chahahc So you are still getting issues even with using the SCT orange. That tells you there is another problem going on. One variable you are never removing from your tests is eye tracking. Is every setup you run 60 hertz refresh rate? So you get tons of motion blur. Sounds like your problem isn't dithering because of the 6 bit panels you are using. What type of panels are you using TN,VA or IPS? You will get slightly different results with each one. Heck your problem could be LED not producing proper blacks/viewing angles pixel arrangement. LED monitor with a black equalizer could be another thing to try. Also OLED/Plasma/CRT to see what kind of results you get with true blacks. Plasma/CRT = No motion blur something that is really hard to achieve on LED and a major source of eye strain. You can get funky results sometimes with Plasma/CRT with windows so be warned. Especially if it doesn't really recognize the screen in the hardware settings. Phosphor is similar to BFI and at low refresh rates can be problematic. That's why CRT was usually good for most people at about 85HZ and above. I think panel type is a big deal and those cheap 100 dollar panels won't cut it for most people. A lot of new panel types are coming out now with low motion blur and incredible over drive. Features that didn't even exist last year. https://forums.blurbusters.com/viewtopic.php?f=2&t=5587
This monitor just got tested by Rtings it's a 240hz and seems to be the best monitor they have ever tested. There was a lot of problems with previous 240hz monitors(1 generation panels)
Here is another one that seems to be really good with reviews and it's just coming out.
https://forums.blurbusters.com/viewtopic.php?f=2&t=5508
https://mobilesyrup.com/2019/07/22/lg-ultragear-gaming-monitor-available-for-pre-order-canada/
This LG I think will be a game changer as it's the first of its kind. Lets wait for reviews but It brings the best of both worlds TN's - Speed with IPS's color accuracy. It also uses LG's new panel which has incredible overdrive hopefully lets see reviews first. This panel just came out and what put in there latest TN panel that I currently use with no issues.
You will also generate different results based on what you are doing. Are you playing games? Just using the Internet? Watching movies?
Good luck in your battle.
I suggest if you have the money go to the store buy a panel make a list of possible problems return and try again. I did this for so many panels. I suspect my main problem is Motion Blur possibly no true blacks on LED. PWM but that is easy to solve. Blue light is a problem but turning down the gamma and brightness can usually bring a monitor into a safe zone as long as it isn't one of those crazy 9 000 000 000 nits monitors.