see films and TV programs as they are intended to be seen with the correct colours and white levels.
The reason why not every mode in the TV has the correct image components is more to do with selling you a TV than image quality. Plus bright and garish images scientifically attract the eye and give a false impression of picture quality. This is like turning the sharpness control to full thinking that you will see more detail, when in fact you are covering up all the fine detail by doing so. Just the same is true of picture modes like Normal and Dynamic where the brightness and oversaturated colours mask fine detail and nuances of colour changes and skin tones. The most important part of the image is the Greyscale which is every shade of grey from full white to full black. This is made up of the RGB system with the three colours mixed in the correct amounts to make up the shades of grey that make the backbone of the image. If the mix is wrong at any stage from black to white you will see colour casts in the image and at the low end problems like blue, green or red coloured blacks. On top of a correct Greyscale is the colour gamut which states where the primary and secondary colours should be. This refers to their saturation, hue and brightness. Like the greyscale the primary colours are mixed in various amounts to make up the secondary colours and everything in-between. So in simple terms the Greyscale should be as accurate as possible from black to white with no big errors and then the gamut on top should produce natural (and accurate to the standards) colours. That’s not everything as issues like Gamma then come into play but all are measured to give you the full details on image quality.
So the interesting point with the VT20 is that Panasonic have taken on board the industry standards and have introduced some picture modes that try to mirror those standards and also provide further controls to calibrate the image perfectly to the desired points.
On the VT20 we have the Cinema mode, THX and the professional 1 & 2 modes. When looking at the most accurate settings out of the box to our desired reference point then the THX mode should provide that. The THX picture preset has the Greyscale and Colour points set in the factory to try and match the standards for Pal and HD playback. The user then has control over the brightness and contrast to fine tune (with the use of test patterns) to their viewing room. This is the best approach available other than a full professional calibration. But all this does come with a word of warning. THX mode is designed to try and be a catch all setting and as such will never be 100% accurate, ever. It is however more accurate than other selectable picture presets. So lets see how it measures up against our reference points.
All our testing was done after the VT20 had completed 100 hours of continuous use. We would have liked to have added even more hours to the panel but review deadlines and the fact we only have it for a week, meant that we had to live with four and a bit days of constant use.
We start with the Greyscale measurements. THX is designed to be a catch all setting that attempts to be as accurate as possible. During certification the Panel must hit certain points and be able to do so in the field. As these points are a trade secret, sadly we cannot publish them. Looking at the tracking and balance charts for RGB we can see that blue is compared to where it should be for reference results. Red and green are high at approximately 5% over the 100 percent mark. Luminance of the Greyscale is alos a little high here and Gamma does attempt to track our reference 2.2 point but is a little skewed at around 70ire up.
So what does that mean in terms of what you see on screen? As the errors (Delta E) are just a smidge over 4 they can be described as fair and with a high green and red in the mix, onscreen images are not quite perfect. With a lack of blue energy the image has a slightly yellow tinge to proceedings with skin tones in most material lacking that rosy fill of the cheek bones. Instead flesh (and the rest of the image for that matter) looks a little yellow and green in places which points back to our results here. Had blue been higher we would have seen a better and more natural blend of tones over the whole image. This is not a deal breaker as things are not a million miles away, but they could have been better than what we see here. This certainly highlights the fact that even THX mode cannot beat a proper professional calibration, but it does give users a good starting point towards accuracy.
Moving next to the colour points and here we have a far better result that almost hits the standards perfectly. The CIE chart above shows that the primary and secondary colours are within the region of Rec709 with very few errors. The errors that are seen are with Blue saturation being low and our secondary colours showing slight hue issues. You will also note our white balance greyscale results in the black curve; as white is just short of D65. Luminance of the colour points are also important and we can see here that those are under control. Most users will not see the slight errors on screen and only those with a reference monitor sitting next to the VT20 would likely see them.
