This is really interesting. They colorized a photo by overlaying some lines in a grid and ONLY adding color to the lines but oversaturating the color. The rest of the image is black and white.
The result is that at a distance or in the thumbnail it just looks like an ordinary color photo. It is only when you look up close you notice what is going on.
@freemo this is fascinating. I wonder what inspired this idea.
@Liberonscien It was in a study i read a while back and honestly cant remember the details. I found it hiding on my system from when I shared it on facebook a while back.
There are some non-primary colors used int he image as well.
I do find it interesting that red behaves differently, though not surprising. Our eyes do tend to notice red more strongly than other colors.