I tested a 2015 15” MacBook Pro Intel graphics laptop on MacOS Catalina recording under Carson Microflip microscope with an iPhone 240 fps slow motion footage. Below you can find 3 videos. The first two are on the “New tab” gray gradient in Safari. The third is of the light gray wallpaper in the Apple settings.
Safari gradient #1
Safari gradient #2
Light gray wallpaper
My analysis:
- Blue pixels are consistently chipped. I received this laptop for free and it isn’t in great condition. No idea what caused this
- Gray dithering very apparent. Looks identical to the iPhone 5 dithering on gray
- I noticed “lightning strike” style flashes on portions of the video on gray. I have to go back and do a new edit to see if I can catch it. Not sure what that could be. It was visible to my eyes while recording (transistor leakage?)
- On Safari new tab page certain colors are pulsating, or appear to be to my eyes. This is similar to what I saw on the 13” M2. My working theory is this is FRC or another type of panel driven dithering, and requires 960 fps slow motion to detect it more clearly
- I believe the dithering on the gray wallpaper is GPU based, but again this is just an assumption based on iPhone 5 comparison. Someone would have to test the iPhone 5 on earlier software (not iOS 9) to determine whether this is panel based or was rolled out via an iOS update, and therefore conceivably GPU based
- Or the gray dithering is panel based and connected to the gray color flicker. This is hard to isolate without better tools and a flicker free Mac screen, which does not seem to exist
Overall I’m quite pleased with this very basic testing. It confirms that dithering is indeed occurring on this device and matches symptoms I have personally had, and I know symptoms many of you also had on this once believed “safe” device.