Best view distance for your led displays

The most easy way estimate the best view distance is by the distance of two pixel of your led displays, for example: display screen outdoor p10 the "10" means the distance of two pixel nearby,sure,the unit is mm,but you can estimate approximate 10M is the nearest view your led displays,and the 10M * 3 =30 M is the most suitable distance view your led screen,So
display screen outdoor p12 best view distance 12-36m
display screen outdoor p16 best view distance 16-48m
display screen outdoor p20 best view distance 20-60m

May be you will ask how long is the farthest view distance,the answer is that it's decide by your led screen altitude,same example by P10 led displays,if your screen is high:3M,the farthest view distance is 3M * 30 =90M,so the 90m is the farthest view distance. So,finally,we know that

The nearest view distance:  the distance of the pixel+M
The suitable view distance:  the distance of the pixel * 3
The farthest view distance:  the altitude of your led displays * 30