About three times a week, Parra O’Siochain finds himself on one of the outer beaches of Point Reyes, seated near his friend Pam Handleman and armed with a clean canvas and paints. It wouldn’t be unusual if a bottle of imperial ale, cheese, bread and a Frisbee were scattered about while they quietly await a visual. It might be the white waves galloping ashore or a chunk of driftwood: when the muse strikes, Mr. O’Siochain begins to paint. His works, vibrant with color and motion, will debut at the San Geronimo Valley Community Center alongside Ms. Handleman’s. The pair will unveil about 40 paintings each, created during roughly 800 sessions by the sea. “People come out to the beach with their camera at sunset, but if you’re trying to photograph a wave, it’s a wave stuck in time,” he said. “A wave is in motion; the whole universe is in waves. What we’re doing is trying to capture waves. A wave is moving, generating energy and dissipating energy. If you take a photograph, it’s only one moment in time.” Mr. O’Siochain, a Forest Knolls resident who turned 75 this week, said he was approached by Larry Rippee, the community center’s visual arts coordinator, who recognized a personalized touch on a common art form. “Plein air painting and seascapes are nothing new to West Marin, but the continuity Parra and Pam bring to the experience impressed me,” Mr. Rippee said. “The series of paintings almost function as a personal journal. While hanging the show, Parra had a story for every painting.” Years ago, the Dubliner and former motorcycle garage owner developed Guillain-Barré syndrome, leaving him practically paralyzed. He returned to painting after a period of dormancy to help regain his strength and focus and was soon a fixture at the College of Marin art department. There he met Ms. Handleman, an operating room nurse. After an instructor noticed the pair were there five nights a week and taken every course offered, he suggested they move on to the outdoors. “So then we started going to the beach,” Mr. O’Siochain said. “Plein Air Paintings from Pacific Coast Beaches by Parra O’Siochain and Pam Handleman” will be at the San Geronimo Valley Community Center from Oct. 8 to 31. A reception will be held this Sunday from 4 to 7 p.m.