Hi, I see a lot of confusion on the forum when you try to compare the preceived resolution of the screens used in VR headsets.
PPI is good but only for display monitors, so I’m proposing a new measuring unit
SPD - Subpixels Per Degree
It takes into account the resolution of the screen, screen type (RGB or Pentile) and viewing angle.
The resulting value is the amount of physical sub-pixels visible in the angle of 1 degree (not in game rendered pixels)
That’s why the new unit should also be calculated based on the sub-pixel arrangement as the difference between RGB and Pentile is quite significant 33%
There is a lot of confusing info on the forum about Pimax 5K and no clear answer from the Pimax team, so I’ve decided to include both display options on the graph. I will update the graph as soon as Pimax gives some official specs.
The formula is on the bottom of the table in my second post. To calculate it properly you have to take per eye resolution, not a total of pixels of the panel.
This article does not take into account the sub-pixel arrangement which is the reason why PSVR has better perceivable image quality. So again I would like to emphasize that my way of calculating the SPD is superior.
Of course there is another factor, the subpixel size (less black border around the subpixels). That’s why you can see the difference in the screendoor effect between Rift and Vive