WIP: an unnamed world for training purposes.

I have started a new world from scratch with just random PS-clouds and I'm then trying to figure ways to create a world from there.

PART 1:
Basically I generated three layers with black/white render/cloud-filters and added these over each other by trying different transparency or blending options until I had a shape of greyscale topology I liked. The render/cloud-filter always renders the same scale of fractal which makes the over all distribution a little too even. So I scaled the top layer 500% and moved it around until I got som continent like lighter blobs on my workspace.
There was a lot of trial and testing in these steps, but I ended up with this.

Attachment 38044

The top adjustment layer enhances the contrast (in this instance I used /levels restricted to the upscaled top layer only) so the shapes become better defined. I then painted the adjustment layer-mask by hand with a broad soft brush to enhance where I wanted the continents.

Then I tried to figure at what level of grey I wanted the sea level to make the prettiest shape for continents. I used select/color range and picking one of the brigter areas and then moving the fuzziness gauge around until I was satisfied. I finish the selection and enter quick mask. In quick mask you can increase the contrast by tool of choice. I use levels here to keep some control over coastline antialiasing. I want it sharp, but not 2-bit-sharp which will end up with ugly pixelized edges when I use stroke on the coastline later.

Attachment 38045

Some manual painting and editing was done to remove unwanted islands and objects that crossed the edges from the selection.

At this stage I copy the landmasses and the seas to different layers so I can work with them separately from now on. The water layer here is tinted blue at this stage for visility only. The lakes are hand painted to a darker color in the tinting layer only because I want to separate them from the oceans. It is a good idea thing to save the continent selection to an alpha layer at this point.

Attachment 38046

I'll continue with Part 2 in this same thread within short. But don't wait for it. I'll be happy for all tips and comments on this part before the next is finished.