LG 55 B4 vs Dreame S100

The brightness results in HDR materials for LG B4 are very good. It is true that none of them exceed 1000 nits, although the stability of luminance is excellent and looks practically the same in every scenario. The only moment where the tested television performs worse is the last of the scenes, although this should not be surprising. Large frames filled with a lot of white have always been, and probably will continue to be, somewhat of a weakness for OLED televisions. However, the combination of perfect contrast, black levels, and brightness of LG B4 allows for a full experience of the HDR effect. Additionally, the incredibly high coverage of the DCI-P3 colour gamut deserves recognition, reaching 99%. This makes the colours look incredibly vivid and striking.

The Dreame S100 is a relatively bright television. In movie mode, the brightness we measured reached around 600 nits. This is a really good result, although not the highest when considering the competition at this price point. In fullscreen scenes, it is evident that the television can produce an image that impresses with its brightness. Unfortunately, when more complex scenes appeared on the screen, the local dimming algorithm in this model primarily focused on maintaining the deepest blacks. However, this came at the expense of HDR performance – and in a drastic manner. In such scenes, the brightness of bright elements dropped below 100 nits, which is a frankly tragic result, far from any HDR effect. One can improve this aspect, but not without a "however." It is simply necessary to change the local dimming setting in the television's menu, but then the blacks in such scenes simply become grey. It's a pity that Dreame couldn't better refine the local dimming algorithms, and the S100 is another example that the sheer number of local dimming zones does not always translate to a better image. As a consolation, it is worth adding that the Dreame S100 is advertised as a "QLED" type television, although in reality it uses a PFS LED filter. As a result, the colours are appropriately saturated, and the colour gamut coverage of DCI-P3 we measured exceeded 94%.

The best factory mode prepared by the manufacturer is "Filmmaker," which is exactly what we used throughout the entire testing procedure. We must admit that the unit we received out of the box had quite good colour reproduction. The biggest problem in both SDR and HDR content turned out to be white balance. In the former, a strong red hue was evident, causing the displayed image to have a pronounced yellow tint, particularly noticeable on skin tones and whites. In higher quality materials, this colour was also accentuated, but due to a lack of blue, there were also signs of green visible. Apart from these issues, we also encountered problems with grayscale and the colours themselves.

We tested the Dreame S100 in 'movie' mode and we definitely recommend using this setting for watching all types of content. Interestingly, within the deeper settings of the television, we also find a dedicated 'Filmmaker' mode, which is now available from almost every manufacturer. However, in the case of the Dreame S100, we do not recommend using it – it blocks all settings related to the picture and does not allow for any configuration in the menu - even motion smoothing. So, how do the factory colours of the S100 fare? Not too badly, but also not the best. The television itself was quite heavily tinted with blue components, which is clearly visible in our white balance measurements. This made the picture artificially brightened, and the colours had a slight bluish tint. This is confirmed by the Color Checker palette, which showed how the colour samples tend to drift towards blue, generating quite significant colour errors. The picture in HDR mode looked definitely better, where the colour errors were not as prominent, although they still fell far from perfection. Here, the white balance was also shifted too much towards blue, causing considerable errors in colour reproduction.

LG B4 has been providing very advanced calibration tools in its televisions for years. We can even say that as the only manufacturer on the market, it allows for such deep intervention in image adjustment. It is thanks to these tools that we were able to calibrate the device so well. Evidence of this is the extremely low deltaE errors, which can be said to be at a reference level. Both SDR and HDR materials now look exactly as intended by the film director. It is no coincidence that televisions of this brand are most often used as preview screens for various graphic or post-production studios.

The Dreame S100 has proven to be a device very amenable to professional calibration. In its menu, we found a plethora of advanced options that allowed us to effectively correct factory errors. Thanks to advanced white balance correction – both in SDR and HDR content – we completely eliminated the excess blue components. The image immediately became much more natural and pleasant to the eye. After fully tuning the colours, the errors in the Color Checker test dropped below Delta E values of 2-3. For the average viewer, this means that any colour distortions have become nearly impossible to perceive with the naked eye. This is truly a pleasant surprise, as new brands in the television market often encounter significant issues with the correct implementation and functioning of sliders in the calibration menu. Here, everything worked as it should. The only thing we must criticise is the way the television manages its brightness in HDR. Due to the specific nature of the local dimming algorithms, anomalies can be seen on the EOTF curve we measured. Where high highlights should appear, there is a slight boosting of the curve above the reference line. In practice, this causes an unnatural brightening of some of the brightest elements in films or games. Despite this minor flaw, professional calibration brings about a huge, very positive change in this model.

In this paragraph, we will take another look at the function for smoothing tonal transitions, but we will also check how the television handles lower quality material. As we have managed to verify, the setting responsible for smooth gradation works quite efficiently, although it has its weaker moments. Just as the function works correctly in SDR content, it becomes rather useless in HDR content. Even at the lowest of the options, it blurs essential details, which is why we advise against using it.

The image scaling on LG B4 is rated rather moderately positively. Although there is no edge doubling, the image itself is naturally "soft." We can change this by adjusting the sharpness slider.

