I am also informed by Art History. While getting my masters in Photography, I had to take 6 years of Art History. I start by understanding what the artist was trying to accomplish. This is a large part of it.
And to be fair, I do my best to hold on to the painting for as long as I can to let the colors seep into my brain, and whenever possible, keep it until I am done printing. (Or borrow it when I am ready to do the final.)