After looking at the THX mode and its results we also have the two professional modes. These are based in their out of the box measurements on the same points as the THX results. However they offer the flexibility out of the box to be set as a night and day setting. This means that you can change the brightness for daytime viewing and then use the other for night or dimmed environment viewing. It has to be pointed out however that one properly calibrated setting to the standards at the right luminance levels should be fine for all material and viewing (unless you have an over bright day time viewing room). The advantages here are that you have the choice to either get the very best out of the box settings, get even better with a professional calibration or choose your own if needs must (just remember you wont be seeing everything as intended). So lets move on to a full ISF calibration.
Calibrated Settings
Panasonic have to take a great deal of credit for adding in the calibration controls we all asked for last year, but not everything is a bed of roses. The first thing is the Colour Management System (CMS) that has been included this year. This is not what was asked for and the reason why it is so restricted can only be answered by Panasonic. As it happens the colour gamut performance in the professional mode is fairly accurate, however total control over both primary and secondary points in Saturation, hue and luminance (brightness) would mean that full calibration results could be obtained. Plus while the addition of full white balance controls for greyscale is welcomed, why skimp there? LG has offered a full 20 point control for a number of years now. So while the introduction of calibration control is welcomed, there is still some way to go for Panasonic.
But the biggest issue we have with the new calibration tools is the menu system. You have to ask what the point of adding all these controls is when you cannot use the white balance or CMS adjustments because the menu sits over the meter measuring point. Even when you adjust a setting and the main large menu disappears for a millisecond to give you the slider control, you have no time to adjust and measure before the main menu reappears and covers the meter! And then when you reach half way down the menu page for say the white balance, the actual slider is now covering the meter! It is pretty clear that this hadn’t been tested before release of the menu software as it is a pretty obvious issue. Now some might suggest using full raster’s and moving the meter point, but as this is plasma that really is a no go. Sorry to sound so down on Panasonic here, but it really does defeat the point and calibration takes an age. All we need is a system where the slider adjustment is selected and it stays on screen more than a few milliseconds. If the adjustment slider is selected it should be at the bottom of the screen well away from a window pattern and remain there, even if there is no input from the user, until deselected.
Update: After a long telephone conversation with Panasonic the issues with the menu system has been reported. If we get any further feedback or even word of an update to solve the issue we will update the review accordingly.
Ok, so with our feedback and frustrations out of the way lets start the sadly quite laborious task of calibrating the VT20 for 2D images.
Taking Greyscale results first we can see that after some hard work we were able to get the tracking and balance of RGB points to reference levels (note the scale of the chart). With errors (Delta E) just a smidge over 1 at the low end we can mark this result in the reference box. Our only slight issues are that we would have liked to have corrected the luminance just a tad more and obviously get the high end of the gamma track bang on 2.2 but as it is these slight issues should not affect overall picture quality in any detrimental way. However, I would like to see 20 point correction and full gamma tools added for next years models so we can fine tune them to a millimeter of perfection. A display of this level deserves that.
Next we move back to our CIE chart to check our colour points. Overall with that greyscale calibration helping to seat the secondary colour points where they should be and a slight nudge on the blue saturation; we again hit the reference score box with the results. This is a hugely satisfying moment for anyone who has struggled trying to get Panasonic panels to look accurate over the years. Obviously a full 3D CMS would have been nice (and I still want one for next year Panasonic!), but in the end we managed to coax excellent results. Those observant amongst you will notice a slight rise in Luminance results, however that is all down to getting blue back to where it should be, so we are happy with that slight rise and its still within our desired error points.
Now the issue of 3D picture calibration is an interesting point to make here. As there are no standards yet set down in stone for brightness, colour balance and so on we didn’t calibrate the VT20 for the 3D mode. The reason for that is quite simple. You have to take the material at the screen and then work out what affect on the main picture elements the glasses have as they are a second filter and darker. The VT20 defaults to Normal in 3D and we would suggest that for colour balance issues and brightness, this will do until some standards are laid down.
Picture Processing
Moving on and one area where the 2010 Panasonic have improved is with the Picture processing side of the equation. In the past the scaling and de-interlacing performance has not been that great from the brand so it is interesting to see how things have improved…in some areas anyway.
