A rule prohibiting photographs in the Senate chambers was suspended to allow for this modest first official group picture on September 24, 1963. I'm disappointed they didn't go with the laser backdrop.
The photo-session, for the National Geographic Society’s illustrated book on Congress, We the People, was scheduled before the historic vote on the Nuclear Test Ban Treaty. Ninety-eight members took their seats at 10:15 a.m. Photographer George Mobley set up three giant reflectors containing 21 large flashbulbs. Following each of six exposures, the burned-out bulbs had to be replaced for the next shot. During one exposure, a bulb exploded and showered glass onto spectating Representative Fred Schwengel, founder of Capitol Historical Society which sponsored We the People.
Compare this with the toothy mugging that takes place today as soon as any camera is raised.