Black Level
Having added a new Klein Instruments K10-A meter – which has even better dark measurement capability than the original K10 – to our arsenal of equipments, what better panel to check it out with than a 2013 Panasonic plasma?
In our calibrated “Mid” [Panel Luminance Setting] mode, which is the mode that arguably provides the best balance of picture brightness and noise-free picture quality, blacks measured at an incredibly dark 0.0033 cd/m2, which is actually the same reading we got from the 55-inch version of the VT65, and also from the TXP60ZT65B. Therefore, it seems that the superior black level of the biggest panels has filtered down to the smaller sizes, too. A peak white window returned a measurement of 115 cd/m2, which is impressively bright for a 65in plasma TV (although not at the same brightness level as Samsung’s F8500 plasma, which is revolutionary in that regard).
With the “Low” panel light output mode, blacks raised to 0.0063 cd/m2, which is a little higher but is still outstanding. In this case, a white window measured just 74.40 cd/m2, which may be enough for users in a dark environment, but would appear somewhat dim in others.
Safe in the knowledge that the “Mid” panel luminance setting is in the sweet spot for contrast performance and picture quality, we moved onto ANSI measurements, which place black and white patches on screen simultaneously in a checkerboard layout. We measured blacks of 0.0039 cd/m2, and whites of 66.74 cd/m2. The lower white level measurement here is caused by the plasma’s automatic brightness limiting. (Many LED LCD televisions are now implementing dynamic backlighting which actually causes a similar effect in this test, presumably because they see the amount of black on screen and dim their LEDs). The fact that the Panasonic TX-P65VT65B can hang onto its extraordinary black level depth while half of the screen is lit up isn’t a new characteristic, but it is still a real cause for celebration, because the result with real world content is better perceived depth without any annoying brightening or darkening artefacts, or without blacks appearing grey during nighttime scenes (we’re looking at you on both counts, LCD).
Readers have asked us to clarify observations made by Panasonic VT65/VT60 users that the “Low” and “Mid” modes feature different gradation performance. (We’re ignoring “High” because it sacrifices picture quality too much, in exchange for producing perceptually brighter video). These observations are correct; just-above-black details are indeed reproduced with less dither in the “Low” Setting. However, above 5% black, the differences all but disappear, and we still feel that the “Mid” setting is the performance sweet-spot. If you watch a lot of dark content and want absolute rock-solid black details at the expense of brightness, then you can calibrate a “Night” mode and assign the “Low” panel luminance setting to this. We would rather have the higher contrast performance of our favourite “Mid” instead, though.
Motion Resolution
We need some new tests for this, don’t we? Plasma displays have no real difficulty cleanly resolving 1080 out of 1080 possible lines on the FPD Benchmark Software disc’s scrolling chart any more. In fact, on a plasma, this appears to be quite easy. What’s more difficult is to keep naturally smooth tonal qualities during fast moving areas, and indeed, like (nearly) all plasmas we’ve tested, smooth gradients can break into contours during very stressful motion. We still feel that that’s better than these areas smearing into a blur like they would do, or appear to do (due to the way the eye perceives them) on an LCD. To summarise, with very fast motion, LCDs blur, whereas plasmas begin to look a little “rough”.
Standard Definition
When you find yourself looking at SD news channels and admiring at least some aspects of the picture quality, you know you’re looking at accurate video! Such is the case with the Panasonic TXP65VT65B. It has fairly robust film mode detection for movies on TV, and crisp scaling which is better than most standard-def content is capable of. It doesn’t conceal compression artefacts as well as Samsung’s SD-to-HD scaling process, however.
All of the superior colour science attributes apply equally well to standard-definition video – resolution isn’t everything, of course.
High Definition
There’s very little for us to add when it comes to assessing the high-def picture quality put out by the Panasonic TX-P65VT65: it’s simply a bigger version of the same panel we’ve already reviewed in the 55″ size. Feed it a great Blu-ray Disc on a properly set-up player, use one of the accurate picture modes, and you’ll see image quality that would have been unthinkable even in multi-thousand-pound studio environments just ten years ago.
Of course, we write this from the point of view as people who look at plasma screens on a daily basis. Given that plasma makes up a maddeningly low proportion of HDTVs sold, we should probably compare it to the wider competition. That’s difficult, because there really is very little contest. Plasma display technology absolutely slaughters LCD (and by extension, LED LCD) in pretty much every picture quality category. The only reasons we can think of to avoid it are if you simply can’t tolerate some aspect of how it operates (some people need a display that’s 100% flicker free, for example; whereas videophile users understand and tolerate a small amount of flicker knowing that this is actually one reason for motion on plasma displays appearing so sharp).
