 His father Pierce Mott Cazneaux was an English-born photographer and his mother Emily Florence was a colourist, miniature painter and photographer from Sydney.In the 1890s the family moved to Adelaide and Harold started to working in his father's studio and attended H. P. Gill's evening classes at the School of Design, Painting and Technical Arts.In 1904 he decided to move to Sydney where he took up a position with one of Sydney's oldest photo studios, Freeman & Co. Clearly he was good at the job as he was later appointed the firm's manager and chief operator.