User blog comment:X-Machinist-X/Dishonored random stuff/@comment-1500935-20151121222807

Just stumbled across this: Opus Artz, a London based production design agency, did some work on Dishonored for pre-production environments and promotional key art. You can see the five concept arts they uploaded on this link: http://www.opusartz.com/category/project/dishonored/

I think their depiction of Dunwall's environments is closer to the City in the latest Thief. Dishonored in the end had a larger palette of colors.