Panasonic TX-65GX800: an affordable and well-calibrated Ultra HD TV

Presentation

The Panasonic TX-65GX800 has a 65-inch (approx. 165 cm) VA panel displaying an Ultra HD definition of 3,840 x 2,160 pixels. The manufacturer announces compatibility with all HDR standards, whether HDR10, HLG, HDR10 + and even Dolby Vision, which is interesting in this price range. In terms of the audio system, you have to make do with two 10 W speakers. As for the heart of the TV, it is entrusted to the My Home Screen 4.0 home system.

This television is currently sold for less than € 1,000, and sometimes even much less, which sometimes makes it a very good deal. It is also available in 40 (102 cm), 50 (127 cm) and 58 inch (140 cm) versions at the respective prices of 600, 750 and 800 €.

All the brightness and colorimetric measurements mentioned in this article were carried out with a SpectraCal C6-HDR probe and the CalMAN Ultimate software.

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Image quality

This television uses a VA (Vertical Alignment) type LCD panel. This display technology provides good contrast by effectively blocking light from the backlight. In return, the viewing angles are smaller than on an IPS or Oled LCD television.

We measured a variation in brightness of 65% at 45 °, a little less than on other VA televisions (around 70%), with the exception of very high-end models using an optical filter improving the viewing angles (Samsung QE85Q85R / QE65Q90R or Sony 65XG9505). This is very far from what Oled technology offers (only 25% variation at 45 °).

True Cinema mode provides the most accurate rendering. In this mode, we measured a delta E of only 2. The colors can thus be considered as faithful to those sent by the source. Only a few shades exceed a Delta E of 3, a threshold above which the human eye perceives colorimetric drift.

By setting the TV's gamma to 2.3, the measured curve is stable over the entire spectrum (average at 2.29). The grayscale rendering is therefore generally very good.

By default, the average color temperature is measured at 6,890 K, a value fairly close to the reference value (6,500 K) and above all the curve is stable over the entire spectrum.

With a ratio of 4,620: 1, the contrast is excellent for an LCD TV. However, Panasonic has given in to the sirens of dynamic brightness to improve contrast. The white measured at 150 cd / m² on our target at 35% thus goes to 168 cd / m² on our target containing 1% of white, ie an average of 159 cd / m² on the white and 0.04 cd / m² on the black. This contrast ratio makes it possible to display deep blacks, even in a room without light.

The Full HD version scaled on the left and the native Ultra HD version on the right. [/ Media]

The scaling engine allows you to resize SD, HD and Full HD content so that they display correctly on this Ultra HD panel. This fairly basic engine produces a smoothed image that does not distort the original source and limits the artifacts.

On the motion compensation side, the motor does its best to limit jerks, but it cannot improve sharpness in the absence of a 100 Hz panel. The 50 Hz prevents the insertion of black images via scanning backlight.

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HDR

The Panasonic is one of the rare televisions compatible with the two dynamic metadata formats HDR10 + and Dolby Vision in addition to the classic HDR10 and HLG. Remember that HDR10 + and Dolby Vision are particularly effective on entry-level TVs since they take into account the capabilities of the TV and thus avoid clipping (white saturation).

The Display Tone Mapping used by Panasonic is very good. It perfectly follows the curve up to 55% luminance, then it smooths the signal up to 80% luminance. We would have preferred that Panasonic completely smoothed the signal up to 100%, which represents the maximum capacity of the TV so as not to lose detail in very bright areas. This television does not avoid the phenomenon of clipping with a signal in HDR10 at 10,000 cd / m² used for this test.

The peak in brightness measured at 373 cd / m² does not allow a sufficiently contrasted and dynamic HDR image to be displayed. The Panasonic TV catches up with a good level of black, but it cannot display the dynamics of very bright images.

In True Cinema HDR mode, we measured an average Delta E at 3.4, which results in fairly accurate colors, but which cannot be described as faithful to those sent by the source. This remains above the average of other TVs in this price range, which often display fanciful colors in HDR mode.

The Panasonic 65GX800 only covers 66% of the Rec.2020 space. A rather low figure which does not allow to correctly reproduce all the colors of this space. Remember that high-end televisions are currently content with 70 to 75% coverage of Rec. 2020. So it's not really important at the moment, but it is a good indicator of the quality of the panel and the backlighting system.

The coverage of the DCI-P3 color space is also limited to 78%, a fairly disappointing value since some televisions in the same price range manage to rise to 85% of this space (see TCL 55EP680). For comparison, Oled TVs display more than 90% of the colors of the DCI-P3. It is this space that is still mainly used today for 4K Ultra HD productions.

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Video games

The remanence time measured at 19 ms is very far from that of the best LCDs on the market, like the Samsung QE65Q85R and Sony KD-75XG9505 which go down to 11 ms. It corresponds to that of entry-level televisions like the Samsung UE55RU7405 or the TCL 55EP680 which display a remanence time of 17.5 to 18 ms. We can therefore perceive a trail behind moving objects (ghosting).

As for the delay in display, we brought out our CRT monitor to assess the reactivity of the TV. In the end, this television displays a delay with the display of 30 ms, which represents a little less than two images of delay compared to the source. There is very little lag between the action on the controller and its impact on the screen. However, competitive video game enthusiasts will turn to more responsive models like a Samsung QE65Q90R or an LG 65C9.

