This is a project for a client i had some fun with. It's pretty interesting all the possible coastlines revealed by adjusting the elevation. The job called for a somewhat familiar, but notably different, earth.

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I started with a high res elevation map (from Tom Patterson's excellent site), and painted with 1% transparency in white and black, to raise up the sea floor or drown the land. I wasn't too scientific with the plates, though when moving chunks of the world around i often divided things on actual tectonic boundaries. My biggest deviation from reality was breaking the Andes in two. South America's western side looked pretty much the same through huge adjustments of the sea level, and i wanted more variety, so i sunk it to a depth much, much greater than the changes i made elsewhere.

The coloring was a messy combination of gradient maps, masks, and blending mode overlays. I think i ended up with something half-way between a topographic map and a NASA view-from-space, though i had planned to go a bit more toward the satellite look, but it works.