Comment by BearOso
5 days ago
At the traditional 96 dpi, you have to be 3 ft away to exceed the retinal density. Personally, I sit at half that distance. Something around 200 would be more ideal. Laptops you might sit even closer.
Mobile devices, unless you get really close to the screen, have matched the retinal density for a while. Most people hold the device at about 8 inches, so 450 dpi is the value to hit.
Edit These measurements assume 20:20 vision, which is the average. Many people exceed that. So you'd need slightly higher values if you're feeling pedantic.
Having the focal point up close for a long time isn't that good for the eyes, so sitting closer than an arms length to a desk monitor isn't an idea that lasts well.
100 dpi with subpixel rendering already maxes out angular resolution (horizontal). It doesn't max out everything (retinal), so you still see some artifacts, but practically this is not that relevant. The price in energy/bandwidth rises quadratic for very little gain.
To get the equivalent of 4K at 100 ppi - with 200 ppi you have to put the burden of 8K onto the GPU... For now this is absolutely not good - High ppi is ok for small monitors and handheld devices, but for a decent desk with several good monitors GPUs just aren't ready yet.