LG C1 (OLED55C1) 4K OLED TV Review
- Superb out of the box accuracy in Filmmaker Mode
- Reference level calibration results
- Superb HDR accuracy
- Dolby Vision IQ
- Dolby Atmos
- Excellent just above black performance and fade to and from black
- Excellent gaming performance and features
- Very low input lag
- Very good motion
- WebOS 6.0
- New remote
- Good build quality
- Excellent value for money
The Not So Good
- No HDR10+
- No DTS support
What is the LG C1?
The LG C1 is the sweet spot in the 2021 OLED TV line-up and offers all the features you could possibly need, mixed with excellent image quality and the most up to date gaming features. I have already reviewed the 65-inch version of the C1 where I discussed in-depth details on performance which also apply to the 55-inch we are reviewing here.
Aside from this 55-inch model, the C1 is available in screen sizes ranging from the 48-inch (OLED48C16LA), 55-inch (OLED55C16LA), 65-inch (OLED65C16LA), 77-inch (OLED77C16LA) and a whopping 83-inch (OLED83C14LA).
The C1 supports almost all of the HDR formats including HDR10, HLG (Hybrid Log-Gamma), Dolby Vision and Dolby Vision IQ, it doesn’t support HDR10+ or HDR10+ Adaptive, but given the lack of content in that format, we don’t see that as a negative. Also available on the C1 is the excellent Filmmaker Mode which is designed to match the industry standards so you can view content as it was mastered and intended to be seen, without the need for a professional calibration. We will test if that is the case in the measurement section of this review.
In terms of gaming, LG has partnered with NVIDIA and AMD to make LG OLED TVs the only G-SYNC and AMD FreeSync™ Premium certified TVs available to date. There is also the new Game Optimiser set up menu and there are four HDMI 2.1 (40Gbps) inputs with support for 4K/120, HFR (High Frame Rate), VRR (Variable Refresh Rate), ALLM (Auto Low Latency Mode) and eARC. We also have HGiG (HDR Gaming Interest Group) settings available for HDR gaming. So all in all, the C1 is an excellent choice for gaming, with an input lag measured at 12.5ms in 4K/60 and 9.5ms using the Prevent Input Delay setting (make sure you have Just Scan on in the aspect ratio menu).
So is the LG C1 the best all-rounder for 2021? Let’s find out!
Design, Connection and Control
The old adage of ‘if it ain’t broke don’t fix it’, certainly applies to the design aspects of the C1 which are identical to the recent C Series models from the last few years. The panel is slim and with an almost bezel-less design to the front with a slightly larger area to the rear bottom of the panel which houses the speakers, connections and electronics. The stand design also remains the same with a long, slick, metal face which aims the audio out to the listening position from the downwards firing speakers.
The connections are around the back and are sideways and backwards facing. The sideways line-up features a CI slot, three HDMI ports and a USB. Rearwards is another HDMI, two USB slots, an RF and satellite antenna, a headphone and audio output, digital audio out and a LAN port.
... ‘if it ain’t broke don’t fix it’, certainly applies
There is also built-in Apple AirPlay 2, Bluetooth and dual-band Wi-Fi. All four HDMI ports are HDMI 2.1 (40Gbps) accepting 10bit 4K/120 4:4:4 signals and compatible with Dolby Vision, HLG and HDR10. HDMI port 2 is eARC/ARC compatible.
For 2021, LG have introduced a new remote control design with a longer body and new direct access keys. It does however continue to feature the excellent magic remote features with the cursor onscreen and motion control. I really like the new design and the remote still fits neatly in the hand and is easy to use.
Out of the Box
As we did with the 65-inch version we factory reset the LG 55C1 and then measured the picture presets to find which is the most accurate to the industry standards, out of the box, so we can view content as it was mastered and intended to be seen. Like all recent LG OLED TVs, the best preset for this is Filmmaker Mode (FMM) which switches off all unwanted processing with accurate colour and white balance retained. ISF bright and dark modes are also accurate for colour and white balance, but they do have picture processing switched on as a default, so you would need to switch these off manually. Filmmaker Mode is a one-button press solution that is free from any tampering from processing. It has no motion interpolation switched on and hits gamma BT.1886, D65 white and Rec.709 colour for SDR and BT.2020 colour, and ST.2084 PQ EOTF for HDR. On the C1, the out of the box OLED Pixel Brightness in FMM is set to 25 which equals 100 nits for dark room viewing, however, you can adjust the brightness to match your room conditions.
Looking at the greyscale results, we can see that the tracking is very good indeed with just some slight drops in red energy and a very slight green rise, but these are insignificant and invisible to the human eye. This is because our DeltaE errors are two and under, which is well below the visible threshold. Gamma is also good with very few issues and on the graph there is a dip to a brighter 2.2 at 90% brightness, but again this is not actually visible with viewing material. As such, FMM is very accurate out of the box for the white balance.
