I have the KS8000.
My settings in HDR:
Backlight: 20
Brightness: 45
Contrast: 100
Sharpness: 0
Color: 50
Tint: G50/R50
Digital Clean View: Off
Auto Motion Plus: Off
HDMI UHD Color: Make sure this is set to On for the HDMI input going to your PS4.
HDMI Black Level Setting: Low
Dynamic Contrast: Off
Color Tone: Warm2
White Balance: 2-point (only changes for me RGAIN -2, BGAIN 4 - this can vary per panel)
Gamma - 0
Color Space: Native
I set the PS4 RGB Range to full. The picture looked pretty a bit washed out on "Automatic" and didn't really have much of the brightness/contrast improvements I'd associate with HDR content. This is apparently known for the Samsung set (there's a thread running around here about it). .Setting the RGB Range to full really brought the beauty of the game out for me.
I had to set the RGB range the same for Deus Ex to display properly on the PS4. Without making that change, Deus Ex looked /terrible/ with a super washed out picture and some strange artifacting around light sources. In that game I had to change the HDMI Black level to Normal which is supposed to match the full range settings on the PS4. In this game, setting to normal washes the picture out. Not quite sure I understand why that's happening here? Either way, Sony needs to look at what the hell is up with the RGB setting and how it plays with certain TV's.
With the settings above though and the changes to the PS4's RGB, I found the improvements to be quite nice. It's not the best HDR implementation I've seen but its a pretty substantial difference over the game in SDR, IMO.
The fact that you're using full RGB on the PS4 and then low HDMI black level means that something is off. You're artificially keeping mismatched color spaces to compensate for other settings that maybe simply do not look good to you.
So no reason to simply ''copy'' what rtings or other websites are suggesting for this TV.
You have dynamic contrast turned off, that kills the colors on this TV especially on HDR. Set it to medium and you'll see a world of difference.
Yet some purists bla bla bla ...every extra filter is evil even if it actually improves the image. Also IMO warm 2 is a yellow filter and with zero sharpness unless you have a native 4K source you can see a lot of blurriness that can totally be removed with a resonable value in the sharpness.
Also outside of game mode you're playing your games in high latency mode especially with HDR on. I've tested the difference and it's noticeable.