[3] Petersen's main influence for becoming a photographer was his mother Ester, who he often saw developing glass slides at their family home.

Entitled I'm Late, the photograph depicted a running karoro (southern black-backed gull) at Muriwai, winning a prize in the William Davies Memorial Salon (Natural History) 1956.

[9] In 1961, Petersen, won joint first prize in the Teal 21st Anniversary Photographic Competition for Morning Calm, a shot taken of Milford Sound / Piopiotahi at dawn.

[7] Throughout his life, Petersen documented events for the Swanson community, such as school galas, birthdays and weddings.

[14] In 2020, Olaf Petersen's photographic collection was added to the UNESCO Memory of the World Aotearoa New Zealand Ngā Mahara o te Ao register.

[15] In 2022, a survey exhibition was presented by Auckland War Memorial Museum, curated by Shaun Higgins, accompanied by a substantial book published by Auckland University Press with contributions from Higgins, Sandra Coney, Sarah Hillary, Andrew Clifford and Kirstie Ross.