JRUK
I disabled Font Smoothing on both the 13” and the 15”. The 15” actually caused what my doctor said was a “focal aware seizure” based on symptoms I had: left eye shutting, tingling feeling down my face, tachycardia, sweating, and myoclonic spasms. Full disclosure, I do have underlying chronic health problems (long COVID, POTS) but I have not been diagnosed with epilepsy as of now. I have a follow up appointment this summer.
Things I tried:
- Turned off Font Smoothing
- Stillcolor & BetterDisplay
- Reduce Motion and Reduce Transparency
- Auto Brightness Disabled
- Location Services and BlueTooth disabled
- Messed with contrast within Settings and BetterDisplay
- Entered Safe Mode
- sRGB and other color profiles
- Various brightness levels
All I can say is that the 13” was more tolerable than the 15”. I barely made it through setup on the 15”. And it’s not font smoothing that ultimately caused my seizure: it’s a low frequency flicker. I had to get my mom to erase the computer before returning it to Apple and I had to look at the screen from an angle and I still started to get the same symptoms within seconds. This was 4 days after I had last used it. It was less intense because Stillcolor was enabled but had I used it for longer, I guarantee the same thing would have happened.
The only other time I’ve ever gotten symptoms similar to this has been being in LED and fluorescent lighting with a very low flicker frequency. I was in a Best Buy the other month and I almost passed out because the entire store has LED lights dimmed and outputting a low frequency flicker. Last summer I was in Target where they had somewhat older fluorescent lights, and since it was 15 minutes before closing, they dimmed the fluorescents while I was walking to checkout and I literally had to leave my items and exit the store.
I’ve posted another thread on here with videos and I’m pretty sure this is my particular issue. My guess it’s dithering that interacts with the 60Hz refresh rate on the LCD models, as it’s much worse on gray colors, which would put it well within the danger range for causing seizures in sensitive folks. I have a 15” MBP 2015 that has this issue, too, but it isn’t nearly as aggressive as the MBA M4 models.
So yeah, I think this is why many of us find no relief with IPS LCD MBA’s running Stillcolor. Dithering is being applied by a different component within MacOS and the hardware and it’s interacting with the backlight in a dangerous way. It could be some weird battery saving PWM, too, given how I’ve seen it across different Macs going back a decade.