Feeding a Panasonic Panel in the past resulted in soft looking scaled images from 480i and 576i material. Thankfully that has changed significantly with the VT20 which scaled images resolving excellent detail and doing so without adding in any ringing to fine edges or blur. The HQV jaggies test in SD passed with just some very slight jaggedness on the bottom bar in the test material. This points to good quality diagonal interpolation which suppresses such jaggies in SD content. This was also evident watching actual content on the VT20 such as Fulham’s tragic near miss in the Europa Final. The lines of the football pitch, (often a source of jaggies) where crisp and solid with no signs of issues. Obviously the tragic broadcast quality of FIVE also helped cover up issues here. So far so good.
However, when it comes to film based cadence detection we hit a snag with the VT20 as it again provides none. This has been fed back quite a few times to Panasonic now and hopefully (as seen on our recent video podcast interviews) will be fixed soon. Obviously if you have SD sources that handle the upscaling, like a Cable or satellite box, or a Blu-ray player, you can get around this issue easily providing there film detection modes work. However the issue does affect the VT20’s SD tuners and sadly there is not a lot you can do here.
Moving to HD material provided excellent results with both interlaced and progressive formats. We saw no issues to detract from your viewing pleasure and also no back door processing interfering with the HD images. 24p playback was again in multiples’ of the frame rate with no interpolation unless you use the 24P smooth option. However, with film material this adds unwanted artefacts and motion looks strange. We would advise this option is left off.
Flicker, Image Retention and Black Levels rising
Three of the most hotly discussed issues on the forums with regards to Panasonic Plasmas and at least two of them are here in a small degree with the VT20. The third is still an unknown.
I very rarely see flicker on PDPs and it is an issue that is quite personal to each and every viewer. Some people will see it on all or some PDP panels, yet other people don’t see it at all. It all depends on how the PDP processes and displays its image and how sensitive you are to seeing the effects of this. In normal cases it will depend on individuals and we would recommend that you always demo a display before purchase. The VT20 to all intents and purposes is the same as any other PDP panel, however on some occasions I have seen the image flicker, normally with contrast heavy material. This was very obvious on first setting up the TV but as it has racked up the hours this has happened less and less for me. There is no doubting that with fast phosphor technology and a reverse in subpixel processing has been introduced with the VT20 and it could be this approach that is perhaps making the appearance of flicker more pronounced for people. Like we say it is a very individual effect that will be different for each person. The VT20 does not flicker in an obvious manner for me here and in terms of this review we don’t see it as a major issue to take out of proportion, just be aware that it is there for some viewers and demo the set before purchase.
Next we move on to Image Retention. This is an effect that is seen on every plasma TV to varying degrees and will either be noticed or not. This is not the same as panel burn-in and we would be surprised if anyone these days could permanently damage a Plasma screen with normal or even heavy use. It would in our opinion require some abuse to burn-in a panel these days. Image retention is different as it is not permanent and usually disappears in time. How long it takes to disappear is usually down the make and model as some manufacturers screens seem to be more susceptible than others. On the VT20 you have to look very hard to see any retention and we had to put up a 100ire raster to show the effect in the image attached. In that case the logo had disappeared within a few hours of continued use, with me checking every hour by re-showing the raster test pattern. In normal viewing, even straight after seeing it with the test pattern I couldn’t see any retention with programme material running on the TV from any distance. So while retention is there on the VT20 you have to go looking for it and it is unlikely to cause any issues for normal viewers. In fact I ran a second test before sitting down to write this section of the review with the panel now having about 105 hours on the clock and the effect was less obvious in this second test. It is certainly not an issue on the VT20 when compared to the latest plasma panels from other manufacturers covered by AVForums reviews.
Finally we come to what has turned into a hot potato for AVForums members and that is the reports of black level rising on 2009 Panasonic models. Sadly Panasonic has remained very quiet about this issue in the UK and have given us no guidance either on or off the record as to whether it is a design in the panels or a fault caused by the way the panel is designed to work. Basically all we have to go on is the reports on AVForums and other sites around the world from actual users and, of course, the only statement in existence from Panasonic in the USA. First of all we look at the statement from Panasonic in the US and apply that to the 2010 models as we have nothing else to go on. It states that there is a programmed voltage rise designed into each Plasma TV that helps the panel continue to produce its excellent pictures as it ages. The statement also states that this design is in the 2010 sets and that it is designed to work in a more gradual and refined manner compared to the 2009 sets. So if we take that statement as being accurate, and at this moment in time there is no other official line from the company, then the panels such as the VT20 will have this voltage rise built-in and it should be gradual and more refined than last years models.
