The graph suggests that you should be looking at a 65-inch screen from a distance of 120 cm for resolutions above 4k to be worth it. I interpret that as the distance at which the screen-door effect becomes visible, so this seems awfully close actually.
A 65-inch screen has a width of 144 cm, which gives you a 100 degree angle of vision from the left edge to the right edge of the screen. Divide the approximate horizontal resolution of 4000 pixels by 100 and you get an angular pixel density of 40 PPD (Pixels Per Degree).
However for the pixel gaps to become too small to be seen or in other words for the screen-door effect to disappear, you need an angular pixel density of 60 PPD. That means you can sit at a more reasonable distance of 220 cm in front of a 65-inch screen for resolutions above 4k to be worth it.
This is still too close for comfort though, given that the resulting horizontal angle of vision is 66 degrees. The THX cinema standard recommends a horizontal viewing angle of 40 degrees.
So multiply 40 degrees by 60 pixels per degree to get a horizontal resolution of 2400 pixels. That means the perfect resolution for TVs is actually QHD.
That means the perfect resolution for TVs is actually QHD.
And yet QHD would be comparatively awful for modern content. 720p scales nicely to QHD, but 1080p does not. I suspect that’s why 4K has been the winner on the TV front, it scales beautifully with both 1080p (4:1) and 720p (9:1) content.
That graph is fascinating, thank you!
I don’t think it’s correct though.
The graph suggests that you should be looking at a 65-inch screen from a distance of 120 cm for resolutions above 4k to be worth it. I interpret that as the distance at which the screen-door effect becomes visible, so this seems awfully close actually.
A 65-inch screen has a width of 144 cm, which gives you a 100 degree angle of vision from the left edge to the right edge of the screen. Divide the approximate horizontal resolution of 4000 pixels by 100 and you get an angular pixel density of 40 PPD (Pixels Per Degree).
However for the pixel gaps to become too small to be seen or in other words for the screen-door effect to disappear, you need an angular pixel density of 60 PPD. That means you can sit at a more reasonable distance of 220 cm in front of a 65-inch screen for resolutions above 4k to be worth it.
This is still too close for comfort though, given that the resulting horizontal angle of vision is 66 degrees. The THX cinema standard recommends a horizontal viewing angle of 40 degrees.
So multiply 40 degrees by 60 pixels per degree to get a horizontal resolution of 2400 pixels. That means the perfect resolution for TVs is actually QHD.
There’s obviously truth to there being diminishing returns, but this chart is garbage.
And yet QHD would be comparatively awful for modern content. 720p scales nicely to QHD, but 1080p does not. I suspect that’s why 4K has been the winner on the TV front, it scales beautifully with both 1080p (4:1) and 720p (9:1) content.