• redwattlebird @lemmings.world
    link
    fedilink
    arrow-up
    9
    ·
    21 hours ago

    Wait, I’m a specialist lighting designer and i haven’t heard about this < 100hz LED is bad stuff. From my experience, frequencies at around 50hz or lower is what usually causes eye strain/headaches etc.LEDs are typically 60hz.

    I’m guessing the >100hz crowd just need to go outside and touch grass for a few hours a day.

    • chonglibloodsport@lemmy.world
      link
      fedilink
      arrow-up
      13
      ·
      21 hours ago

      50Hz is what you’ll find in the UK and Europe.

      LEDs aren’t 50Hz or 60Hz or anything else. They’re DC devices and they don’t flicker at all if you run them on a clean DC power supply.

      The issue with LED bulbs is that they don’t have clean power supplies. They have very simple AC to DC, usually a capacitive dropper. Without filtering, this type of cheap power supply produces a lot of ripple which manifests in visible flicker at the same frequency of the input AC mains power.

      • ChaoticNeutralCzech@feddit.org
        link
        fedilink
        English
        arrow-up
        5
        ·
        edit-2
        20 hours ago

        Yup. Except they flicker at double the mains frequency because they use both the positive and negative half-cycle thanks to a FULL BRIDGE RECTIFIER.

        And see my other comment: it’s not unhealthy, just annoying. To be honest, I use trash-picked LED bulbs and repair them, and I don’t normally care to replace a poor smoothing capacitor. In rooms I spend much of my time, I make sure most bulbs in the fixture are low-flicker (it’s arbitrary but generally don’t get below 75%) for comfort. I’m not peculiar about light quality like CRI and matching color temperature unless it’s very obviously bad, although I do notice the circadian effects of cold white light. I do mark badly flickering bulbs though so I know not to put too many of them together unless it’s somewhere non-consequential like a cellar. I also hold my phone camera to any neutral-white E27s I salvage to find and mark true flicker-free ones because I use them while filming.

      • redwattlebird @lemmings.world
        link
        fedilink
        arrow-up
        3
        ·
        21 hours ago

        That just means the driver is not flicker free, not the LED board itself, and there are flicker free drivers out there but they’re just not available for the average consumer.

        But visible flicker? On an LED that’s just emitting light? I’ve never seen that before. Maybe it’s a UK and Europe thing.

        • chonglibloodsport@lemmy.world
          link
          fedilink
          arrow-up
          4
          ·
          21 hours ago

          I live in Canada (60Hz here) and I just installed a new range hood above my stove. It came with standard recessed halogen light fixtures with LED bulbs. Rather than being fully dimmable, the switch has high and low settings. When set to low, I can definitely see visible flicker.

          I also have this same style of lights above my bathroom mirror and a dimmer switch there. They also display more and more flicker when dimmed.

          • redwattlebird @lemmings.world
            link
            fedilink
            arrow-up
            1
            ·
            18 hours ago

            Ah. That’s a driver issue again. The dimmer is adjusting the voltage, and it the voltage dips too low, the LED chips don’t have enough juice to run. Hence the flickering. If there is a driver attached to your LEDs, you might want to consider a 0-10V driver or one that specifically says flicker free.

            EldoLED drivers are excellent for this but costly because they’re commercial grade.

              • redwattlebird @lemmings.world
                link
                fedilink
                arrow-up
                1
                ·
                18 hours ago

                Ah connected to mains. There would be a way to add a driver in between but will require an electrician and it’s just not worth it if you can just put it to high output.

                • chonglibloodsport@lemmy.world
                  link
                  fedilink
                  arrow-up
                  3
                  ·
                  17 hours ago

                  Electrician? I do my own electrical work! This issue is pretty low priority for me though. I have a ton of other things to fix around the house!

    • ChaoticNeutralCzech@feddit.org
      link
      fedilink
      English
      arrow-up
      5
      ·
      edit-2
      11 hours ago

      Poorly made LEDs actually flicker at 120Hz on 60Hz mains, see my other comment. And it’s more like a pet peeve, only below 60 Hz is actually headache-inducing. Unless it’s specific circumstances (I couldn’t stand a cheap 120Hz PWM RGB strip close to a gaming monitor because I’d see annoying “rainbows” as my eyes dash across the screen). More details in my other comments.

      • redwattlebird @lemmings.world
        link
        fedilink
        arrow-up
        4
        ·
        18 hours ago

        Very interesting! My pet peeve is glare and LEDS produce an ungodly amount of glare and I absolutely hated them in car headlights. I’ve never heard of anyone irritated by hz that high before. The more you know. Thanks for clarifying.

        • ChaoticNeutralCzech@feddit.org
          link
          fedilink
          English
          arrow-up
          2
          ·
          11 hours ago

          Glare? That’s not a physical property of LED light but an effect of overly bright headlights enabled by LED and laser technology.