The math in this article doesn't seem to add up correctly, as far as I can tell. Its calculation of the Vision Pro's PPD (pixels per degree of vision) seems way too high.

The Vision Pro has 23 million pixels total, or 11.5 million per eye, or 3,391 x 3,391 if square.

The Quest 2, by comparison, is 1,920 x 1,832 per eye, or 7 million pixels total across both.

So the Vision Pro has 3 times the total pixels of the Quest 2, but just 1.81 times the number of pixels along a single dimension (sqrt(23)/sqrt(7)). And the article quotes people saying that the field of view is comparable to other headsets.

The Quest 2 has a PPD of 18.88 horizontal and 18.69 vertical. The article also mentions the Quest Pro as having 22 PPD.

But this article is claiming that by their calculations, the Vision Pro has "50 to 70 PPD", which is supposedly in the ballpark of the PPD of the fovea which it says is around 60.

If the Quest 2 is 18.8, and the Vision Pro has 1.81 as many pixels in a dimension, then the PPD of the Vision Pro should be around 34. Nowhere near "50 to 70".

Did the authors forget that PPD is calculated along one dimension only, rather than two?

I mean, the resolution is a great improvement, but it's not "retina-level" yet. It's halfway there.