NEW YORK — Most artists, especially those trained in art schools, begin their careers with representational art rooted in realism. Some shift towards abstraction, but only after cutting their teeth on figurative and naturalistic works. Self-taught American painter Roy Ahlgren (1927-2011) found himself immediately attracted to the dramatic style of Op Art, which is short for optical art, a form that relies on and plays with optical illusions. He is known to have created about 1,000 artworks in this alluring style from 1965 to 2010.