The most serious issues have been worked out now. Here is the last render I created.
The normal map is solved. World Machine uses a Direct-X normal map, so I need to invert the Y-channel to get the OpenGL normal map format. The end result is better looking erosion lines that no longer appear to be vascular pumped veins throbbing across a power-lifter.
You will notice some odd stretching in the sky. That problem is also solved – I just did not upload a new version to Flickr. As it turns out, Image World is not the best answer for displaying HDRI sky domes. Image World is best suited to HDRI light probes and is not usually meant to be seen in the final render. I am using a Textured Environment using spherical projection for the sky dome now. That correctly renders the sky and clouds without distortion.
In a very happy accident, I began exploring the new GeoGlyph 2.0 plugin for World Machine. Taking a cue from the work on “Sandstone Ridge,” I wanted to enhance the look of the erosion lines and get a more rock-like look to the terrain.
What came out immediately reminded me of some non-terrestrial planetoid. I instantly imagined a star field and nebula instead of an Earthly sky dome.
I also wanted to use the erosion to hint that there may be something else below the surface. So I made that a yellow-gold blend to mix with the brown and grey of the rock.
Instead of Textured Environment, I simply created a huge rectangle to act as a backplane. There is a slight curve to it but I don’t think that comes through in the picture. I used the Filter Forge plugin for Photoshop to create the star field and nebula.
Since it is in space without any atmosphere, the key light is a Distant one. This creates very hard shadows and you can see the light angle puts much of the left-side terrain into darkness. Behind the camera is a very large Area light that uses some of the green colour from the nebula. This light is very faint but it fills in some of those shadows a little bit.
I think it is time to return to building my skills with Poser and ZBrush.