Exterior screen shots from the "Aries" games project, I was the Art Director and Lead Environment Artist. I created all the alien architecture using Maya and Zbrush as well as using Photoshop for texturing.
The mountains where made in Vue 8.5; retopologized and normal map baked from the high poly Vue model. There are some work in progress images from this work flow in the blog here: http://ryanwwatkins.blogspot.com/2011/04/vue-to-udk.html
The sky was also created in Vue and rendered out as a dome.
All the the Vegetation is from the UDK and SpeedTree.
Images are real time renders from the UDK