Eye Strain - Temporal Dithering

I don't know for sure but it seems to me that modern video cards don't seem to care how many colors the panel supports. They just dither anyway. Presumably because it's easier to just dither, so that users get wider range of colors regardless if the panel supports 10 bit natively or not. The other reason could be that the more bits for color are transferred the more bandwith it requires but bandwidth has an upper limit and since the brain mixes colors together anyway if you flip them to the eye fast enough, it's more efficient to alternate between two colors than to send the additional bits. I mean, instead of sending a 10-bit color four times like so:

1000100010
1000100010
1000100010
1000100010

you can instead send two alernating colors two times like so:

11110000
11110011
11110000
11110011

(disclaimer: I just made the 0 and 1s up and didn't bother to check which colors they represent but you should get the idea: save 2 bits on every transfer for increasing resolution or frame rate instead).

To the brain the result is the same but to the eyes, for some people, like us, it creates strain.

It could be that in the old days the drivers did the dithering and it could be disabled and enabled from the software but now drivers just send the image to the hardware and the hardware does the dithering which means it can't be turned off because it's "baked into hardware". This seems to be the case with Apple's M-series computers because if earlier there was an option to switch from "Billions of colors" to "Millions of colors" by using Stepane Madrau's SwitchResX then now it just shows "Billions of colors" as the only option: https://ledstrain.org/d/1797-switchresx-developer-m1-mac-does-not-allow-8-bit-color. It could be also that since the GPU in the M-series is relatively new, the driver writers did not bother to expose the color depth option to the OS. Although I'm leaning towards the former rather than the latter.

By the way, I also get eyestrain with modern GPUs. In the case of Macbook Pro 16" 2019, it was literally one minute of use until I felt my eyes hurt. The eyeballs feel like they are burning or like someone is stinging them with needles, especially when I close my eyelids and the pain does not go away many hours after I quit using the device.

I pinpointed my issue with my MBP 16" 2019 with Intel CPU to the temporal dithering by working with a virtual machine. I discovered that the video card the hypervisor is showing to the guest virtual machine is usually pretty basic with 8-bit color depth.

I came to this idea when I was remotely couching an intern and had Teamviewer in full screen mode. I discovered that I could suddenly work whole day on my computer without significant eye strain.

This gave me an idea to try to run a virtual machine on my computer:

I have a Mac but I think it should work the same with a PC laptop with VirtualBox or Fusion or whatever else. They all show a basic video card to the guest OS.

But with MBA 2022 it does not seem to work but instead full brightness lowers the eyestrain on this model for me, whereas with MBP 2019 the brightness did not affect but lowering the color depth with SwitchResX did.

Of course it's more a workaround than a solid solution to our problem but I thought I'd let you know, in case it benefits you.

It looks as if this eyestrain thing is becoming more and more common as people vulnerable to temporal dithering like us are more and more surrounded by devices which employ this technique which is destroying our eyes. I heard eyestrain complains from users already in 2013 but I never experienced it myself until I got Macbook Pro 16" in 2020. Turns out all Macs from 2016 onwards are giving me eyestrain. I didn't just know it yet. If this trend is continuing the way it has, pretty soon we are out of options when it comes to purchasing a new device which does not get us eyestrain. Looks like someone created a petition on Change.org 3 weeks ago about this: https://www.change.org/p/apple-add-accessibility-options-to-reduce-eye-strain-and-support-vision-disability-sufferers.

Thank you for the informative post!

I have been reading on other forums.  It seems there are a growing number of people affected by this.  One person said they had an MRI done on their eyes.  The MRI showed "damage to the frontal cortex consistent with trauma caused by numerous sub-clinical seizures".

https://community.intel.com/t5/Graphics/eye-strain/m-p/535914

I am going to get my own MRI done. 

I signed the change.org petition and will be posting it to other forums.  Any chance you know who wrote that?  Maybe we could amend it to include other vendors and devices, not just Apple, and it would be good to include phones too.  Or maybe it would be good to petition to have this condition officially recognized as a disability.

There are some of us that are worried we won't be able to work in a few years because of this. 

It was written by this guy: https://ledstrain.org/u/lougro

Or maybe it would be good to petition to have this condition officially recognized as a disability.

Where?

I have another question for the Dell folks. 

How does Dell disable temporal dithering with the Intel Iris graphics?

Thank you

 Hi Zodios,
I am just now seeing your post. 

I have looked at 10-bit monitors in stores and they still seem to have dithering.  As hennotaht posted above, dithering seems to be enabled by default now regardless of display panel bit depth. 

I have the same issue. Did Dell respond?

There is Dithering for Intel graphics to disable dither on gpu side. You can google it. But it cannot disable dithering on monitors. Some monitors aren't true 10bit, their 10bit = 8bit + dithering.