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    I don't know what forum to put this. Why does F.lux not filter out ALL blue light?

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    • TwoCablesT
      TwoCables
      last edited by TwoCables

      Another thing to consider is the brightness of light. Even with pure red light, dimmer is better.

      Also, there is indeed blue light bleeding from a monitor. I see it when I have a white object near the base of my monitor (in front of my monitor) or a shiny silver reflective object in that spot. Even with 1200K or Darkroom Mode, I still see the blue light reflecting off of the white or silvery-reflective object.

      Try it: in a very dark room with f.lux set to 1200K, put something very white right in front of your monitor at its base. You might notice the blue standing out against all the red coming straight at you. Its like blue is being beamed up and down from the monitor, but not straight out at your eyes. It can almost appear as though the bottom is still emitting 6500K at a downward angle (and at an upward angle).

      Tungsten_smoothT 1 Reply Last reply Reply Quote 0
      • Tungsten_smoothT
        Tungsten_smooth @TwoCables
        last edited by

        @TwoCables If the OLED people can fix the PWM backlighting, then it will solve this problem completely!

        TwoCablesT 1 Reply Last reply Reply Quote 0
        • TwoCablesT
          TwoCables @Tungsten_smooth
          last edited by

          @timpster said:

          @TwoCables If the OLED people can fix the PWM backlighting, then it will solve this problem completely!

          The market does have flicker-free LED monitors.

          Tungsten_smoothT 1 Reply Last reply Reply Quote 0
          • Tungsten_smoothT
            Tungsten_smooth @TwoCables
            last edited by Tungsten_smooth

            @TwoCables Yeah, but I'm talking about "organic" LED, OLED, which currently has a PWM diagonal flicker that I can see very well. It's terrible!

            In fact, if you look up on youtube, Samsung Note 4 auto brightness outside, you'll see the flicker on camera. For me it's not black lines, it's like... a fuzziness constantly screwing up my reading, video watching etc, it's just awful.

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            • TwoCablesT
              TwoCables
              last edited by

              Everything has flicker though. All of your light bulbs, your monitor, etc.

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              • lornaL
                lorna
                last edited by

                If you're flicker sensitive it's dreadful because the thresholds for some consumer applications are too low. I haven't been scientific about figuring this out, but I can see over 200 fps. If the PWM is a square wave it makes me feel physically ill. Elevator retrofits are often the worst offenders for some reason. And there's one restaurant nearby that I can't go into after dark because they retrofitted their LEDs with square wave PWM. It is like trying to walk through a strobe light for me, and everyone else is just eating their noodles, NBD. https://en.wikipedia.org/wiki/Flicker_fusion_threshold

                @lorna

                Tungsten_smoothT 1 Reply Last reply Reply Quote 1
                • Tungsten_smoothT
                  Tungsten_smooth @lorna
                  last edited by Tungsten_smooth

                  @lorna Yeah, I can clearly see my phone flicker in my mirror from.... 7 -9 feet away at night, like how the hell did they let that pass? And then if you run dimmer apps, it's just stupid visible. Why haven't they gotten it right!!

                  Also I can see the flicker on stock low brightness from 10 inches away, which puts a shimmer on the text and prevents me from reading it. It's exactly as bad (or maybe worse) than PWM on normal LED, not sure yet, but it's down right awful.

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                  • lornaL
                    lorna
                    last edited by

                    @timpster People are looking into it, so I'm hopeful. We're what they call "flicker sensitive people" hah. Lots of goodies in here: http://energy.gov/sites/prod/files/2015/11/f27/miller_gaines_flicker_portland2015.pdf

                    @lorna

                    A 1 Reply Last reply Reply Quote 1
                    • A
                      arioda
                      last edited by arioda

                      Last visit at LightFair I was aghast that most LED driver modules operate with significant 120Hz flicker as do Seoul Semiconductors Acrich 120vac straight off the line modules and they don't seem to care! Yikes. The min flicker frequency for our lamp is 2KHz at minimum brightness <1% and at full brightness is in the 10's or 100's of kHz. Next time you are at Home Depot or anywhere there is an LED rapidly wave your hand in front of it and look for stroboscopic effect. This is a good way to detect flicker. I just checked out my iPhone that way and now I will have to try with a 'scope and a photocell. Thanks for giving me another reason to dislike my phone :(

                      Tungsten_smoothT 1 Reply Last reply Reply Quote 0
                      • A
                        arioda @lorna
                        last edited by

                        @lorna Great slide deck. Filed it in two different libraries :) Thanks!

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                        • Tungsten_smoothT
                          Tungsten_smooth @arioda
                          last edited by

                          @arioda said:

                          Last visit at LightFair I was aghast that most LED driver modules operate with significant 120Hz flicker as do Seoul Semiconductors Acrich 120vac straight off the line modules and they don't seem to care! Yikes. The min flicker frequency for our lamp is 2KHz at minimum brightness <1% and at full brightness is in the 10's or 100's of kHz. Next time you are at Home Depot or anywhere there is an LED rapidly wave your hand in front of it and look for stroboscopic effect. This is a good way to detect flicker. I just checked out my iPhone that way and now I will have to try with a 'scope and a photocell. Thanks for giving me another reason to dislike my phone :(

                          I've never seen flicker on an LED lit screen, well, again unless it uses PWM, but I've not seen it on phones, until every damn android phone went to OLED, then I see it way too much.

                          Anyway, that part about having very high frequency on the LEDs, I can't thank you enough. I didn't get a couple on the kickstarter, as it was decided that we'll wait until it's fully ready, just so there's no issues and such. So I'll get one next year, I'd have to wait a bit anyway so I don't mind if it cost more, I'll support you!

                          Also back to the LEDs at the store, I don't have to wave my hand, I can look straight at it and see it. It's ridiculous--can they just hire me and let me fire anyone who says that 120hz is O.K.? I really just want to fire all of them! Also whoever wrote the spec on it, REALLY wanted to push it up to 150hz, but guess how that worked out.

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                          • Nick CheungN
                            Nick Cheung
                            last edited by

                            This post is deleted!
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