ok now this is a project i did for a challenge that should be closed by this day on blenderartists.org
https://blenderartists.org/forum/showthread.php?447161-Challenge-769-(16-03-18)-Entries-OPEN
the them of the challenge was helmet . so her what i did
made it with blender 2.79 _ 200 samples + denoiser took me 2h to render it
all textures were made in krita
hope it,s good enough but any way C&C are welcome