Very carefully, with a rag in my left hand to wipe out the charcoal and my brush in my right hand, I follow the lines a little bit at a time. I am using burnt umber with Liquin, diluted with mineral spirits to follow the fat over lean regime.
I add some darker values on the roofs so I an get an idea where I'm going. This is such an important stage. If I don't like it at this point, I sure won't like it when I get color on it.
At this point notice that I've moved some windows...the top left one was further to the right, the second one down was barely noticeable because of some tangent lines, and the one at the lower left didn't even exist.
|The burnt umber under-painting|