Basic Colour Pass

Lit Colour Pass with no Line Work

Lit Colour Pass with full Line Work

Aaaaand Lit Colour Pass with Line Work set to half opacity

Went back in a re-did that old hallway. Digital like this time round. More to come.
I did a few different passes, I'm still not sure which one I like the most. When these are done, I'll post a final process in my concept art blog
UPDATE: Look down
I threw in some sexy ladies, some nerds and a dude in a space suit.
Without linework

With linework

With linework set to 50%.

I think I prefer it with linework set lower. It looks too muddy/unfocused without any but too sharp and grainy with it all the way to 100%