Her mother encouraged her photography, organising lessons with Victor R. Millard on photograph retouching.

[2] Harper began her career in photography when she was eighteen years old at the studio of H.J Schmidt in Queen St, Auckland.

[2] She became widely known for her formal portraits which captured major life events for her customers.

[3] In 1945, Harper helped to establish the New Zealand Professional Photographers Association and was subsequently made a life member in 1975.

Harper's collection of work has been exhibited at the Auckland War Memorial Museum in an exhibition titled Reflections; New Zealand Women's Lives Presented Through the Collections of Auckland Museum in 1993.