Never-before-seen footage showing the aftermath of the 1931 Napier earthquake has been unearthed from a stack of rusty, dust-covered film cans of a Manawatu photographer's estate.
The tins containing the film were uncovered in 2017 when a garage at a property in Trentham, Upper Hutt was cleared in the process of sorting through the estate of a relative of Thomas Henry Whetton, a Whanganui-based freelance news cameraman active in the 1920s and 1930s.
Retrieving the footage was a painstaking process for the team at Ngā Taonga Sound & Vision, New Zealand's archive of film, sound and television.
Not everything could be recovered, but what was able to be preserved and digitised is now the feature of a new exhibition; Rust + Restoration – He Waikura He Whakauka.
Kate Button, Principal Project Manager for the exhibition said a member of the family contacted Ngā Taonga Sound & Vision when they realised what the tins contained.
"Thankfully, Whetton had labelled his material in considerable detail and it was therefore relatively easy to identify the events depicted in the films, particularly the Napier earthquake footage."
The tins – mostly film cans, but also some improvised containers like old tobacco tins – probably had not been opened in over 80 years, Button said.
Their film conservators had to prise some of them open.
"The film stock was all nitrocellulose - 'nitrate' film. Even when stored in dry and cool conditions, nitrate film can decompose.
"The decomposing film first becomes sticky, then congeals and finally crumbles – it also smells like rotten meat. Fortunately, much of the material in the Whetton collection was in very good condition," she added.
Their archivists then did an extensive amount of preparation work, with the film thoroughly cleaned to remove sticky parts, frames and sections repaired and additional blank film "leader" added to the beginning and end of each reel.
Following this delicate and methodical work, scanning the Whetton collection could begin, Button said high-resolution scans were taken of every frame, and image stabilisation and colour grading was applied.
"These digital files were uploaded to our digital archive and backed up on servers and archival tape storage. The original films are stored in our nitrate vault."
The exhibition, which opens on Tuesday, in Te Puna Foundation Gallery on the ground floor of the National Library, features film, sound and displays illustrating the Archive's work to rescue precious film, TV and audio recordings from oblivion through the processes of collecting, preserving and digitising them.
Visitors to the exhibition will be able to see how the film found within the cans was preserved and digitised.
Excerpts of the high-quality Napier earthquake footage are included in a looped 20-minute programme projected on the gallery wall.
Other excerpts include film dating back to 1900 and later works of national cultural significance, such as PATU! and the TV series Waka Huia.
The exhibition also presents related highlights from the Ngā Taonga audio collection.
Ngā Taonga acting chief executive Honiana Love said: "preserving film, video and sound for future generations is a race against time".
"In many ways, it's a miracle that we were able to salvage anything from the rusty cans of the Whetton collection, and it's a triumph that we succeeded in saving so much."
Love said exhibition will tell people about the decomposition of nitrate and acetate film stock and will show how more recent media is also at risk of being lost, as the machines that can play videotape wear out and can't be replaced.
Videotape itself degrades and audiovisual archivists agree that tape not digitised by 2025 will in most cases be lost forever.
"Other kinds of documentary archives can be made more stable and long-lasting, but some audiovisual material has a tendency to fall apart all by itself," Love said.
"Rust + Restoration tells the story of how we need to act before the faces, places and voices recorded on vulnerable media disappear forever."
Entry to the exhibition is free and it runs from October 11 until February 22 2020.
You can find more information about the exhibition at: www.ngataonga.org.nz/RustRestoration