Plus, being objective about this issue in terms of this review, we cannot test or measure the effect this may have until we get a Reference set for a long period of time in our review room. However, the measured results we do have after 100 hours are inconclusive and as we have no further details provided by Panasonic, all we can do at this stage is report on the performance of the VT20 as it stands now and hopefully update this review as and when we can.
So the stance has to be at this moment in time that the statement holds true until its withdrawn and replaced with more details and we have to take that at face value, and not blow this issue out of proportion for 2010 models. Plus our results so far with the VT20 point to it being an excellent TV which has provided some excellent measured results. So we can only objectively assess what we have here for review, and update as time passes where we can. We will take the same approach with all Panasonic Plasmas going forward as they are marketed as having infinite black levels and we expect them to still have infinite black levels throughout the panels life. The evidence of whether there is an issue or not is inconclusive but there are concerns that have been raised and we mention them here in respect for our readers. Readers can follow the owners thread for the VT20 here.
Picture Quality – 2D TV
So, lets answer the first question posed in this review and of course, the one thing everyone wants to know about, is the VT20 a worthy successor to the Kuro?
The answer is not a straight forward yes or no and for good reason. First of all we have the black levels and they are the best looking blacks Panasonic has ever introduced on a Plasma screen. They are close to the Pioneer standards and if they stay the same depth during the life of the TV, offer an interesting look at the future route of plasma. But does the VT20’s black levels match or better those of our two year old Reference LX5090? No they don’t, but they are not far off to be honest. Indeed its only when sitting both panels side by side and in dimmed lighting that you can see that the Pioneer still has the edge on the VT20. What is also striking with the VT20 when sat next to the Kuro is the effect the new screen filter has at rejecting ambient light. Even in well lit rooms the VT20 doesn’t follow the usual plasma trait of washing out its black levels and image detail. The filter manages to work just as well as the original Pioneer filters and allows the VT20 to be used in rooms other plasmas would struggle in. The filter doesn’t stop reflections on the screen and this is still one area where it may struggle in a bright room, but looking too at the new breed of LCDs; they all now have the same reflective glass panel surface so its probably not that big a disadvantage in real terms for the VT20.
We mentioned earlier that the VT20 also has a newly designed faster phosphor discharge design, which was introduced for the fast moving 3D side of things. However, this also has an advantage when viewing in 2D and that’s combating the phosphor trailing (or purple snakes) that used to be a common problem on previous Panasonic models. This phenomenon is now almost non-existent in the VT20 even when playing PS3 games with fast moving content.
Looking at our measurement graphs for the THX mode I mentioned that images can look a little on the yellow side in this preset, and that is true when I sat down to watch Public Enemies on Blu-ray. Colours look accurate and there is a good sense of depth where required thanks to that excellent black level. Shadow detailing is also good in out of the box settings with fine details in the higher end of the image also present. Skin tones can however look slightly yellow because of the greyscale characteristics in the THX mode and a little more accuracy would have been good. Even images from the Freeview HD tuner looked clean and there was a nice sense of sharpness on the better bandwidth channels.
Moving to the calibrated settings improved matters further with a better gamma curve adding a greater sense of dynamic range to proceedings. Here AVATAR was able to show its true depth of field in 2D form; and was a good advert for staying with the traditional style of film watching. Colours were again excellent and the corrected grayscale helped produce accurate skin tones with the right amount of reddish hue to cheek bones, adding some life back to proceedings. Obviously that only applied to the human characters!