For scaling and digital processing in the Dreame S100, the technology that the manufacturer proudly calls Dreamind™ Pro AI is responsible. However, it must be clearly stated that this is not a proprietary processor, but merely a marketing name for a chip made by MediaTek – more precisely, the MT5889 model. Unfortunately, we are talking about a rather outdated unit, from a time when MediaTek lagged significantly behind the competition in terms of performance. This unfortunately has a direct impact on the image as that is what this chip also deals with. The upscaling in the S100 is quite mediocre, and the processor has a tendency to heavily and artificially sharpen edges (fortunately, this can be somewhat tempered with the sharpness slider in the menu). In the options, we also find the "Contour Smoothing" feature, which theoretically is supposed to improve tonal transitions. In practice, it offers almost no improvement – setting it to any level rarely eliminates visible banding of colours, but it can unnecessarily blur elements of the image that should remain sharp.

A separate issue is the phenomenon of overscan (cropping the edges of the frame), which is noticeable here practically all the time. Although there is an option to set the screen to display the full frame in low-resolution materials, this requires activating the previously mentioned Filmmaker mode. And as you know, this mode completely blocks the adjustment of any other sliders in the picture menu. In our test tables, we marked that the television offers an option to disable overscan, as technically such a function exists in the system – however, in everyday use, when maintaining sensible image settings, you will not be able to take advantage of it.

The maximum refresh rate that we can set on the LG B4 is 120 Hz. This is the absolute minimum for those requiring high image fluidity. The manufacturer has implemented a multi-step motion smoother called "TruMotion". It has been divided into two separate sliders adjusting the sharpness of moving images (De-Blur) and jitter (De-Judder). Both sliders can be set in the range from 0 to 10, with each degree affecting the level of fluidity, so everyone can find their golden mean.

The LG OLED B4 panel features an average response time of 0.1 ms (which directly results from our measurements), allowing for an incredibly clear image, unattainable for LCD televisions, whose response times can be as high as several milliseconds. This is clearly evident in the pictures from the "UFO Test", showing no trail following the object.

When it comes to motion fluidity, the Dreame S100 performs really well. It features a panel with a refresh rate of 144 Hz, although in reality, the vast majority of people using it in a traditional way will still be limited to 120 Hz (as this is the maximum supported by today's equipment apart from PCs). Thanks to the high refresh rate, the image in motion remains really sharp, largely thanks to the well-functioning MEMC smoother. In the menu, we find predefined modes that allow the television to efficiently generate artificial frames, which effectively improves the fluidity of dynamic sports scenes, but also eliminates image stuttering in film and series materials recorded at 24 frames.

The LG B4 television is equipped with four fully-fledged HDMI 2.1 ports with a full bandwidth of 48Gbps. All features that are identical to this standard were activated without any issues, and throughout the entire testing process, they did not cause any problems. The combination of such extensive functionality and low input lag suggests that the tested television is truly made for gaming. This is not surprising, considering that the manufacturer has always placed great emphasis on this. Therefore, we can enjoy both the properly implemented HGIG mode and gaming in Dolby Vision with low latency. This pairing will certainly attract the attention of all passionate gamers for whom quality is paramount.

An additional standard in televisions from this Korean manufacturer is the implementation of GameBar, allowing for quick adjustment of settings "on the fly," without the need to exit the game. It also enables image adjustments for individuals with visual impairments, which is a very nice touch. Another important piece of information is that when VRR technology is enabled, we will not experience a drop in contrast. This is thanks to the construction of the panel and the lack of conventional backlighting. However, it is normal for shades of grey to flicker slightly; nevertheless, this is a characteristic feature of this function regardless of the manufacturer or television.

In summary: the LG B4, like all of the manufacturer’s OLEDs equipped with 120Hz panels and HDMI 2.1 ports, creates a harmonious whole with the console. In practice, this is a comprehensive television, and if we expect the highest possible efficiency in gaming, B4 will be the ideal choice.

The Dreame S100 seems almost like the perfect screen for a gamer. The television is equipped with 2 HDMI 2.1 ports with a bandwidth of 40 Gbps, which means that functions like automatic game mode (ALLM) and variable refresh rate (VRR) ranging from 48 to 144 Hz work seamlessly on consoles. It also features a well-designed gaming panel (Game Bar), allowing users to continuously monitor important parameters—from active picture modes to the number of frames rendered by the console, and even the option to add a crosshair in the middle of the screen. All of this looks great on paper; however, the biggest problem with the S100 is the implementation of HDR mode in games. The television does not have the HGiG format implemented correctly. As a result, an unsuspecting user may incorrectly configure the console when first using the screen. Poor configuration can lead to an image that is too dark or too washed out (as a guideline: we suggest setting the brightness in the Xbox console menu to around 600 nits, and in the PS5 to 12 clicks). The Dolby Vision format also proves problematic, as it often would not activate at all between the XBOX and Dreame S100. And when it was finally managed to be activated, playing was not possible due to a very high input lag often exceeding 100ms. If the manufacturer can improve the HDR issue in games via an update, the S100 will be truly excellent hardware for gamers. For now, however, compromises need to be accepted.