My grandfather was an insurance agent when I was a kid. I remember one summer riding around in his Lincoln, taking Polaroid snapshots of houses for new homeowner's insurance policies.
If you leave a stack of Polaroids in the sun in a hot car while you stop in at Burgerville for milkshakes, the colors tend to separate. Check out what photographer William Miller has done with Ruined Polaroids and you'll get a feel for what I am referring to.
The ghostly effects somehow felt more true to me than the ones that turned out as expected. The shifting colors hinting at the movement and energy in picture. When I started exploring layering and glazing with watercolors, I noticed a similar effect happening. The multiple layers of colors shift and move and give the subject life.
You can see this process in this series of photos of my painting, Dearest One, here. Ruthie on the right begins with a first layer in yellow, then I added a cobalt turquoise and a layer of red, then finally a layer of dark darks in one of my favorite greens.