KM Did you measure the flicker yet, to see if there's a difference between the lamps?

I am not sure I did things right, and I had to return the equipment so I have not been able to compare "good" and "bad" lamps yet, but here is a preliminary measurement of the flicker of a "bad" fluorescent light.
100 KHz....sounds high to be sensitive to, does not it?

5 months later

On my request, I got the fluorescent bulb closest to my desk changed from 3000 to 5000 K. At the moment of the swap, eyelid twitching was bothering me little and seldom, not sure if my eyes had adjusted a bit to the light or if other co-factors played a role, like diet or slightly better sleep. Note, I still badly suffered from eyestrain and poor concentration / performance.
At the change of the bulb, I found using my MacBook Air and my iMac was a bit more pleasant, however, at the same time I felt my eyes got more fatigued (I know it sounds a contradiction, but that is how I felt). Well, after three days under the new bulb, eyelid twitching returned, and way stronger. The weird thing is that it now affects almost exclusively the right eye, whereas earlier only the left eyelid twitched! At times it is so persistent, that I can not even work. I sometimes have twitching also outside the office, especially when I change my direction of view and when I am talking to people. But it gets really intense when I sit under the bulb. I wish I had some kind of meter to prove that. The onset of the twitching clearly coincided with the change of the bulb, apart from an incubation time of 2-3 days.

I was not expecting much from a change of the color of the light to be honest. I remind you that the same 3000 K bulbs are okay in the neighboring labs, where they run at higher power (I have not tested a 5000 K bulb at high power). So for some reason lower power makes the lamp bad for my eyes, whatever the color temperature.

    AGI Eyelid twitching is a psychological stress reaction.

    • AGI replied to this.

      Does the light make your eyes irritated and then the feeling stays for hours? Happens to me. Happened an hour ago with my backyard lights. Just a few seconds of exposure and my eyes and surrounding face muscles (cheeks) feel like they've been through a marathon, which can persist for hours.

      • AGI replied to this.

        KM Yes, it is similar to when I look at a bad device. Short exposure causes damage, and the damage does not fade quickly upon removing the trigger.
        I do indeed feel enormous tension in my face muscles. I never experienced this before, it had always been more of a neck and back of the head tension, accompanied by eyestrain. In the past though I was always able to dodge bad devices and I was never subjected to such discomforting lighting conditions for long. My twitching did not start immediately. It took about 8-9 months. Initially I only suffered from eyestrain and poor performance at the computer and also reading on paper. You may also remember the story with my Samsung Galaxy on5. I now have doubts that the phone became "bad". It may be that I have subjected myself to unbearable conditions for too long (lighting and two Macs), and at a certain point my body started sending out warnings like twitching and photosensitivity.

        Sunspark Eyelid twitching is a psychological stress reaction.

        I tend to exclude pure psychological effects, if what you mean is that for instance I am stressed out at work and / or do not like my work environment etc. etc. It is not really the case. I am surviving right because I do not have much pressure. But I am unhappy and worried about my state, so that could psychologically influence.
        I am more inclined to think that I have been killing myself for nearly 2 years under horrible conditions, and my body is worn out. I think eye and face muscles are similar to other muscles. If you over-stimulate them and if they are not fit (I do not exclude I have some underlying eye condition like heterophoria), they will let you know sooner or later.

        @KM Have you explored the psychosomatic avenue?

        Partial good news of the last < 24 hours. There has been a rotation of people and a row of LED spotlights which we used to keep off has now been turned on by the newcomer. I freaked out but interestingly working at the desk feels a bit more pleasant. I hope I can confirm. And if it is the case I will try to run some tests and dig out light specs.

        • KM replied to this.
        • KM likes this.

          AGI Have you explored the psychosomatic avenue?

          No, not yet. I still refuse to believe in this. The symptoms are 100% reproducible, with different results for different lights. There must be a medical explanation other than "it's all in your head". Plus I suffer from PWM, driver eye strain, pretty much all the main problems that have been discussed here. So we all have similar symptoms and the reason for that cannot possibly be we all had the very same psychosomatic problem. Makes no sense, doesn't seem likely at all.

          From my perspective it seems there is a disagreement of our brain to the displays / light we look at. The stimulus (light/display) creates a specific response which may be similar to the stress response, but it is the device or light that creates this.
          After some years of training in somatics i can quickly reverse any of the symptoms i get from any device, however this cannot be a permanent solution to engage every 20 mins in 10 mins of release activities to reduce the tension in my body.
          So for me this is definitely a tech issue and there is a very clear and distinct stimulus. The new displays/lights create all kinds of tensions in the head and upper body starting with the eyes. Also the eyes initiate and control most motor behavior so it is normal for tension to appear in various forms in the head and upper body (eg headaches, neck/jaw, etc).

