And here I was yesterday surprised that there are a lot of 4K HDR TVs for around 400 €...
So what is still not clear, what is the problem with the HDR on these cheaper TVs? Why is it not considered "real" HDR? And what do I have to look for in the specs of TVs if I want to get proper HDR? It's not easy to decide if ads only put there "HDR" and that's it.
So, HDR is basically different brightness for different elements shown on screen. For example, if you are in a cave with pitch black darkness, you should ideally see nothing. Then as someone turns on a torch, the torch should be extremely bright. Or in a scene where there is a tree with shade, sunshine all around and then sun in the sky, the sun should very bright, the sunshine area should also be pretty bright and the tree shade should be not as bright. The sun area of your TV should be such that you hesitate to look at it directly, like in real life. This brightness difference in different part of the screen, based on what that part of screen is showing, is basically- HDR.
And how do we measure the brightness? we measure it in nits, as far as the TVs are concerned. The higher the nits, the brighter the panel is. These cheap TVs, they just basically make their panels in such a way that they cover the absolute minimum brightness requirement to get HDR certified. And that is 300 or 400 nits. So lets say you get a cheap HDR TV. You fire up HDR content and then you cant really see any difference between brightness of the sun and tree shade in the scene and you say- what the big deal is about? What is even HDR? It looks same as usual content.
Then you get a good HDR TV, maybe a LG C9 or extremely high end Samsung etc. You fire up the same content. And how the sun is blinding you, the sunshine is bright and the tree shade looks like real calm place- like if you were looking at all those in real life. Then you will go damn! I dont want to look at the sun, the sunshine is making everything bright. This is great! This is like real life.
Then you play games and random sunshine reflecting on water starts looking amazing. The sunshine peering through clouds is mind-blowing. Then you realize how good HDR makes everything.
There is another twist here though, which is part 2 of my post. And these are black levels.
Black levels are basically how dim a particular area of your TV can go. Taking the example of the cave again. We all have noticed that such dark areas on our TVs are never truly black. They look more grayish. This is because all panels except OLEDs, have a panel behind them which lights up. No matter how neatly the panel tries to light up one area and turn off another area, some light will bleed. So when someone turns on the torch in the cave, the light of the torch will light up areas its not supposed to light up too. Because what the TV is trying to do is light up area where the torch light is, but keep other areas as dark as possible. And due to the way TVs work, some light is bound to bleed in other areas too. There is never true darkness. This is something called contrast ratio/black levels.
And when HDR is concerned, as I mentioned we measure it in brightness. But every bright is bright with reference to something. For example, you put a bright sun on a TV screen where all area other than the sun is also white. Both are bright, sun is brighter. Then you put the same sun in a pitch black area, suddenly sun seems much brighter- even though in intensity its the same as it was on a white background.
This is where OLEDs come in. OLEDs do not have a panel behind then lighting up the screen. In an OLED, each pixel can turn itself on and off. So there is no light to bleed. The torch will light up exactly the pixels it needs to, rest will be pitch black. So technically OLEDs have infinite contrast ratio or perfect black levels. Remember the example of sun we discussed above, against white background? Now that everything else is pitch black, the sun seems oh so much brighter. OLEDs can make everything else pitch black. All other TVs cant. So an LG C9, which is around 800 nits, is often judged as brighter by most people when put side by side with a Samsung Q70, which around 1400 nits but is not OLED. This is purely because the darks are so perfect in an OLED, they pop everything else. The brights look so much brighter, the colors look so much better.
So basically what I am trying to say is
4K HDR OLED from LG/Sony/Panasonic>High end QLED from Samsung>Any shitty cheap Chinese shit which just barely makes the HDR cut.
In fact, the cheap HDR TVs shouldnt even be in the consideration here. If you want the best right now, go for C9 or CX. You wont be disappointed.
