I hand painted most of the background, some clouds, the colors, the haze... the clear cloud on the top right and some on the back ones are tweaked photographs. The planets (moons?) are modified images of our moon mapped on geospheres. This is pretty simple, the back plate looked like this:

I think there's a useful thing to note here. I chose a vertical image (rather than the typical 1.333 image aspect) because it's easier to use as a poster or a cover. The final image resolution is 3000 X 4500 pixels.
 
Now that I have something to use behind my terrain I set up my scene. Remember that I told you that I consider the use of displacement maps as a modeling technique? Well, I think I can make my point here. What you see is the actual scene, there is nothing but a fraction of a sphere. I didn't move a single vertex to make the terrain.
 

To be consistent I merged the lights from the island file and placed my sphere basically in the same place as the island in the other scene.
 
I used 3 textures for the terrain mapped with a planar gizmo: a color, bump and displacement map. I chose to use a bump here because due to my time limitations I could not use very high values for the displacement subdivision in the terrain so I needed it to look a little more detailed. It took a lot of tweaking to make the river look right, I had to find a good balance between the bump (as in the foam and little waves) and the displacement. Basically the same rock textures I used on the island I applied to these maps along some other dirt, hand painted grass and masks.
 
The terrain is a little arid so far, remember what we said about using our story to build our scene? This planet's atmosphere and surface are still under construction, give it a couple of hundred years and it will be a forest.
 


The river is 100% hand painted. Here are the basic steps for doing it.

Step 1: First paint the basic shape with a light blue and add a little texture and some light.

Step 2: Add the rocks beneath it as you don't want it to look like ir just runs over the grass. Play a little bit with its opacity and saturation.


Step 3: Add some dark blues and greens.

Step 4: And finally paint some foam and waves wherever the water hits a surface as a rock or the walls or where you feel like a little waterfall would look right. And you're done!


This is the result:





I made two other minor islands for the background. These are variations of the first, they needed more time than I thought. Both have some texture stretching problems but they would be far away so it's ok, they didn't need displacement maps either just bump. I used the same plants rendered for the main generator with some deformations. The tree on the top on one of them is a photograph I took against blue sky, this helped to apply a mask to it easily. I had to add some shades, lights and color correction to the tree so it would match my palette.



Now for the waterfalls.

I searched the web and found a lot of images that looked the way I wanted mine to. I found that when high volumes of water fall down they tend to form kinf of "V" shapes before it starts to dissolve into veils. So I made this image and mapped it onto facing faces on a particle system on the opacity channel.

This is my gift to you out there, if you can find a way to use it be my guest.

As the waterfall goes down I used the blur tool and the eraser to fade them, then I applied some brush strokes and blurred them to make it seem like wind was taking this veils away.


Finally I added some stars, a little color correction on the islands (they were too yellow), the fog, the rainbow, some extra shadows on the world below (casted by clouds and the islands themselves), little touches on the shadows casted by the plants over the generators, little highlights on the river, some extra colors on the eyes of the faces and a couple of extra general touches.

And that's it!

Well, I hope this helps. If you would like to see more about something drop me a line. Comments and critiques are always welcome. C ya!