            Peter After some years of training in somatics i can quickly reverse any of the symptoms i get from any device

            Interesting. I know nothing of somatics. Is it some kind of exercise involving controlled breathing?
            Do you suffer from instantaneous severe symptoms in front of "bad" devices?
            Do you mean that, if you did not have to use the bad device anymore, after practicing some exercises for a few minutes you would be fine and free from symptoms for the rest of the day?

              AGI Somatics is the genre for some body training methods like the Alexander Technique, Feldenkrais, Pilates, etc. Personally I am studying the Alexander Technique for about 5 years due to a back problem.

              I can actually get back to almost symptoms-free in less than 30 mins. After two or three hours i am like i never used the bad device. And yes i do get instantaneous severe symptoms if i use a bad device.
              However learning any somatics techniques takes time.

              My Alexander teacher believes that if my eyes become more flexible in their movement i will be able to adapt. We are working specifically on this for a couple of months now, however i still cant say i have seen significant progress but i know it takes time to alter long standing muscular habits.

              • AGI replied to this.
              • AGI likes this.

                Peter i know it takes time to alter long standing muscular habits.

                Thanks for sharing.
                So it has to do with muscles. It is not a psychological issue, at least in the first place. That was my thought too, without being an expert in the field.

                3 months later

                Seagull Probably comes down to how they are powered. If the LEDs are powered by a standard light bulb fitting that will take any type of bulb they will flicker. But, if they are driven by some purpose built LED power supply, with a proper AC-DC rectifier, they will not flicker.

                Moved from My treatment progress and search for solutions

                Interesting! Would that apply to fluorescent bulbs as well? Summarizing the thread I had opened and forgetting for a moment about the LEDs, I got rooms with fluorescent bulbs run at low power which drive me insane and other rooms where the same model of bulbs are run at higher power and give me no issues. I was changed the bulb color temperature in the office but the power could not be varied, and I still have fatigue and eyestrain / eye twitching. So it does not seem to be color temperature related.

                  AGI

                  I don't know, I'm not familiar with fluorescent bulbs. Perhaps your lower power fluorescents have less persistence, for some reason.

                  I also don't know if any overhead light is installed with proper ACDC power bricks - but if your light fitting was something elaborate that might be the only way to do it. The reason normal household LEDs don't have proper AC-DC rectification comes down to space, then weight, then cost. But if you are installing something fancy, with the wiring hidden in the ceiling, decent rectification, and hence no flicker LEDs is achievable.

                  • AGI replied to this.

                    Seagull if you are installing something fancy, with the wiring hidden in the ceiling, decent rectification

                    This is the case. The building is ~ 4 years old and was designed to use modern lighting.

                    Seagull no flicker LEDs is achievable.

                    What do you mean with no flicker? High enough to not be perceived? Do you have a figure of the magnitude?

                    So you do not have problems with LED lighting, do you? Only with displays?

                      AGI

                      If you power an LED with DC there will be zero flicker.

                      I can't use computer displays when the room is lit with household LED bulbs without discomfort. I'm fine with flourescents.

                        a month later

                        Seagull
                        I am totally the opposite. My eye get irritated from looking to the computer monitor if there is fluorescent light within meters. Now i replaced them with warm flicker free led and things going smooth.

                        I'm glad this is a current conversation. I started using a Xiaomi flicker free led desk lamp today, presumably using some form of dimming. The thing somehow gives me friggen migraines and nausea after minutes! I was so sure that a constant light source would be fine but it must be something to do with LED spectra as well. Funny thing is, the LED spectras i've seen online all look pretty smooth. Keen to see what you guys come up with over lighting.

                          Seanicus

                          I bet its not really flicker free, does it have a hefty laptop size power brick?

                          Have you seen the soundcard oscilloscope thread? the simplest photo diode iterations shown in that thread should be sufficient to test it. From my experience, testing lights for flicker is a lot easier than screens owing to the high lumen output.

                          a year later

                          What do people recommend as the safest bulbs/overhead lighting?

                            Quad43

                            Incandescent. 100%. It is true black body radiation, same as sunlight.

                            You can still buy incandescent bulbs, the ban was very limited to specifically standard service A19 bulbs. You can buy incandescent flood lights, B19 bulbs, A19 rough service bulbs, chandelier bulbs, etc.

                              dev