Director James Cameron launches deep-sea exhibition at Dunedin's Otago Museum

Oscar-winning director James Cameron has made a rare public appearance at the launch of his new exhibition in Dunedin on Saturday night.

The deep-sea exhibition, titled Challenging the Deep, tells Cameron's story of weaving filmmaking and ocean exploration into a lifelong career.

After breaking attendance records at the Maritime Museum in Sydney, the exhibition has opened in Dunedin. It combines artefacts and stories from Cameron's own underwater adventures with those from his films, including The Abyss and Titanic.

For Cameron, 65, making Titanic was all about exploring the remains of the famous ship. The story of Jack and Rose was more of an afterthought.

"Making Titanic for me was about going to the wreck, imaging the real wreck, exploring it, describing it forensically, understanding the event... and then putting it into a Hollywood film," he said.

That afterthought made millions. Cameron effectively took the next eight years off to learn as much as he could about the untouched and mysterious world of our deep oceans. He says humans know more about space than our own planet.

"You can send cameras and satellites into the air and take photos from orbit but you can't do that here on planet Earth. If you want to know what's there you actually have to go look," he said.

The keen conservationist spends more time at his farm in the Wairarapa than he does in the hills of Hollywood, and is passionate about preserving New Zealand's natural beauty.

He said the increasing effects of climate change has made the exploration of the deep sea all the more important. Cameron believes we can all make a difference.

"We actually have a way of grabbing the Earth's thermostat and turning it back down by what we do... we don't have to wait for our leaders to do it," he said.

As well as his farm, Cameron has another job keeping him in New Zealand.

"I've still got two years just on Avatar 2. We've been filming in Auckland, the live-action stuff, then we will be working with Weta Workshop in Wellington to do all the animated stuff... it's very much a New Zealand production," he explained.

Cameron's exhibition is on display at Otago Museum until February. However, Avatar fans have a bit longer to wait - the next instalment set to be released in December 2021.