Our review unit had no major uniformity problems; there was a slightly darker band a few centimetres wide on the rightmost edge, but this wasn’t something we felt was a visible problem for the most part. The contrast performance is outstanding, with the deepest blacks money can buy being complemented by whites that, while not at the heights of Samsung’s Series 8 plasmas (or LED LCDs, which are on another level in terms of brightness), are bright enough to produce a rich image. In fact, we managed to achieve a 115 cd/m2 light output from the panel, which is higher than we were expecting from a plasma TV of this size.
The flat gamma tracking that we spent so long in adjusting worked wonders on the image, with tonal gradations looking smooth and natural in content, without any unnatural pools of greyness (to give one example) affecting near-white details. We also didn’t feel, during content, that black details were being suppressed.
We’ve been asked recently to start testing the ability of HDTVs to extract clean film frames out of a 1080i/50hz video source, in other words, to test whether or not the video processor engages film mode for films transferred to the 50hz standard in place for HDTV broadcasting here in Europe (and other parts of the world). All of the test discs on the market are US-centric so don’t include a test sequence for this, so we authored our own test sequence which we’ll be using in reviews from now on. Readers know my opinion on the 50hz format and Europe’s devotion to it already, so I’ll spare the rant, since the unfortunate fact is that European users are stuck with it (all the more reason to invest in a Blu-ray player and watch real 24p movies!)
The answer is yes, the TX-P65VT65B does detect film material inside a 1080i/50hz signal, and it does correctly engage 2-2 pulldown compensation to avoid loss of vertical resolution with this content – for the most part. During actual content, the process worked correctly, although the television was tripped up by a complicated moving wedge pattern. Even in cases like this where the film mode detection fails, it would require very detailed content – probably more detailed than what exists on most HDTV broadcasts – to reveal the resulting jaggedness, because the VT65’s video processor has good suppression of jaggies anyway.
All in all, we really don’t feel there is much that Panasonic could improve with their plasma televisions. Any small quirks present seem to be inherent to the design, would need a radical overhaul, and result in a different set of compromises, anyway. More light output for a more dazzling image would be good (just look at what Samsung have achieved on their F8500 plasmas), but if we had to choose between prioritising light output and prioritising blacks, we’d still pick the latter, because the effect of incredibly deep blacks and whites that are bright enough is profound.
Chroma Format (extreme pixel peeping lesson)
A strangely large amount of online discussion has surfaced concerning which signal format should be sent to flat-screen TVs and projectors over HDMI: YCbCr 4:4:4, YCbCr 4:2:2, or an RGB variant. If this is all greek to you, just know that the numbers (4:2:2 etc) refer to the resolution of the coloured “layers” which make up the picture relative to the black and white base (which accounts for most of the image’s detail). 4:4:4 means that each pixel in the image has its own unique coloured value, whereas 4:2:2 means that two pixels in a line share the same coloured data (to save space). The video on a Blu-ray Disc is stored at 4:2:0, meaning that the black and white luminance layer is full 1920×1080, whereas the two colour-difference layers are effectively 960×540.
A quick skim through forums reveals that the general consensus is always to choose the “YCbCr 4:2:2″ option because this is the closest match for what is actually stored on the Blu-ray/DVD disc. Actually, the best choice depends on the display and the player. So what about the 65” VT65?
The Panasonic TXP65VT65B’s chroma processing is never flawless. There are three main configuration possibilities for getting coloured pixel data from Blu-ray Disc (and other HDTV sources) into the television and out of the plasma panel device. The first is to send 4:2:2 video in. The second is to send 4:4:4 video in but to enable the Viera VT’s “1080p Pure Direct” mode, which claims to keep the pixel data as 4:4:4 internally (it actually doesn’t, but it’s close). The last is to send 4:4:4 video in but to leave “1080p Pure Direct” off, which will involve a conversion to something less than 4:4:4 (4:2:2 maybe?) inside the TV.
In all cases, the TX-P65VT65 has a small vertical chroma resolution limit, and no amount of setup will avoid this (it’s even present in the so-called “4:4:4” mode – which is not actually 4:4:4 due to the limitation). Users can check the chroma reproduction capability with the Chroma Multiburst pattern from the Spears & Munsil test disc. In all cases, the vertical pixel transitions (bottom-right box) are blurred slightly.
With our Blu-ray player (in this case, an OPPO BDP-103EU) outputting in 4:2:2 mode, the vertical coloured details were less visible. Strangely, the Panasonic 65VT65 will also draw some false coloured pixels on the horizontal axis when receiving 4:2:2 video. For example, with the red and blue stripes at the left of the pattern, the TX-P65VT65B displays a single black column inbetween the two. And on the Interactive Graphics layer which appears when you press the BD remote’s middle button (to display the “How to use the pattern” screen), the horizontal transitions in the “Good” example image appear green!
After changing the output mode to 4:4:4 – which means that our Blu-ray player was doing the upsampling of the chroma planes from the 4:2:0 encoded on the disc – the horizontal resolution improved, being nearly perfect. The transition between red and blue was razor sharp – with only a tiny slither of blur. As noted earlier, the vertical high frequency information was still curtailed.
