Working through the tutorial right now, and on the first step there is a tricky thing for GIMP users.

We do NOT have a threshold adjustment layer.

I have been able to get a similar effect by simply duplicating the "background" layer and then running the threshold adjustment on the duplicate.

The annoying part is when I get to editing the image (removing or adding land), I am flying blind. I can edit the original cloud image, but I do not get a real-time view of what my brush strokes are doing. So, my first attempt left me with some areas that were too rounded for my taste.


I think this can be worked around, it just involves a bit more of a time commitment from GIMP users.

Perhaps a more experienced GIMP person knows of a better way to work around the lack of Threshold Adjustment Layers. There are on plugins that I can find.


On to the next step!