This project is a practice and testing piece (http://forums.cgsociety.org/showthread.php?f=43&t=1253030) on hardsurface sculpting and PBR texturing. Primary motive was to work on hardsurface sculpting workflow, retopology and setup a game-res model for PBR testing and rendering. The helmet model consists of several parts: helmet, visor, jaw and sensors. This allowed for different variations of the same base textures and facilitated look development. Several HDRIs and lighting setups were tested with the PBR textures. A final beauty render was done to finish off the project.
Tools: ZBrush, 3D-Coat, Quixel, Blender/Cycles, PS. PBR tests images all rendered at 400 samples. Beauty render at 500 samples. HDRI largely from sIBL archive.
Apologies for resurrecting this thread. Just wanna say that hi-res prints of the image in OP are available for sale at Redbubble. A portion of profits will go toward the Blender Foundation in the form of add-on purchase/donation.