We checked out the last scenario, by enabling [1080p Pure Direct]. This increased the horizontal resolution very slightly, to the extent that it actually revealed some blocking in the reds. In other words, this made the horizontal chroma resolution in the display so good that it revealed (what could be described as) a shortcoming in the OPPO BDP-103 player. However, Panasonic BD players feature advanced chroma upscaling features which avoid this very minor blocking (something we tested) and intelligently smooth it out instead.
Therefore, we can conclude this extreme pixel peeping by saying that arguably the best way to watch Blu-rays on the TX-P65VT65B is with a Panasonic Blu-ray player (or similar), outputting 4:4:4, with the [1080p Pure Direct] mode enabled, and the player’s advanced chroma processing feature turned on. Even the cheapest current Panasonic BD players have this feature, and will outperform more expensive “boutique” players in this minor regard. If you don’t have a player which smooths the chroma channels in this way, then you might find that you prefer to feed the Panasonic VT65 with 4:4:4 video but to leave the [1080p Pure Direct] mode off, which will effectively act as in-TV smoothing of small jagged colour details.
Are you left scratching your head at all this? If so, don’t worry, because we’re taling about the last Nth of performance here! If you’d like to read more on chroma subsampling, specifically with regards to choosing the best mode in your setup, Spears & Munsil have this great article on the subject.
3D
There are no surprises when it comes to the Panasonic TX-P65VT65B’s tri-dimensional performance. Like nearly all of the Japanese company’s plasma-based 3DTVs, it uses a 3-D screen drawing method which curtails uneven greyscale problems (colour tints after calibration), ostensibly at the expense of resolution. That means that very fine diagonal lines can appear jagged when compared to 3D Full HD LCD TVs and plasmas which don’t use this technique, but, in the very small likelihood you have your 3D TV calibrated in 3D mode, you’ll benefit instead from less unwanted tints creeping into shadows (for example).
On the whole, its good news for the relatively unloved extra-dimensional format on the Panasonic VT65. The images are relatively free of crosstalk, fairly bright (you have the choice of using a High panel brightness mode to squeeze more light output from the panel, at the expense of some added dithering noise), and the 3DTV has absolutely no problems with motion judder in the third dimension.
Image Retention
The 2013 Panasonic plasma televisions appear to be more resilient to the plasma bugbear of image retention than the outgoing 2012 models. During our testing, we treated the TXP65VT65B to a good number of non-stop hours on channels such as BBC News, CNN and France 24, all of which contain completely irresponsible solid logos. We could only get it to retain shadows of these images, which faded.
Gaming
We had a blast playing Halo 4 on the Viera TX-P65VT65, thanks to its small video processing delay time, which measured at 41.5ms with the Leo Bodnar input lag tester (41.5ms is a good figure by the criteria of this testing device). Assessed with the high-speed camera method, which we have hypothesised takes into account the subfield drive of the plasma display and how this affects perceived responsiveness during gaming, the Panasonic TXP65VT65B could be said to lag by about 23ms. In any case, it felt smooth and fluid to us – provided we were using the Game Mode, of course. Don’t try it without!
Conclusion
After already checking out the smaller screen sizes in the VT65 range, this 65-incher didn’t reveal any surprises, and that’s absolutely fine with us, because these are arguably the best flat-panel TVs on sale today. Arguably, that’s got as much to do with Panasonic’s high standards (not to mention exclusive display research) as it has to do with the lack of competition, most of which is LCD. There are a handful of good reasons for some users to go down the LCD route (very bright rooms where the extra light output is needed being the most obvious), but put the two side-by-side and feed them the same content, and you’ll see why it’s still plasma or bust for the majority of video enthusiasts.
That effectively leaves Samsung’s excellent plasma panels for Panasonic to compete with (we’ve not been privy to what LG have been doing with plasma display technology lately). Panasonic’s main strengths include their freedom from minor artefacts like floating blacks and brightness pops (Panasonic dealt with fluctuating brightness some years ago), and their world-beating black-level depth. On the other hand, Samsung can boast about dazzlingly bright whites, smoother scaling of standard def images, and lower prices. It’s win-win for video lovers, so check both out, pick the one that best suits your needs, and enjoy.
Panasonic’s TX-P65VT65B is one of the best flat-screen HDTVs we’ve tested. It doesn’t commit any major crimes against video accuracy, so colours and textures appear as-intended, and it features the sort of deep, inky blacks that film lovers crave.
Note: If you’re interested in buying this TV, please support us by considering making your purchase from our advertising partner Panasonic Store Doncaster – call 01302 365760 and ask for Richard, quoting HDTVTest for competitive prices and first-rate service. Follow them on Twitter too for special offers from time to time.
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