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iPhone 17 Models Include Toggle to Disable Screen Flickering (PWM)
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My OLED TV only dips in brightness for about 0.15% of the the refresh time. The dip on my Pixel 8 Pro at full brightness is about 12.5% of the total refresh time (it has very similar PWM characteristics to an iPhone, from what I've seen).
Yep, so if 0 is the lowest screen brightness, and 10 is the highest, and the modulation is 100% that means that 480 times a second the screen is going from 0-10 on the brightness scale, increasing the 'strobe' like effect. A lower modulation (even with the same low flicker rate) is better on the eyes as the difference between the min and max brightness on every flicker cycle is less.
50% is still VERY high (Good OLEDs are already down below 10% like the Honor 200 Pro) so this isn't going to be much use to sensitive folk based on those numbers alone (if accurate of course)
I think the testing methodology is broken. Almost all screens, including OLED, refresh from top to bottom (or a rotated version of that). The whole screen does not strobe at the same time.
I think what's happening here is that the light sensor covers an area, so it's reading some pixels that are 100% lit up, and others that are 0% lit up, and essentially taking an average.
Basically, the screens have narrow bands of pure black, but the testing sensor is mistaking them for slightly wider bands of less depth.
So it doesn't disable PWM and it looks like the 17s are still a no go for a lot of us.
I can only hope the attention that's been drawn to the issue will have helped some people who weren't aware, and shown Apple that there is demand for a real solution. Also, Apple at least acknowledging it as a genuine accessibility issue for some people is still massive.
Hold out iPhone 11...
I can only hope the attention that's been drawn to the issue will have helped some people who weren't aware, and shown Apple that there is demand for a real solution. Also, Apple at least acknowledging it as a genuine accessibility issue for some people is still massive.
Hold out iPhone 11...
Problem is for many of us the iPhone 11 doesn't work anymore since Apple insist on using loads of temporal dithering since iOS18 onwards... mine runs on iOS17 and it's 100% comfortable, my 'test' iPhone 11 is BAD on iOS26.
I did the mistake to update my 11 and i have headaches for f shake. How many days do I have to decide if to downgrade ?
I've actually been using my 11 more and more via iPhone mirroring these days for more comfort, I'm not sure if it's a result of iOS18 or just my general migraine/eye strain woes. So I'm definitely going to be cautious about any upgrade to iOS26.
Welp, tried it on the Air at home and didn’t do anything for me. Within 5 min the pressure was already building up in my head and went back to my 16 Plus which is still barely tolerable.
PWM setting is definitely doing it’s job in low brightness (30% and below) so the presumably insane modulation on the Air is most likely the culprit. The Pro arrives tomorrow but those have routinely been the worst for years so not looking good.
PWM setting is definitely doing it’s job in low brightness (30% and below) so the presumably insane modulation on the Air is most likely the culprit. The Pro arrives tomorrow but those have routinely been the worst for years so not looking good.
This is the trend with LCD iPhones, iPads, and Macs: they’re utilizing even more dithering to render the 10-bit MacOS/iOS/iPadOS graphics. OLED iPhones (likely because they are somewhat closer to 10-bit) don’t engage it as often, but it’s still there. This is why I’m still on iOS 15 on my iPhone 13.
iOS 26 and the whole “Liquid Glass” design made me immediately assume they’d utilize dithering for all those gradients. What a mess.
My phone just arrived, hoping setting the toggle feature on and reducing the refresh rate helps…as a tech enthusiast it sucks not being able to use a modern phone.
This makes a lot of sense. My M1 Air became unusable from Sequoia onwards, presumably dithering, had to sell it.
Apple is forcing me out of it's ecosystem.
I'm going to try the 17PM for a short time today under 30% only with the toggle on, I will say it IS an improvement, but it's nowhere near enough for me sadly, and to only work under 30% brightness is a no-go on a phone this expensive.
If you're sensitive, turn the setting on! (Sadly it is not that promising so far and needs more tuning or a complete overhaul)
Tools like Better Display can turn off dithering. It has made my M1 Air comfortable to use again. Could barely use it with an external display prior to this.