But it is the improved black levels of the VT20 that really make this a stand out TV. While the final depth of the Kuro is not quite here, there are also some things the Panasonic does better. One is the sharpness of image available thanks to the images clean look. There is a reduced amount of PWM noise like the image we experienced with the 50inch VX100 early last year. This makes the image look crisper although it is not producing anymore detail than the Pioneer. Shadow detailing is also more pronounced on the VT20 due to its dynamic range, that is sure to entice viewers to search out those darker titles. However, there are also some small niggles caused by this cleaner image and in particular colour gradation with certain material. Scenes such as a sunset, where the sky has light to deep blues, in gradual gradational steps, there is banding within the VT20 image. This is not a common issue but once you are aware of it; you can be taken out of a particular scene you are watching. Whether this is caused by the lack of dithering used by Panasonic is open to debate, however there were also instances where posterisation was seen within backgrounds and occasionally on faces. However, these issues while annoying to videophiles are probably not going to be that obvious a flaw to the vast majority of viewers.
Overall in 2D picture mode the Panasonic VT20 offers up the best flatpanel TV pictures we have seen this year, and as the Pioneer Kuros are now rarer than rocking horse droppings to buy, it offers the best performance levels on the market as it stands at this time.
So, with ringing endorsements’ for its 2D performance, how does it handle 3D? Don’t tell me that after reading all that you forgot it was a 3D TV?
3D Picture Quality
Whilst the VT20 is the first review sample we have received that also does 3D playback, we have experienced all the different TVs heading our way this year and their versions of the technology. It won’t be a fair contest in image scrutiny until we have them all up against each other, but we do believe that we have a good enough handle on what to expect to say that the VT20 is probably the best of the bunch.
The reason for this is the new faster phosphors and the lack of an image artefact called crosstalk. This artefact is caused when one of the images show to one particular eye stays on screen or in the glasses just long enough to interfere with the next image. Our 3D Guide video explains this in more detail for those interested in finding out more. On the LCD TVs we have witnessed so far this year this issue has been present in almost all the content viewed and can cause the image to appear blurred. This is down to the response time of the panels and the sync with the glasses on active systems. However, on the Panasonic this is just not an issue at all and the 3D experience is far better for it.
Putting aside the arguments for and against 3D for a second, the actual performance of the VT20 is pretty special. Images appear sharp and well defined with a good sense of colour balance and detail. That is despite the glasses adding in light loss to proceedings. We stayed with the Normal and Dynamic modes for 3D so enough brightness was getting through from the screen without affecting colour balance too much. This is a drawback of 3D viewing and of course while there are no standards, it is a bit of try it and see.
But watching actual content from Sky, Blu-ray and some gaming from the PS3 my 3D skeptic sensibilities were starting to wane after a few days of sampling the technology. It will likely be a different experience for people who are susceptible to flicker issues as the way the glasses and the sequential frames are processed is probably going to be visible to a few. That will be a shame as the experience can be quite enjoyable and gaming is certainly immersive.
I don’t think it will be films that sell 3D technology to the mass market, but rather sporting events and gaming. I am not a gamer at all, but was inquisitive enough to go out and buy the AVATAR game for the PS3 and give it a go. It turned out to be quite an experience and I soon got lost in the depth of the image and gaming experience. This is where this technology is going to be massive! The Sky material is quite limited at the moment but I found the football and Rugby preview clips to be an enjoyable experience that made me want to see more. And the same is true for documentary footage of wildlife and insects where the effects are not of things jumping out at you, but the depth of field on offer. Sadly the only Full 3D HD material I had to hand was Panasonic’s own demo BD which is a mix of different short features and trailers. Some of these did look a little on the gimmicky side and not all of them were full HD, which was a shame with the female beach volley ball sequence.
There were only a few little niggles with the 3D side of things during my stay with the VT20. The first was the glasses as they were heavy and not very comfortable. Plus the sync from the TV to the glasses is prone to break up if like me you have another plasma sitting right next to the VT20. The light interference did break the sync a few times as did having the ‘big light on’ as Peter Kay would say. But other than that I was pleasantly surprised that my 3D sceptic side definitely started to defrost a little after living with it (although content is still restricted). And on all the evidence we have at the moment the VT20 does the whole 3D thing better than anything else we have seen so far, so its our first 3D reference point.
Gaming performance
As I have already mentioned my new found love for gaming in 3D, in normal 2D gaming the VT20 has an almost non-existent Lag time of 10ms in Games mode and every other picture preset. I doubt even the fastest gamers out there would notice any issues with the speed of the VT20 at responding.
