I am not sure if I would notice if a pixel count changed by a factor of 1.2, but when you double the resolution (4x the pixels) the difference is dramatic. The screens on my iPad2 and iPad4 are very different, and while I didn't mind it when it was new, the iPad2 now has painfully low resolution.
> he screens on my iPad2 and iPad4 are very different, and while I didn't mind it when it was new, the iPad2 now has painfully low resolution.
Absolutely! But that's going from 132 PPI to 264 PPI.
Obviously there's diminishing returns at play here. The difference between 1000 million PPI and 2000 PPI, I'd wager, isn't going to make an actual impact on someone's viewing experience.
And I really wonder if a change from 350 up to near 500 would. Surely there's a change, but I'd say a minor one, and given you're pushing way more pixels, the cost to battery / hardware might not be so trivial.
If anyone can substantiate this last point with some numbers, I'd be very curious to hear.
To some degree it depends on your vision. The 264 PPI is about my resolution limit. My boss probably couldn't tell the difference with more than 100PPI.
I should be able to tell you the theoretical diffraction limit based on a 5mm pupil at 18", but unfortunately...
