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Comment by BigJono | Hacker News Reader

This seems like a bug. I've been using f.lux for years across multiple home and work computers and never had a problem with YouTube videos.

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It happens when you play full-screen videos on a mac. The full screen mode displays in a more direct screen access manner (but only after any overlays, like video controls, have faded out). In this mode, f.lux's color profile changes can cause weird blooming issues, especially in bright ares of the video (like a blue sky). Apple seems to have built their solution in a way that avoids this issue.

It's likely f.lux cannot ever do anything about it. Until Night Shift was available, I've been in the habit of of creating "low color temp" color profiles and manually setting my display to them when it gets late in the day (a crude approximation of f.lux, but ultimately the same thing they are doing). It always produced the same artifact.

Incidentally, I find it strange that f.lux is claiming they output so much less blue light than Apple's Night Shift, since as far as I can tell, all they do is shift the color profile, just like Night Shift does. Anyone who has seen the video issues I'm describing above can attest that there is still plenty of blue light coming out of the screen with f.lux (and manual color profile adjustments). All three accomplish the same thing, it's just that Apple's implementation appears to be cleaner and work in more cases (not surprising -- it's their system, so presumably they know how to integrate with it better than anyone). I think perhaps at most they have a point that the default settings are maybe not "warm" enough, but that's the only flaw I can see.

I have artifact issues with f.lux whenever I'm watching videos in full screen mode. It seems that anything "white" coloured becomes fluorescent. Making the nav / time bar pop up with my mouse seems to make this all disappear. This is on a 2014 MacBook Air running the 2nd latest version of OS X.

Interesting. Is it a subtle effect? Maybe I just haven't noticed it before.

Not really. These artifacts are very bright white coloured. It's almost as if F.lux can't deal with certain shades of white and forgets them.

F.lux doesn't "deal" with anything, it just takes your existing ICC/ICM file, alters it, and resets your GPU's LUT with it.

I've had the same issue with an Intel GPU'ed MBPR 13" (ie, no Radeon or Nvidia GPU also), and it rarely happened in OSX, but only during certain HW accelerated overlays (such as YUV acceleration in videos, or OpenGL programs doing sufficiently interesting things).

I don't think F.lux has the bug, but OSX's rendering pipeline does. I had similar issues with color profiles I generated myself that noticeably differed from the screen itself (Apple has yet to produce an actually fucking accurate-to-sRGB screen, I don't care how many Photoshop jockeys praise their lord and savior, St. Jobs).

So, yeah. In other news, my MBPr runs Windows 10 and I'm never going back; and I've also never seen the bug here.

The side effect is: F.lux's Windows version is not feature complete with OSX's, and noticeably redshifts at different times than OSX does depending on what settings you prefer.

It's not very subtle. I just whipped together an example[1]. Note that I had to take a photo of the screen with my phone to show what the screen is actually displaying.

[1] http://imgur.com/a/2amF8

I have had the same bug for about a year.

I don't entirely understand the reasons for it, but if you have a MacBook Pro that can switch between integrated graphics and discrete graphics, disabling Automatic Graphics Switching under Energy Saver will fix the problem.

Yep, the issue only seems to happen on the intel graphics card. I believe it's a driver problem.

It occurs on machines with Intel integrated video only in my experience. Does it on my 2011 MBA and 2016 touchbarMBP, but not my 2012 rMBP. It's well documented here:

https://forum.justgetflux.com/topic/58/strange-colors-blue-f...

I always use gfxcard status to force machines into integrated only mode and I've still never encountered that issue.

Perhaps because it is related with the automated switching which you disable in this way?

(Also if you have an external display connected, "integrated only mode" is ignored in gfx).

F.lux team claims that's an Apple bug. If it's true, Apple doesn't have reasons to fix it.

I've got the same problem. It disappears if any UI element other than the video is visible; this includes even UI elements inside the video itself.

But I usually just leave my mouse over the Mac menu bar.

I have constant artifacts with flux enabled and youtube videos.

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