• Abstract

  • Severe eye strain, I know it's fixable with one button, but don't know which

brvideo All monitors and TVs comes with a secret service menu that is accessable by a secret code. Some of them comes with the possibility to low down the nits of the backlight by controlling the voltage or current that is applied to the source of light.

    brvideo In these old LED TVs that initially hurts my eyes and skin, I solved completelly this issue by lowering down the backlight settings to the minimum level.

      I'm in the process of borrowing a Window laptop so I can see if I have similar issues with it's screen and my monitors. I'm guessing not as I have had WIndows machines at the office for years with no problem, but we'll see.

      In the meantime, I wanted to try and refocus on the specifics of my iMac Pro issue. While it's clear that I am one of the unfortunate who a sensitivity to some specific type of computer display phenomenon, I also know that I was able to use these machines with the same existing software and operating system without any issue at all for years until a week or so ago. My goal is to revert the machines back to that state rather than go down a rabbit hole of eye diagnostics. I've worked in broadcasting and computer training my entire career and have only experienced these eye strain issues with these two machines, which until about a week ago, I had no issues with.

      To review, I originally had a severe eye strain issue with my 2017 iMac Pro. Using some technique that I can't remember (possibly SwitchResX, terminal commands, memory resets), I succeeded in eliminating the issue entirely. But when I recently opened the System Preferences on the iMac Pro, went to the Display tab, held the OPTION key and clicked the Scaled radio button to reveal the current screen resolution setting, I instantly noticed three things: #1 the colors got more vibrant #2 everything got slightly brighter #3 the text and icons got crisper and more defined. The size of the text and icons did not change. It was at this point that the eye strain instantly returned. Also, when I hook up external non-Retina monitors to the machine I still have the eye strain. I'm trying to figure out what these specific clues tell me about where the problem probably lies and how to get it back to the way it was. What adjustments can I make that will make the colors less vibrant and the text less crisp? So far, flipping through the various color profiles hasn't done it and all attempts to turn off dithering/font smoothing using either terminal commands or third party software haven't seemed to change anything. With respect to dithering/font smoothing, It's literally like they aren't doing anything at all…I see no difference visually, let alone eliminating the eye strain issue. You'd think that even if it didn't resolve the eye strain issue, I should see a visual difference when attempting to turn off smoothing/dithering. I've also used SwitchResX to change from Billions to Millions of colors and to choose only non-HiDPI resolutions.

      Logically, when I held OPTION and hit the SCALED radio button, the purpose of that action is to show you all the possible resolutions that the computer can offer. When you don't hold OPTION and just hit SCALED, it just shows you a few options. So when I executed that keyboard move, i'm guessing that it changed whatever manual overides I made to fix the problem, and forced the screen back to only those resolution configurations that are pre-established in the Mac OSX, mostly likely to the one that most closely mirrored the pre-existing non-eye strain configuration I had, since the size of the text and icons did not change, just the crispness and colors, both of which got more intense.

      One more clue. When I Screen Share my iMac Pro to my Plasma HDTV via Apple TV via HDMI, I still feel the eye strain on the HDTV showing the iMac Pro Desktop. Everything is slightly less crisp since it's a TV and not a computer monitor, and the colors may also be a little less vibrant, but the problem persists.

      So any ideas on what to try to put it but it back the way it was?

      Thanks.

        RobC

        If you mean make the screen motif mostly black, then yes.

        • RobC replied to this.

            brvideo Not really, I was talking about the option that you have at settings / screen /Night Shift

                a year later

                brvideo I have a similar issue where I get an instant headache when looking a apple screens, and get terrible headaches in the center of my forehead. I downloaded SwitchResX and changed the resolution to 1536x960, 59.94 Hz with HiDPl disabled. I also changed the color setting from "billions of colors" to "millions of colors". These changes seem to help quite a bit.

                  8 months later

                  I have been wanting to explore this matter further, as it seemed to deal with the issues of overbearing whites and harsh contrast on macOS which seem to affect others here as well. It looks like @brvideo has not been around in some time, but I would love to analyze his SwitchResX preferences files and the terminal history in ~/.zsh_history (from the time he got it working) to see if they would give us any leads.

                  Speculating about what the Displays preference pane would theoretically touch (when the inadvertent reset occurred), the following items came to mind: resolution, refresh rate, arrangement, color depth, color profile, and possibly HDR-related settings. Notably, the setting appeared to have a visual effect early in the boot process, suggesting that the setting was persistent in NVRAM. Noting a few interesting facts about the good settings in the story, 1) they appeared to require a reboot to go into effect, and 2) they were persistent through updates (until the interaction with the display settings), although it was not clear whether these were minor updates or if they included major macOS version upgrades.

                  Do any further ideas come to mind? To me, this sounds like a color profile or backlight setting issue (rather than something like dithering), or (less likely) related to the refresh rate. I have noticed that on several of my Macs, during the boot process the Apple logo will shift brightness a few times (some of which are more comfortable than others), so I wonder if he had previously managed to disable some part of the display initialization.

                  thorpee This would work for a little bit after a fresh install of of Big Sur. I did however notice after I installed and opened some apps it would cause eye issues across the whole OS and I would have to wipe the whole mac and do the steps above again to get it right. I made mental notes of which apps did this and not to use them.

                  This is quite interesting, counter-intuitive as it sounds. My problems began with a 2021 MacBook Pro 14-inch mini-LED XDR, but interestingly, when I got rid of it and used the Migration Assistant application to move my data back to my (previously safe) Intel Mac hardware, the strain seemed to follow albeit to a lesser extent. When I happened to boot another disk with a clean Monterey installation on that same computer, it looked "calmer" than my main Monterey environment, making me wonder if some strain-inducing setting(s) were migrated back with my data (although plausibly, my condition could just be deteriorating).

                      macsforme maybe we can take a color profile from previous/safe versions and put them in the problematic versions?

                        macsforme You could use this command and start it before launching the display extensions to get a feel for what things it reads and writes. It's a lot. It even lists what plist values it uses. I actually think I saw some unknown font smoothing values there as well.

                        log stream --predicate 'composedMessage CONTAINS[c] "DisplaysExt"' --info --debug

                          dev