Moving to the Rec.709 HD colour gamut coverage, we can see that the results are very accurate with some very small, invisible errors in the graph. Red is slightly oversaturated and magenta has a slight hue error towards red, but as our DeltaE errors are an average of 0.9, these are invisible when watching TV and film content. FMM is again very accurate and even with some variance between panels, it has proven to be very consistent on LG models we have tested so far.
The 55-inch C1 features an array of calibration controls within the menu system as well as Calman AutoCal to help easily dial-in accuracy. For this review, we manually calibrated the set, but we also tested that AutoCal works as intended, and it does.
Looking at the greyscale results you can see that we managed to obtain superb accuracy to reference levels for the greyscale and gamma. There is not much else we could do with the results here as they are more or less perfect.
Moving to the calibrated Rec.709 colour gamut results, we can also see superb accuracy here with no major errors at all. Once again, LG has made it very easy to dial in reference levels of accuracy to the industry standards.
This year the G and C series models from LG are different in terms of picture quality, where in previous years it has just been cosmetic differences that has separated the series line-up. This year the G series has the OLED Evo panel and electronics which boasts higher peak brightness as well as a more relaxed ABL circuit. The C1 is not equipped with the same picture brightness, although some will share the Evo panel as the G1, they are not set up to take advantage of them. The full explanation is in the 65-inch C1 review if you are interested in finding out more.
The C1 was measured in the Filmmaker Mode HDR settings which are the closest to ST.2084 PQ EOTF, D65 white point and BT.2020 colour gamut for HDR10 playback.
Measurements at the various window sizes up to 100% white field yielded a peak brightness of 707 nits on the 10% window and 124 nits on a full 100% window. This is within the range of the 65-inch we tested a few months ago and is what we would expect from this model and panel.
Another important part of an HDR image is the PQ EOTF tracking to ST.2084 and the tone mapping employed. Looking at the PQ EOTF measurements, we get results that are almost identical to the 65-inch review sample, with the 55-inch we are testing here tracking the PQ EOTF correctly before a gentle roll off and then a hard clip at the peak brightness of 707 from around 80% brightness. The C1 employs the same tone map for 1000 and 4000 nit mastered content.
Wide colour gamut performance to the DCI-P3 colour gamut within BT.2020 is also superb with excellent saturation tracking to most of the important points within the gamut. There is a slight undersaturation of green and yellow at 100% and a slight oversaturation of red at 75% brightness and saturation, but overall the performance is excellent for wide colour reproduction.
We measured BT.2020 at 72% XY and 78% UV with P3 coming in at 96% XY and 98% UV.
The C1 is a direct replacement for the outgoing CX model sharing the same design and stand. In terms of features, both models have the same major features of HDR10, HLG and Dolby Vision with IQ present and correct, but the remote control and WebOS smart TV system have been updated on the C1 along with the full line-up for Freeview Play.
As with the 65-inch we tested a few months ago, the C1 has all the features you would expect from the mid-range premium OLED model with superb build quality and design. It is not a huge leap forward when compared to the C9 or CX models and if you own one of those TVs and are considering an upgrade, the C1 doesn’t offer enough of an improvement in my opinion to justify a change. However, if you are new to OLED or looking for an excellent all rounder, the C1 is hard to beat at the price point.
Panel uniformity was excellent on our review sample with no major issues such as dirty screen effect, vignetting or banding. There is a very slight colour shift to cyan at the edges of the screen when viewed from a wide-angle but, when straight on with the TV, I didn’t see any obvious issues with tint. With just above black at 5%, we had some lightly visible bands on the test patterns towards the centre, which is the same as we had with the 65-inch during testing. However, as with the 65-inch none of these issues was visible with normal TV and film viewing on the 55-inch, even in a dark room and with dark scenes.
Video processing from the α9 Gen4 AI-enhanced processor was excellent with upscaling and we saw no issues at all from 576i, 1080i and 1080p content scaled to the panel resolution. Lines were straight and clean with no edge enhancement or ringing and there were no artefacts present. Motion was also excellent with no induced judder and correct 5:5 pulldown with 24fps material with TruMotion switched off.
4K content was dripping in detail and depth
You can also use the 120Hz Black Frame Insertion (BFI) which has four settings: Low which applies a 70% duty cycle; Medium which applies 50%; High which applies 50% plus black frame insertion; and Auto which automatically applies an optimised duty cycle based on real-time content analysis. Low and Medium work the best without any noticeable flicker, but it was also noted that there was no apparent improvement in motion resolution. Using BFI will also affect your image brightness, so you should avoid using it with HDR10 content as you will lose around 100 nits of peak brightness.
