Nice. What I meant was more along the lines of ... there used to be an app that let us tell the machine to ONLY use nVidia, that doesn't work under newer versions of OSX. So we'll have to figure out a way to not have it switch back to Intel.

  • JTL replied to this.

    All I'm willing to say at this time publicly is that some major technical hurdles have been overcome, with regards to the framework needed for injecting the code for disabling the dithering in the AMD/Nvidia kexts under OS X, but it's not done yet.

    diop Will Intel be a possibility in the future? Or could the ditherig tool be ported over to OS X?

    If someone makes a Linux version of the dithering tool, it might be possible for it to work under OS X. Again, not making any promises here.

    5 months later

    Looks like a UK Apple Service Provider either re-sell or are involved with AHK as I discovered this post.

    Link: https://www.jigsaw24.com/news/amulet-hotkey-fix-temporal-dithering-for-latest-macos

    "If you're using Amulet Hotkey for KVM over IP, be warned that installing the latest version of macOS on your endpoints automatically re-enables temporal dithering.

    This vastly increases the amount of information you're forced to handle over IP and, as a result, will have a negative impact on the quality of your image.

    Happily, Amulet Hotkey are already aware of the issue, and have released a kernel extension that allows you to disable temporal dithering at the driver level, regardless of which version of macOS you're running. (If you're running an earlier version of macOS or OS X, the fix should already be in place – contact us if you find this isn't the case.)

    The usual caveats apply: the fix will only work with Amulet hardware and software, not with that from third parties; the kext itself is not available publicly – in a delightfully cloak-and-dagger scenario, you need to get in touch with our team on the details below, and they'll send you a temporary download link and instructions for how to install it."

      diop "The fix will only work with with Amulet hardware and software" 🙁

      • JTL replied to this.

        ryans It only works "with Amulet hardware" because there is code to check if the Amulet box is plugged in or not. It was a delibrate design decision to lock out competition.

          JTL True, in Amulet's case, the dithering is a nightmare because static images never exist. I think Apple should allow us to turn off dithering.

          I'm hoping at some point we can disassemble or hack Amulet's driver. I think it's pretty frustrating that a solution exists but we can't use it!

            Gurm I agree it's frustrating. We should petition Apple to allow us to do this...if we can't get through via support, maybe we can find engineers at Apple on LinkedIn or similar and try to make them aware of this issue. Most people are under the impression that dithering is not perceptible by humans, but as we know, it can still have an adverse affect on us.

            I don't use OS X and I don't know much about Kexts, so one possibility could be to use Rent-A-Coder or something like that, and maybe pay someone that has the experience to make one for us (and make sure we get the source code). I'd be happy to chip in for this for our community. As JTL mentioned in another thread, disabling dithering is a competitive advantage for the Amulet folks, unrelated to eye strain.

            The fact that it can be done on OS X is very encouraging. I don't know if iOS is known to dither, but it's very locked down, and I strongly suspect it's not possible to disable or alter without jailbreaking.

            • JTL replied to this.

              ryans I've been working on this for 6 months and have made very good progress. No need for any "Rent-a-Coder" or similar.

              Email me and I'll give you a "brain dump" of all my research so far.

                ryans Doubt it, the issue is the graphics driver, not the actual GPU itself (with exception of possibly GTX 9/10xx)

                JTL I'd love to release an open source program that disabled dithering on OSX just to spite Amulet Hotkey. They know we are suffering and just don't care.

                  JTL are you implying that you found a way to disable the temporal and spatial dithering in macOS?

                  What is a good way to test eyestrain caused by macbook dithering ? Is the recovery mode option still viable with he latest macos and intel integrated gpu?

                  • JTL replied to this.

                    Seefree are you implying that you found a way to disable the temporal and spatial dithering in macOS?

                    Getting very close. I found a way to make it worse, now to make it better 🙂

                    What is a good way to test eyestrain caused by macbook dithering ? Is the recovery mode option still viable with he latest macos and intel integrated gpu?

                    Unsure

                      5 days later

                      ryans I saw that, your point?

                      I have the 2015 15" MBP with dedicated graphics, which running Linux always uses the AMD GPU unless using special EFI hacks.

                      I haven't tried it with Linux in quite a while but Ubuntu 16.04 (I think that was it) was fine.

                      I wonder if a high speed camera (like 1000FPS) that took a video of a laptop or smartphone that caused issues, and we slowed it down, we'd be able to detect dithering or other sources of flicker?

                      One of the biggest problems we have on here right now is there's no reliable test for anything but PWM (using a smartphone camera, but even that is not 100%)

                        ryans With regards to PWM, get a high quality oscilloscope and photodiode. Both can be purchased for <$1000. Have a look at @TechSensitive's posts.

                        With regards to dithering. I want to try a lossless PCIe capture card to check several display outputs in slow motion. Can be purchased for ~$400 at most on eBay.

                        There's a company in Vancouver that makes a high speed camera that does up to 21,000 fps. It costs $3000 but I know someone who works there and I might be able to test one at their offices.

                        http://www.krontech.ca/

                          dev