I recently started on a small island myself, my first project for Arma 2 mapping.
Now I tried converting my satelite image to a height map, didn't turn out that well. So I was wondering if it was possible to draw the height map yourself, with a program such a Photoshop or GIMP? I'm using a real world satelite image as the template for it.
This is an example of what I mean:
(this is very early stage, not even near final result. And only a part of the entire image, in case someone wonders about the size)
Would that be possible? Or rather, would it work?