I have the same symptoms like other users of this forum. When looking at newer displays (from 2016 on) I have aching, burning and tiring eyes with increasing tension to nausea and hypersensitivity. Headache has also increased recently. After just a few minutes of using, it often takes hours/days until the feeling of pain/adjustment has subsided completely. I suspect the reason of the symptoms in the area of ​​temporal dithering/ FRC and/or font rendering. I've done a lot of research and tests and I think I can rule out a lot of other causes like PWM or LED hyper-sensitivity. Windows 7 is a save system for me.

If sitting in front of a save system and connection with VNC to a system which causes strain like Windows 10. The eyestrain/headache symptoms are triggered. I have problems to understand why? VNC just transfers compressed images, i set the refresh rate to 1 second, so in theory no dithering can be applied. If I connect to a system that is save, no symptoms are triggerd. So I can exclude that the VNC client tool itself perfoms dithering.

Any ideas?

  • diop replied to this.

    Markus This lends to my theory that this whole issue is solely pixel movement/rendering.

    The wiki for VNC shows it uses the RFB protocol - "Although RFB started as a relatively simple protocol, it has been enhanced with additional features (such as file transfers) and more sophisticated compression and security techniques as it has developed." Although it may not be using PCoIP (1-1 pixel data as the host) it may be using some form of lossless compression.

    Also as you mentioned, setting up a 'good' OS as host doesn't cause you issue, but a 'bad' OS does.

    I've recently got a new Dell U2419H - after using it for over a month including two weeks on my known good machine, I can confirm it's 100% comfortable for me to use and I've had no ill-effects. I can rule out LED as the culprit too, as well as PWM to an extent.

      diop Using RDP instead VNC feels the same. Client on save system to save host system - no symptoms. Client on save system to bad host system - symptoms. Your Dell U2419H display ist only free of symptioms for save systems, or?

      • diop replied to this.

        Markus It's only comfortable with 'good' systems, so the monitor is fine to use but dependent on the video source.

        5 months later

        It would be great if other people can test if they have symptoms connecting from a known good device to a triggering device using and RDP or VNC connection.

        • diop replied to this.

          ODROID-C2: terrible eyestrain via HMDI, but no eye strain at all when connecting via VNC (official client) from my Android smartphone. I can even open Firefox without eyestrain. I use an older client version so can't say if new clients introduce eyestrain.

          That is over a virtual display ( which is the regular VNC mode).
          I don't know if using x0vncserver, which uses the same screen as an attached monitor, would make a difference.

            Markus I was going to recommend Shadow PC, but it looks like they aren't offering slots until later this year/next year. I had exactly the same symptoms as being in front of a bad PC, I couldn't believe it.

            KM That is over a virtual display ( which is the regular VNC mode).

            I can connect to my bad devices using TeamViewer with no issues. Strange...

              diop What version of TeamViewer do you use for the connection? You are referring the same behave as sitting in front of a bad PC for RDP, VNC or both?

                Markus What version of TeamViewer do you use for the connection? You are referring the same behave as sitting in front of a bad PC for RDP, VNC or both?

                Latest version. I mean if I connect to a bad PC from my good PC using TeamViewer, then I don't notice any symptoms. I haven't tried RDP/VNC for ages, they may use different protocols/rendering techniques.

                  8 days later

                  KM Markus diop

                  I tried VNC connecting through android to a Windows 7 and I got an interesting result. If I use the 3.x version of VNCviewer I get eyestrain, but if I use the 2.x version of the same app it doesn't.

                  Also point there is no good/bad computer for me, as all they are bad and have to use only eInk screen, and if it is not enough, some of theme also makes me dizzy.

                  Some time ago I used Teamviewer between a Raspberry pi 3 and an android 4 eReader without anyproblem, and if you are asking it to yourself, eInk can harm depend on the configuration. I have problems with my 13 inches eInk Dasung screen depending on the windows

                  I still use VNC Viewer (from RealVNC) 3.3.1.029981 from 2018. Maybe later versions changed something. That's an impression I had and that's why I didn't update anymore. With Total Commander I keep backups of all my apps so I can rollback at any time.

                    KM The VNCviewer 3.x which causes me eyestrain is the 3.4.3, a later one than yours. Never tried the one you mention

                    Also point I use to use as a Vnc client the Bvnc app, which worked very well

                    5 days later

                    KM
                    Been thinking in a way a little computer like Rasperry or Odroid could be used to have a VNC client which cleans the video signal of the computer we want to use and show it via HDMI to the monitor we use.

                    We can even go farther and do a loop making the computer to be a server and through a localhost loop connect via a client on the same machine, cleaning all the dithering of graphic effects. Honestly, I have no idea how to do that, but its surely doable for some who is linux techy and can spend some hours in front of a computer

                    2 months later

                    I tried to use a device which is bad for me (an android 9 eReader) running a good-known remote desktop client version (NoMachine) and didn't improve the experience. Also tried to use a good-known client version of VNC but didn't worked properly on android 9, so who knows, but probably wouldn't work any way.

                    9 months later

                    KM I have that version on my Android now. Does it matter what version is on the PC?

                    • KM replied to this.

                      degen I don't know. I have used TigerVNC Server for years now on a Linux computer. I can imagine if you used something proprietary/advanced on both ends, it could get worse.

                      On the Android TV I use bVNC as client, which is slower but I think that's actually a good sign as it might indicate missing hardware acceleration. It's the only client I found useful on Android TV as others seem not fully compatible. I have enabled hextile encoding and "full screen bitmap".
                      My server and regular Android client have no special custom settings.

                      I also had faced the same problem but i after using sunglasses in front of a screen the stress become go down. I use to wear Re Aviators Sunglasses in front of a Screen.

                      I have to admit that during the covid lockdown (last year) I worked many times outside with the sunglasses and I felt better, less eye strain than usual.

                      dev