Power Consumption
I tested the VT20 over 10 minutes of regular channel 4 viewing looking at the peaks and dips in consumption. Because plasma is a self illuminating technology the power consumption varies with the content shown on screen. High contrast white background material uses more power to create the image over a dark scene that uses less. The highest measured figure was 303 watts and the lowest was 59 watts with normal content. We then move to static consumption figures at 0, 50 and 100ire rasters. In calibrated mode the VT20 measures 60 watts, 210 watts and 390 watts.
Conclusion
In a market of ever reducing pricing and quality, it is refreshing as a reviewer when you get a product through that pushes strongly in the quality image stakes. And that’s what we have here with the VT20 and why I am happy to write reams of text about my experience with this TV. Whilst it falls just short of being a replacement for the Kuro, it is the only TV you can buy now that offers the strengths of our old Reference TV, with its own improvements. There are some issues that do raise their head and which have been covered in great detail in this review. But even with a few minor niggles here and there and I suppose a tiny hint of the unknown black issue, the VT20 is a fantastic achievement for Panasonic and in this reviewers opinion is the best offering in the current TV market for 2D images, with reference 3D images as a bonus.
If you own a Kuro, then unless you want 3D capabilities and give up a little on the black levels, you will probably be wise to wait a while to see where this new line of Panasonic screens go. However, if you don’t yet have a quality screen and are looking for (what we think) is the best out there today, my advice is to go and see one for yourself as it comes highly recommended but the long term black level performance remains unanswered at this stage.
Pros
* Best black levels of any new TV on the market
* Good out of the box performance
* Reference Greyscale and colour reproduction when calibrated
* Lack of PWM noise and clean looking images
* Freeview HD and Freesat HD built-in
* Reference level 3D performance
* No nonsense design and excellent build quality
* Excellent lag times for gamers
* Full ISFccc Calibration controls
* THX Certified
* Two Pairs of 3D Glasses in the box
* Excellent performance with Sky 3D
* Excellent scaling
* Good quality Remote control
Cons
* Uncertainty over long term black level performance
* Some visible banding with certain material
* Calibration menu design gets in the way
* Some light image retention visible
* Some users may see flicker from the image
* 3D Glasses not that comfortable
* Still lacks film cadence detection
* Lack of content on Viera Cast
* Even for an Eco TV it still uses quite a bit more power than LCD rivals
* Extra 3D glasses are expensive
Scores
Contrast ratio/dynamic range
Black level
Colour reproduction out of the box
Colour reproduction calibrated
Greyscale out of box
Greyscale calibrated
ISF or calibration controls available
Video processing SD/HD
3D performance side by side
3D performance sequential
3D performance crosstalk
3D glasses comfort/performance
Sound quality built in
Networking
Features
Ease of use/menus/remote/settings
Value for money
Overall
Our feedback for Panasonic
* We need an official comment regarding the way the 2010 plasma range implements the voltage drive increase as stated by your US statement. That implies that the black level rise due to voltage increase should not be noticeable as the panel ages, unlike the 2009 sets reported on AVForums, AVSForums and Cnet US. A confirmation of this point would help users doubting that the 2010 range will be any different in that regard and that they might see the same issues appearing as last years models.
* Well done with introducing the calibration controls that AVForums asked for. However, as stated in the review the menu system gets in the way of calibration and the CMS provided is not adequate. Please sort the menu issues as a priority as it defeats the point of having them, and please look at a 3D CMS, 20 point Greyscale and Gamma tools for next years range.
* Flicker is still an issue for many users with NeoPDP panels. Although the VT20 does improve with run in, there are many who will still be able to see it even after the set is well run in. Any engineering fix that reduces this issue is bound to help.
* Banding is still an issue with the NeoPDP panel and whilst rare to notice with the vast majority of material, this could be improved.
* The 3D Glasses, whilst adequate for comfort, need to be lighter and easier to wear. The reflections from the open lens approach with light coming into the units, from the sides and rear of the person wearing them, needs to be addressed as not everyone will watch in dark surroundings.
Redigerat av larssoningrid, 14 May 2010 - 11:52.
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