 A representative example of Huebler's early work is Duration Piece #5, 1969, a series of ten black & white photographs with accompanying text; to document the piece, Huebler stood in Central Park and, each time he heard a bird call, he pointed his camera in the direction of the call and shot a photograph.In 1971, he began "Variable Piece #70 (In Process) Global," for which he proposed his intention "to photographically document the existence of everyone alive.