This is one of my favorite activities when it comes to digital painting techniques: take a picture of something, anything, and turn it into something wildly different. Digital manipulations gone wild.

Example:    

my morning cup of coffee has a lot of frothed foamy milk, bubbles that burst, sometimes they haven't burst yet, but it looks so great, looks like the impact craters on the surface of Mercury or the Moon. We can take it further and combine it with elevation maps of deep valleys or mountains, rolling hills and crevasses from ancient volcanic activities. Add erosion, from rain or other effects, ... even of course paint your extra details, subtle river beds and deltas, glaciers, rocky bumps, or hints of stratification layers... it is after all a paint program :-)


Here's an example you can play with:



You'll probably want to remove the bright highlights from the kitchen lights, unless you want some extra special pilar structures in that elevation map. Very cool too!

You'll want to make it into a greyscale and make it seamless. If you want the craters to stand out, use the embossing filters or the edge detection filters to isolate some of the crater's rings and slightly blur or sharpen them (or both) and combine them in additive more or screen mode or other modes.

In the Stylize group of filters, use the Erosion tool to add an erosion map.

And also colorization with the Slope shader, which picks colors from 3 sets (white snow at top, green down low and grey rocks in middle - but it's fully customizable). The colors are assigned based on the elevation and changes of it, the slope. Blurring or non-blurring can be very valuable. Shading too. Try the option.

Here are examples of images created from that cup of morning Joe:




Here's a lengthy detailed tutorial that shows some of the techniques:




Here are a few sample renderings done in this way:
















And finally this, where you can still see the impact craters: