L2870U brings HDR together with Brightness Intelligence Plus Technology (B. I. + Tech. ) to gently soften bright areas while keeping dark details crystal clear. EL2870U's simple hotkey switches between 4 levels of HDR and B. I. + modes to balance maximum contrast and vibrancy and fully enjoy the splendid image performance of HDR while maintaining your viewing comfort. The image has a faulty coloration - Go to Picture and Reset Color, and then choose YES to reset the color settings to the factory defaults. If the image is still not correct and the OSD also has faulty coloration, this means one of the three primary colors is missing in the signal input. Now check the signal cable connectors. If any pin is bent or broken off, please contact your dealer to get necessary support. The image is distorted, flashes or flickers- Read the instructions on the link "Adjusting the Screen Resolution" on the CD, and then select the correct resolution, refresh rate and make adjustments based on these instructions. The image is blurred- read the instructions on the link "Adjusting the Screen Resolution “on the CD, and then select the correct resolution, refresh rate and make adjustments based on these instructions. If a VGA extension cable is used, remove the extension cable for the test. Is the image now in focus? If not, optimize the image by working through the instructions in the "Adjusting the refresh rate" section on the link "Adjusting the Screen Resolution". It is normal for blurring to occur due to conduction losses in extension cables. You can minimize these losses by using an extension cable with better conduction quality or with a built-in booster.