Drawing on the subtlety of light and atmosphere of the Hudson River and Luminist schools, John Atwater captures the beauty and life of coastal landscapes. Since 1980 he has spent a number of weeks each summer sailing and driving along the Maine coastline, from Boothbay Harbor to Camden, gathering research material for his paintings, which he completes in his Connecticut studio.    John Atwater is a member of the American Watercolor Society, American Society of Marine Artists, and president of the Connecticut Watercolor Society. He has received awards in the 1985, 1988 and 1989 American Watercolor Society Exhibitions and his work is displayed in the permanent collection of the Mystic Seaport Museum.    Born in 1954, Atwater studied at the Washington University School of Fine Arts in St. Louis, Missouri and worked as a commercial artist eight years before devoting himself full time to painting. The New York Graphic Society has published three of his paintings and his work is featured in the books Marine Painting, and Splash-America's Best Contemporary Watercolors. Articles on his work have also appeared in American Artist, Yankee, Connecticut, and Motor Boating and Sailing magazines.