Sometimes I go and paint oils with my friend Christine at her studio. I bring over my plein air easel and supplies, and we work side by side, chatting and listening to music. Today I accidentally left my reference materials at home, and so had to paint from memory. It was a bit difficult at first, as I kept changing my mind as to color and composition. When this happens, I just rag off the paint and start over, but then I have to contend with the fact that the canvas has lost much of its "tooth", and subsequent layers of paint smears and feels all slippery.
Nevertheless, I was satisfied that the painting ended looking somewhat close to what I'd imagined.