En Plein Air simply means to draw or paint outside, observing your surroundings as you create.
It is not En Plein air if you paint a landscape from a photograph!
Painting En Plein Air is a tradition that began in the mid 1800's for artists to practice painting the outdoors in different types of light. The artists most famous for for painting En Plein Air are the Impressionists. Monet is a well known impressionist painter.
Claude Monet
Examples of En Plein Air Painting
Mrs. Pearl Maggie Puetz