Roger Steffens is many things: father, veteran, actor, writer, broadcaster, and an expert on all things reggae. He first picked up a camera during the Vietnam War, but not as a photographer — as a witness. “My grandfather and mother had a keen sense of history,” he said. “They both instilled that sense in me that there were things going on around us that would be looked back upon as historic.” Steffens went on to take some 400,000 images during the height of 1970s counterculture, capturing his growing family, spectacular strangers, and the celebrities he came across. “The kids never knew who was going to be knocking on the door,” he said. “I’d say ‘Come out and meet Burning Spear,’ and they’d say ‘Dad I gotta do my math.’” Steffens let the images linger until his children Katherine and Devon started scanning his archive and sharing their family memories on Instagram with the moniker “The Family Acid,” (Steffens met his wife, Mary, during an acid trip in Mendocino’s pygmy forest). A selection of the images will be on view at New York City’s Benrubi Gallery beginning July 7 — Steffens’s first exhibition — and he has shared some with The Atlantic below. The captions were provided by the gallery.