Still on ip8 and was thinking about upgrading to a 13 mini or something, thankfully this topic reminded me of the PWM issues, maybe it will have to be an XR or 3rd gen SE for now (but then of course the withering, is that an issue on SE's?).
While I am not sure if I am sensitive I do not want ot take a chance as I suspect I might be, see next reply:
I wasn't expecting to read this post but word for word dude!
I too would point this out to people, but wasn't it 75Hz?
60/75Hz iirc was what most CRT could handle and was in settings, and oh to stand aloft, in an open plan office looking out over a sea of flickering screens.
No one ever noticed. Except me.
We are a rare breed I guess. Maybe the type less prone to being hypnotised! 😅
I found the further you stood away the more noticeable it would become and if you hummed (which might activate it in others) or placed a plastic rule in your mouth gripped in your teeth and twang'd it (can't think of another word) the vibration or hum would induce a vibrational wobble would make the screens go crazy
So whatever way perception works, the brian obviously has an algorithm as such to cancel out vibrational interference but with the skull vibration becomes over-whelming or contra-sync maybe with the frequency of the screens clicker it can't out-process the flicker/interference in these cases. That's how to induce it if you an't see it methinks, 'course not a lot of CRT around anymore and I am not sure how it works with triple digit Hz rates.
I wonder do you have sensitivity to audible High Frequencies too?
TV/CRT's would make some whine when turned on initially.
One step at a time maybe to see how it is received and then Apple can gather/track feedback on the implementation, or is it a seen to be doing something quasi legal protection (fudge).
I remember finding florescent bulbs kinda mesmerizing to look at because you could see the light kinda pulsating like a plasma almost like a lava lamp.
And yea I think 75hz was still noticeable. I recall setting mine to 100hz and I could still see a very faint change in brightness across the scan.
And the high pitched whine always drove me nuts!!!!
Also a lot of 2000s-2010s laptops had CPUs that would buzz/sizzle depending on their power management modes.
Whatever it is, coil whine or other things, power outages can be kinda spooky serene because of how quiet everything is. But then I notice my tinnitus more lol.
Oh yea totaly forgot about fluorescents they would kill me. Maybe these were older tubs?
IIRC they would be rather wide tubes compared to most common T8's, perhaps giving the gas more space to move/be seen.
You could walk into shops/stores. Suddenly your eyes get a bit blurry looking at menu or signs, perhaps bleary is the better term.
In the workplace, which I had control of, I eventually found and installed tri-phosphor tubes. So that's 3 phosphors mixed to get a wider spectrum of light in the I think 90 or 95 colour range, amazing how much more colour range you could see(LED wer not on the market). The reds and blues differentiated better, absolutely closer to fuller spectrum and the headaches stopped! (typically units shipped with 65's which is as good as being in the dark ffs)
The move to new LED streets lighting is simply horrific. Halogen street lights were far superior, possibly the best light of all streetlighitng to date, if that's what they were. There is no other way to describe it.
Even though old orange sodium lamps would make me a bit sick as s kid, now when you still find some, you can relaly notice how much more you can actually see at night time compared all others but especially the LEDs, the LEDS make everything darker (cause it's in the daylight range of the spectrum), and only the light is the bright thing.
So you see far less at night. Exactly what you are trying to solve. Nightvision is not engaged correctly. Well I don't want to derail the topic but clearly the pace of technological change is playing havoc with our biological senses in more ways than one primarily in the area of LIGHT!
In the last 5 years all our artificial light sources are now in the main LEDs, computers, phones, streetlight, car headlamps, home lighting. This is a BIG deal. I certainly think my eye sight is less tolerant, while it could be age and it can happen near vision with phones is not great anymore. I can not help but think this transition to LED as the primary light source everywhere has had some less that positives effect.
That's it, I'm done. Sold my Macbook Air, iPhone 11, all 4 Airtags, Apple watch and Airpods Pro 2. No choice.
Now using an IPS Android phone which is perfectly comfortable, if a little mid-range.
I applaud Apple for making moves in the right direction, but they need to go faster and sort out the horrendous dithering too. My previously perfectly comfortable iPhone 11 had become a torture machine.