She was surprised with her win because she has only been studying photography this year.
"My teacher is amazing."
Despite her success, the 17-year-old isn't contemplating photography as a career, her plan is to study nursing.
Stills had more than 1250 entries nationwide from Year 1 to 13 student photographers. The competition is run by RQP - the team behind the hugely successful performing arts platform Smokefreerockquest. It was judged by top New Zealand photographers and visual artists Edith Amituanai, Conor Clarke, Chontalle Musson, Christian Tjandrawinata and Canon representative Geoff Ball.
Judge Conor Clarke said: "Everyday items paired with a simple mirroring technique for maximum effect. It suggests to me that no matter where you are in the world, markers of your cultural identity are everywhere. Ka pai Ella, a strong and creative work!"
Book Tiki has already been on display at Te Papa in Wellington. Ella was one of six William Colenso College students with work featured in the Ringa Toi student exhibition, a celebration of toi Māori co-ordinated by the New Zealand Qualifications Authority.
The six Colenso artworks will be seen in Hawke's Bay along with the best of the region's secondary school Māori art from December 5 to 10, when Ngā Ringa Toi o Te Matau a Māui is on show at Hastings' Akina Gallery.
■ Framed prints of Ella's Book Tiki can be ordered for $100 from the William Colenso College office by phoning 06 8310180.