Panasonic is one of the few manufacturers to offer a Game Mode available on all image presets (Menu> Image> Option settings> Game Mode). It is therefore possible to benefit from an input lag reduced to 30 ms in True Cinema mode, and therefore to have perfect colors in games.

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Clouding

The thermal signature confirms the use of an Edge-Led backlight system. [/ Media]

The Panasonic 65GX800 uses an Edge-Led backlight system which only has one backlight bar located at the base of the panel. If we did not find clouding problems on the model we tested, the risk is present, because the diffusion filter is fragile and can be damaged during transport. This results in the appearance of grayish spots on a uniform background. Finally, we did not notice any light leakage on our test model; on the other hand, vertical blooming is sometimes annoying, especially on the subtitles, and more generally on all light objects on a black background.

We have measured the average difference in white homogeneity over the entire slab at 11%; a very good figure for a 65 inch LCD model. Remember that below 20% the eye sees no difference in uniformity.

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Ergonomics

The design of the Panasonic TV is very classic. He sports a rather neat black dress for a TV in this price range.

The central foot is imposing (52.5 cm wide by 34.8 cm deep). It is therefore necessary to provide a fairly deep piece of furniture if you also want to install a sound bar.

The edges of the screen are fairly well finished and give the impression that the LCD panel is placed on glass, a bit like high-end Oled TVs (LG E and G series for example).

The treatment of the slab is quite effective against reflections. This TV does not do as well as the high-end models of Samsung - real references on this criterion - and does not equal the Oled models either. On the other hand, it does a little better than entry-level LCD TVs from Samsung like the Samsung UE55RU7405.

In profile, the thickness is measured at 6.6 cm without the foot. The size on the TV stand is in any case always linked to that of the stand, which here shows a depth of 34.8 cm. This TV is therefore just at ease on our benchmark TV stand (160 x 40 cm).

The rear is very classic. The matt black plastic is of good quality. The connectors are placed on the right and the power supply on the left. We also note the presence of holes for hanging on the wall via a wall support to the VESA standard 300 x 200 mm.

The connection consists of three HDMI 2.0 inputs compatible HDCP 2.2 and HDR, two USB ports including a USB 3.0, an optical digital audio output, a component input, an Ethernet port, a headphone output, a PCMCIA port (Common Interface CI +) and TNT / cable and satellite antenna sockets. This television embeds a DVB-T / T2 / C / S / S2 tuner as well as Wi-Fi and Bluetooth.

The My Home Screen multimedia system (here in version 4.0) is derived from Firefox OS, abandoned by the Mozilla foundation in 2018 and from which Panasonic took the source code. If the system is lagging behind Tizen, Android TV and WebOS, especially in terms of the number of applications available, it remains fluid and pleasant to use. This small update still brings some new features such as the ability to take a look at the content of applications like Netflix or YouTube without having to open them. There are a few known applications like Netflix, YouTube, Amazon Prime Video or Molotov.tv, but you have to give up on Spotify, myCanal, myTF1, Bein, RMC Sport and many others. The limitation of the interface is not really a handicap. The user is less dependent on the system of his television and, in this sense, he will be less disappointed when he is no longer updated within 18 to 36 months, because it is often the reality on the televisions on the market. . It is bad for a good for users who prefer a simpler television in order to entrust the intelligent functions to a real multimedia box like the Shield TV or the Apple TV 4K or even a Chromecast Ultra - the latter being more limited, but no less practical .

It takes about 12 seconds to turn on the TV. The next waking from sleep takes 3 seconds. It takes less than a second to shut down and consumes less than 1 W in standby. On this point, it is a flawless for Panasonic, especially compared to Android TVs which wait more than 40 seconds when first started.

The Panasonic TX-65GX800 is content with a very basic remote control. If it offers access to all the features thanks to its many keys, it is still quite dated. Fortunately, the rubber keys are quiet and pleasant to the touch. This remote control ignores the integrated microphone, which is essential for research on the Internet. No key backlight either.

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Audio

The audio system consists of two 10 W speakers. The sound is fine for a TV. Speakers offer the luxury of going down quite low and covering a fairly wide spectrum between 90 and 20,000 Hz. As often, it is still better to opt for a sound bar, a home theater kit or even a PC speaker kit.

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Consumption

We measured consumption at 77 W on our target with a white set at 150 cd / m², a relative consumption of only 66 W / m², much lower than the average of the televisions tested (around 100 W / m²). This TV directly competes with the most energy-efficient models, such as the Samsung QE65Q60R with 66.1 W / m², the TCL 55DC760 with 66 W / m² or the Sony KD-65XG8505 - the most economical TV in our comparison - which only consumes 55.8 W / m². Standby consumption is always less than 1 W.

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Conclusion

The Panasonic TX-65GX800 is a good Ultra HD TV. It displays a quality image, good finishes, a certain ease of use, but like other televisions in this price range, it cannot boast of displaying a beautiful HDR image. For this, we must turn to more expensive models like the Sony 65XF9005 which currently offers one of the best HDR quality / price ratios on this diagonal.

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