'4K titles'- meaning what exactly?? Please be more succinct in what content precisely looks good and what does not. Give specific examples if possible, and provide details on exactly which app/connected device/firmware you are using, and who your cable provider is too/connection speeds. (Via wifi or wired?)
I rarely find one setting that is adequate for *all* content. You would benefit from also posting your query in the dedicated AVS thread on that Sammy model. I own the 55" & 60" version of that 4K HDTV and so far, it's pretty decent overall. Some content is not perfect however. The gist of the settings can be obtained in the thread here:
http://www.avsforum.com/forum/166-lcd-flat-panel-displays/2387466-official-samsung-ks8000-ks8500-owners-thread.html
Here's the cache of info:
http://www.avsforum.com/forum/attachment.php?attachmentid=2261392&d=1501470490
Definitely peruse the FAQ before posting(!)
I notice with 4k titles I watch the image appears darker and it doesn't "pop," if that is the correct usage, as other displays I've seen. Even the 4k material on Youtube, mostly scenic imagery, seems to pop more when I am streaming in on my television.
I have a Samsung KS800D and KM85c 4k player with my backlight set to 10. I use the "movie" mode with settings I got from a Cnet article. Am I missing something?

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