Within the TruMotion menu is a new setting called Cinematic Movement, which replaces Cinema Clear. This mode aims to add frame interpolation without causing Soap Opera Effect (SOE) to be visible as it prioritises real frames while blending those it creates through interpolation. This is supposed to make motion smooth but with a natural look and for some material it certainly works well. Personally, I cannot get on with any interpolation and notice it being added straight away, but for many users this setting will work well for them and reduce instances of image judder. With TruMotion switched off I also didn’t notice any frame skipping with 50Hz broadcast material, even those programmes with fast-moving cuts looked smooth.
Just like the 65-inch, the just above black performance is excellent on the C1 with a visible improvement over the CX and C9 TVs. Where we had issues on the CX with black flashing and floating blacks within tricky scenes, such as Stranger Things where Eleven is within the Upside Down and walking in a pitch black void and in water, these are no longer seen with the C1. We also didn’t notice any issues with excessive black dither from normal viewing distances, making fade to and from black look exceptionally fluid. Even bit starved content looked reasonable with shadows holding up well without excessive image artefacts.
With SDR content, the C1 is exceptionally good in Filmmaker Mode out of the box and in calibrated modes. Film material looks cinematic with excellent colour reproduction that looks vivid and natural, with excellent life-like skin tones. Black levels are strong with shadow detail that is visible and adds depth to the image, creating some exceptionally breathtaking images that we have come to expect from OLED. There were no obvious issues with motion or upscaling of good quality content and 4K content was dripping in detail and depth. The C1 is an excellent performer with SDR content looking exceptionally detailed and cinematic.
... even those programmes with fast-moving cuts looked smooth.
Moving to HDR10, and Dolby Vision just heightened the performance available from the C1 with excellent sharpness, detail and depth, mixed with bright and vivid wide colour performance. Blacks are again the strong point of OLED with superb dynamic range and just above black detailing that brings images to life. Dolby Vision content really benefits the C1 with peak highlight details visible within the brightest reaches of the image, but not at the cost of overall image brightness, the dynamic metadata and tone mapping is excellent. While the LG G1, Sony A90J and Panasonic JZ1500 can go that little bit brighter and show just a little more detail in the highlights, in isolation the C1 gets very close to that level at a lower entry point.
The LG OLED55C1 is a superb gaming TV with excellent contrast and dynamic range mixed with very good HDR. The C1 is compatible with VRR (Variable Refresh Rate), ALLM (Auto Low Latency Mode) and has an HGiG (HDR Gaming Interest Group) setting under the Dynamic Tone Mapping sub-menu in the Game Optimiser mode. There is also support for G-Sync validated by NVIDIA and on top of that, there is support for AMD’s FreeSync VRR.
The new Game Optimiser menu settings allow direct access to the best presets for your gaming experience giving you choices for Game Genre, Black Stabiliser, White Stabiliser, Fine Tune Dark Area, VRR and G-Sync as well as settings to reduce input lag further using the Prevent Input Delay setting. I measured the input lag at 12.5ms in 4K/60 and 9.5ms using the Prevent Input Delay setting, which is identical to the 65-inch C1.
... if you are new to OLED or looking for an excellent all rounder, the C1 is hard to beat at the price point.
As we found with the 65-inch version of the C1, the new smart TV system, WebOS 6.0, is a big change from has gone before. Gone is the launcher bar at the bottom of the screen, replaced with a full-screen smart TV menu system which fills the entire viewable image area. This new layout has stacks of boxes with three large, top blocks, and below is a horizontal list of Trending Now features, and there’s a horizontal app list where you can highlight and choose to launch an app from a large choice including Apple TV+, Disney+, NOW, Prime Video, Netflix, YouTube, BBC iPlayer, ITV Hub, All 4 and more. The next layer of tiles is the Home Dashboard with the connections you have access to, including AirPlay and then there are a series of further layers highlighting available content in other applications. We found the system works well with no slow down or crashing while opening applications and switching between them was also effortless. I personally miss the launcher bar, but the new layout does work as intended.
The menu system has also seen some changes that existing LG users may find strange to begin with. However, the layout is neat and functional while remaining intuitive to use.
LG C1 (OLED55C1) 4K OLED TV Review
As we found with the 65-inch version of the C1, if you already own a C9 or CX it is not worth the upgrade to the C1 given the small incremental differences, mainly fixing some black flashing and shadow detail, changing the menus and adding a new WebOS system and remote control. However, that is not to say the C1 is not a great OLED TV, it absolutely is for those not already invested in recent C series models.
The strength of the LG OLED55C1 is its all round ability to cover a number of bases with superb picture quality, excellent smart TV system and class leading gaming features. It offers many things to many users and performs at an extremely high level in all the disciplines.
The C1 does all of this while also offering excellent value for money given the feature count and performance levels vs. current pricing, making it a true Best Buy in our opinion.
Contrast/Dynamic Range/Black Level
SDR Picture Quality
HDR Picture Quality
Picture Quality Out-of-the-Box
Picture Quality Calibrated
Ease of Use
Value for Money
The games console used in this review was kindly supplied by our gaming partner Smyths Toys Gaming, the No.1 choice for next-gen Gaming