Wow, i love the combination of so many stocks. It looks like on photo. I used one of the waterfalls in one of my pieces. lol. I love it. Very good and has lots of depth.
It wasn´t that difficult, first I just got a pile of stockphotos that had allmost the same atmospherics (grey sky, allmost the same shade of green etc.), and then just compiled it. Used a large eraser on the edges on most of the pictures, since there was a lot of greenery underneath everything, so the large eraser was enough. Only needed to be a little more carefull with a couple of the waterfalls. And also, if the green shades differed too much on some parts, I just added a colorlayer on the problemparts, and then painted it with the right tone, while desaturating the original (wrong) tone so it wouldn´t show.