“Put yourself in the position of the average person going to Jones Beach for the day,” the photographer Joseph Szabo said the other day. “You see the lifeguards on the stand, but there’s certain things you don’t see about them. “The average person is not going to be invited to lifeguard shack, where they have their lockers and they talk. And you’re not going to see the power nap, after they made five or six saves that day.” Mr. Szabo, who started photographing at Jones Beach almost 50 years ago, was initially drawn by all the pageantry of humanity on display there. Whenever he shot, he would check in with the lifeguards, ask them what was happening that day, how many swimmers they had pulled from the surf. He had been a lifeguard at pools in Ohio, but Jones Beach was different.