LG makes the OLED screens, but Sony, Panasonic and Philips make TVs with better picture quality using those same OLED panels. I don't know whether that's because their picture processing tech is inherently better, or they've had to pull out all the stops to differentiate their version of an OLED TV from LG's, but independent reviews have come to the conclusion that when they all launched, the competitor products to LG were better.
Personally, I would avoid Philips on reliability grounds. I'd be more confident of a Sony or Panasonic OLED, though one person here would strongly disagree about Panasonic.
ON LCD/LED TV screens, there are two basic screen types. There is VA which Samsung and Panasonic uses; then there's IPS which Sony and LG uses. The VA screens do have a narrower viewing angle, but offer higher contrast and a more uniform black. This last feature means you don't see patches brightness variation in the black areas of a picture. There's a good web page showing clear image examples of the pros and cons of each tech. Here's the link:
https://www.rtings.com/tv/learn/ips-led-vs-va-lcd
QLED or Quantum Dot LCD TVs sit between standard LCD/LED in the bulk of the market and OLED at the upper-end.
Quantum Dot is the lighting technology. These are still LCD/LED TVs, but they're illuminated by a special light filtering technique that produces purer colour and a brighter image than conventional LED backlighting. It is marketed as
QLED by Samsung, and
Super UHD by LG, and
Triluminos by Sony.
Quantum Dot TVs have the advantages of high contrast and good black uniformity of VA panels, but with the wider viewing angle and no colour shift that IPS panel TVs offer.
Quantum Dot or OLED?
For rooms when there's good light control, so that on even the brightest days the room can be shaded, then OLED should offer the superior result. But for rooms that have a lot of ambient light for some of the viewing time then Quantum Dot's brightness advantage means that it can still look good.
Getting the best from a TV
As supplied in the box, most TVs don't reach their full picture potential. That's because the manufacturer's picture presents are, at most, an average 'best fit'. They'll never be correct for every single living room where a TV may be installed because every one of those rooms and the equipment the TVs are used with produce a unique viewing environment.
What you see with in-store demos is an extension of this problem with a few other issues thrown in.
It used to be that TVs shipped from the factory were defaulted to Dynamic picture mode. With this setting the TV picture was the brightest it could be, and it had far too much image sharpening, completely over-saturated colour, and a complete lack of any shadow detail. It was the TV equivalent of 'who can shout the loudest' for when the TVs were arranged on display against their competitors. There's a proven reason for this, and it's that our eyes are naturally drawn to the brightest image with the most lairy colour. It's not a natural image, but it does grab our attention.
Dynamic mode has been sidelined. TVs now often come with a menu option to set them to Home or Store viewing mode as part of the initial set-up. That's a step in the right direction for home viewing, but as you've discovered, it still leaves a lot to be desired when comparing on the shop floor.
It comes back to this problem of massed ranks of TVs on display side-by-side. No manufacturer wants their TVs to be overlooked which is what happens when the picture is set up correctly: The contrast is not so high, the colour not so over-saturated, the sharpness setting far more neutral, and the brightness setting gives decent blacks and good shadow detail. It's a less 'shouty' picture, but one that allows more detail through and is far more accurate about representing what the director intended when the programme or film was created.
There are a few different ways that this better level of performance can be achieved at home.
The first is to buy your TV from a company that can demonstrate that they know how to set up a TV properly and where the installer carries the test discs (and player or test pattern generator) necessary to dial in the picture for UHD and HD and SD picture sources. This is not a quick process. To do it justice requires at least 20 minutes per image source plus some set-up and de-rigging time for the test gear. This doesn't happen when the delivery guys are simply unboxing a set, fixing on the table stand and tuning it in.
Second, there's the DIY method. This means buying test discs and the players required to play them, then learning how to use the patterns to evaluate what the TV is doing with each of its picture controls. A basic set up of brightness, contrast, sharpness and colour level can be done in about 10-20 minutes once you've become familiar the test disc. Understanding and adjusting the picture processing modes will take considerably longer. Becoming proficient enough with the test disc to be confident-enough do all the major picture adjustments could take 100 hours. BGetting really good with it takes 1000 hours.
Third, there's buying in this service from a third party specialist. There are custom installation companies where, for a fee, one of their calibration-trained installers can call to your home and provide a TV set-up service. Prices depend on what level of service is being provided. A local travelling distance set-up of the main picture controls including the video processing modes would start at around £75-£120 depending on the number of preset modes being saved. A full image calibration service which includes fine adjustment of the colour tracking controls to the same or higher standards that you see in magazine reviews would be from £250-£400.
Ways of setting your own TV up that don't work
'Somebody else's settings.' This is the standard question that everyone asks when they start to look at tweaking up the performance of any video display: "
I've got a Sonisung XZ8000, what are the best picture settings?" Think about it; if it was that simple, then wouldn't the TVs ship from the factory with perfect settings already stored?
Using someone else's settings, whether from a magazine review or a forum user or even from someone who had the full beans calibration, this just won't work. It comes back to unique viewing environments. The lighting levels and combination of gear makes for a different start point, and so the end figures for the same model of TV will be different in every single room. The other factor is product variation. This is where the combined effects of all the little tolerance differences in components combine to make every single product on the production line subtly different. I did some work with a dealer where we set up the lots of the same model of projector during its production life. This was always in the same room, and the same viewing conditions. Each image calibration yielded subtly different numbers.
I'll take nothing away from enthusiastic owners wishing to share their results through forum sites. They feel they're doing the right thing. However, anyone reading those numbers has no idea of whether that user knew what they were doing or how subjective their final results were. I've been to homes where owners have tried this short cut, and then measured the colour tracking, contrast and gamma for comparison purposes. At best, I've found the improvement over the standard picture settings to be marginal. Often though, some bits are better but other bits are worse. Time spent doing the proper set-up with a test disc invariably produced better results.
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