Originally Posted by markmon1
I realize from your logic it's not a good test. But to get an idea of the distance to see the difference between 4K eshift and native 4K (which is what we were talking about), it's a pretty good test. It just so happens to coincide to about where I need to be, when wearing my glasses, to see that difference.
Logically, I think it makes sense if you use your value of 10% pixel gap at 1080p. The 4K would require the pixel gap to be 25%. But eshift is about double the resolution of 1080p so that 25% can be cut in half which is then 12%, which is very close to that 10% that you said above.
No, it doesn't make sense; fill ratios are based on area.
I think I recall the fill ratio for 1080p panels is something like 97% and for 4K panels something like 95%; but even using something extreme like 90% and 80%; I'll work it through.
Imagine a 16:9 screen 1920mm wide.
Each pixel including the inactive region is 1mm x 1mm (1mm2).
90% fill of 1mm2 is 0.9mm2
sqrt (0.9mm2) = 0.95mm sides of the active area.
1mm - 0.95mm = 0.05mm gap between pixels.
Now that same width screen 1920mm would have 0.5mm x 0.5mm pixels (0.25mm2) (I'm overscanning the DCI extra pixels for ease of calc to get a 16:9 image)
Say fill at 4K is only 80% fill:
80% fill of 0.25mm2 is 0.2mm2
sqrt (0.2mm2) = 0.45mm sides of the active area.
(you'll note the pixel gap remains the same at 0.05mm - this is what you'd expect as the tech hasn't managed to improve that I believe).
You can see the size of the pixel gap at 1080p is 9 times smaller than the width of a 4K pixel for the same projected 16:9 image size. Hence the point at which you stop seeing the pixel gap is not relevant to your ability to resolve 4K.
If you spin it round the other way though it does work, if you can see the 1080p pixel gap from where you sit you'll definitely get the benefit of 4K (in fact I think
you'd get the benefit of 16K(!) at that distance).