Their mother, Sarah Jane née Hellyer, was born in New Zealand, while their father, Robert Walter Moore, originally came from England.

[3][4] Sometime in 1906 – 07, May began to earn money from her work, selling ink and pencil sketches at the New Zealand International Exhibition (1906) in Christchurch.

[2][4] Since they did not know how to run a photography studio, the sisters initially kept on the staff, who trained May in camera operations and Mina in printing.

They became known for close-up, side-lit portraits shot against a plain background, and they worked with both sepia toning and bromide paper.

[3] One exception to this rule was her husband, Henry Hammon Wilkes, a dentist whom she married on 13 July 1915 and who gave up his dental practice to help his wife with her photography business.

[2] In 1913, Mina joined May in Australia, setting up shop in the Auditorium Building on Collins Street in downtown Melbourne and specializing in theatrical photography.

At that point she was working out of a home darkroom and caring for an expanded family, so after the Shell series she decided against restarting her photography business.