Watercolors of Robert Becker. This book is a compilation of my recent watercolors. Many of these were painted 'en plein air' a French expression which means "in the open air", and is particularly used to describe the act of painting outdoors. Painting watercolors en plein air is much different from doing a painting in my studio, aside from the weather and ever changing light, many times I have chosen subjects that are not just landscapes and are in constant motion.