Bright HDR Colors after 10.15.4 Catalina Update

I've been having this same issue on my LG 27UL600.

The only way I can reliably get the colors to look normal is to follow the following procedure. Note, this will need to be followed each time the mac wakes up or the monitor is plugged in.

1. Go to System Preferences > Displays > Display and make sure HDR checkbox is checked.
2. Select the Color tab. You should see one or more LG HDR 4K color profiles. Delete them.
3. The color profile should revert to a conventional color space like like sRGB IEC61966-2.1
4. Go back to the Display tab and uncheck the HDR checkbox.

I've noticed that some people say that clicking the HDR button on and off should also achieve the same result. This worked for me occasionally but the number of times I had to switch it on and off varied... a lot.

I had the same issue of color being completely broken upon my upgrade to Catalina. Then I found the HDR checkbox.

By toggling the HDR checkbox, I've been able to get my LG back into SDR mode and looking as it used to. The problem is, when my laptop goes to sleep, the color looks broken again when I wake it up. Toggling the HDR checkbox sometimes resolves the issue. Other times it doesn't.

Being able to actually run the monitor in HDR mode would probably be ideal but it looks terrible currently, so SDR is preferred.

Anyway, it's obviously a bug in the way the OS is dealing with SDR/HDR.

I am using LG UL850-W. After upgrading to 10.15.4 and then met the same challenge. The color become very weird. The fix is also very simple:

1. Close the monitor
2. Unplugged the monitor
3. Reconnect the monitor to MacBook
4. Open the monitor again

Problem fixed.

I've been tweaking my LG 4K 27" over and over since the upgrade. This is a problem. I can get a passable color match (barely) between the monitor controls and the calibration (expert mode) but any video instantly looks like posterized garbage. Was fine before. Flawless. Am patiently waiting for Apple to fix this.

Grabbed a snap (iMac photo a little blurry but still illustrates the problem).

Sorry- this probably doesn't help, but I've been having the same problem. After the update that boolean was checked (I have no idea if it existed or was checked before) and the color on the monitor was way off in the way you described. I was just relieved to be able to get the monitor back in a state where the colors weren't off and burning out my eyes.

I've sort of got the opposite issue. My LG 4K HDR display is now very dull with a slight blue tint instead of being nice and vibrant. The only control on the display itself that works now is brightness and I don't have an HDR box to check in the display settings so I'm stuck with these dull, blue-tinted displays. 😒

Actually now that you mention it, some colors are crazy bright. I just went to Amazon and some of the yellow and orange colors almost look like highlighters. This book that was featured on the home page is practically neon:

https://www.amazon.com/National-Geographic-Kids-1-year-auto-renewal/dp/B002PXW1R0

However the white on the page is really dull and washed out with a blue tint.

Having the same issue with an LG 4k HDR monitor. I've found that checking and unchecking the HDR checkbox in System Preferences > Display multiple times seems to trick the display into showing colors correctly. I know that's not a true solution but it seems to work for now.

Same happening to me after updating to 10.15.4 last night. Horrible blued out screen on a LG 4K monitor. Turning off High Dynamic Range fixes it.

Only happens on a thunderbolt to Displayport cable. Changing to a HDMI cable plugging into a USB-c dongle doesn't have the problem, but the picture quality is crap!

I was quite shocked when I finally updated to catalina. Why would they ruin something that was working in the first place?

Using LG 27UK850w and colors are crazy awful with the default hdr mode. I feel I have to recalibrate the whole thing even after I disabled the HDR option.

I use "Display Menu" in order to run this monitor at the native 5120x2160 resolution without any scaling. With the 10.15.4 update, I can no longer run at 5120x2160 over Thunderbolt 3 - I have to use a USB-C to Mini DisplayPort adapter, and then it works.

Hoping they fix that, the HDR modes in the monitor have terrible color and I can't seem to calibrate around that.

Hi All,

Im connecting to an LG UK-850W from my 2018 15' Macbook Pro and I'm running into these issues. By the same token, my new 2020 iPad Pro has the same issue. I don't need to explain that iPad OS/iOS has significantly less settings and configurations than Mac OS, but it looks like both platforms are running into the issue. Apple any update on patch or fix would be appreciated! We know how nuts things are right now.

I have the same problem with my LG 27UK850. Un-clicking the HDR box helped a lot (thank you for that). I'd also like to know how to use HDR. When checked, the colors are neon with too much blue and most of the settings on the monitor are grayed out (contrast is also set to 100).

Restarting and unplugging and replugging monitor, etc. does not make a difference. Problem started happening once I updated to 10.15.4. Perhaps LG will issue a new driver update?