What do you think of the Dynamic tone mapping in the LG 2018 oleds?
I've been using it because it's on by default and everyone say that it makes the image look better, but it makes kind of difficult to calibrate certain games HDR settings.
I can't speak from first hand experience, as I don't own that display, but I can tell you what I think based upon what I know about image processing.
I personally wouldn't use it as technically in order to tonemap a moving image correctly (without pre-manufactured metadata), you need to know what is coming up so you can scale the shadows, mids and highs appropriately. This change is not only occuring within a single frame, but across a series of frames.
Think about exiting a tunnel ot walking through a dark room to the outside. When it's dark the dynamic tone mapper needs to make a decision about what to do with the image.
Should it lift the brightness in order to help improve visability in the shadows, this however comes at the expense of clipping white detail
Should it make the outside visible , but the inside becomes very dark
Or should the shadow detail be lifted and the highlights reduced to preserve detail, you flatten the image and reduce overally contrast and dynamic range, but maintain detail.
Now the display cannot possibly know what you are going to do next and how should it translate whatever decision it has made the the next action that is appearing on screen.
With movie content you can read ahead and look at what is coming to influence the current part of the image, but you cannot do that with a videogame (without inducing serious latency), so I doub't it's effectiveness.
This stuff is usually done by hand for movies based upon how they want a given scene and it is done programatically for videogames, because the in game tonemapper has a lot of information at any given point about what is the object in focus, your speed of movement and whether or not you are likely to exit that tunnel or not (in Shadow of the Tomb Raider you can occasionally see yourself stepping over a trigger that affects the exposure and tonemapping in exactly this situation)
You'll have come across the same thing with your smartphone camera struggling to decide how to tone map the HDR data of the real world into the very small dynamic range of you screen.
But anyway, back to your TV,
If you see any kind of swelling or pulsing of Dark or bright scenes, then you know that is the Dynamic Tone mapping in action however in a videogame where there is already a lot of tone mapping an exposure adjustment happening from the game engine, then you may not be able to even see it. Because it is a post process on to of the already tone mapped image, it may have the potential to excerbate banding. If it looks better to you, it looks better.
The Dynamic contrast on my Samsung display doesn't appear to actually do anything Dynamically in game mode, it appears to be varying degress of lifting the shadows and mid tones almost statically. If the LG set's behave in even a slightly similar way, then it may be something that you engage if you are in a sub optimal (light) viewing environment.
