Before Avatar sequels, filmmaker James Cameron finishes film on his deep-sea dive to Mariana Trench

The award winning director says leading an expedition team and directing a feature-film crew require virtually identical skills.

The American filmmaker James Cameron after his successful solo dive to the Mariana Trench during the filming of Deepsea Challenge 3D. Mark Thiessen / National Geographic / AP Photo

In the documentary of his record-breaking deep-sea dive, Deepsea Challenge 3D, James Cameron asks: "Am I a filmmaker who does exploration work on the side, or am I an explorer who does filming on the side?"

It's a good question. It's now been five years since Cameron's last feature film, Avatar, and, in that time, the priorities of the most bankable director in Hollywood have sometimes been as murky as the deep sea. He has spent those years producing a fleet of documentaries about ocean exploration and deepwater life forms.

His biggest project hasn’t been a mega-blockbuster, but building a deep-diving sub and piloting it more than 35,000 feet down into the Challenger Deep, the deepest part of the Mariana Trench.

“I make the Hollywood movies to pay for the exploration,” Cameron says.

Certainly, many moviegoers are eager for Cameron to get back on a film set. After some earlier postponements, he's on his way, currently finishing the scripts and design work for three planned Avatar sequels.

But, for now, he's releasing into US theatres a 3-D film for National Geographic that chronicles his 2012 dive into another alien world, "the last great frontier", as he calls the ocean. For Cameron, the movie is a testament to the spirit of exploration, which he feels is flagging in America.

Cameron’s dive, nearly seven miles deep, was only the second manned dive to reach the bottom of the Challenger Deep, the deepest known point of the seabed. About 68 new species were identified from the sub, which was equipped with 3-D cameras.

“I think explorers feel a sense of the sacred,” says Cameron of descending into such a remote abyss. “Something that’s beyond themselves, when they go to a place that’s never been witnessed before and bear witness for the first time.”

The Deepsea co-director John Bruno had to capture it all in stormy conditions and while coordinating 3-D cameras that each took two men to operate.

“The ocean hasn’t read the script, so it’s not going to cooperate,” says Cameron. “And the sub is a bit like a diva movie actress. You’re not always going to get it on camera when you want it.”

The similarities of leading an expedition team and a feature-film crew are, to Cameron, identical. Ever the taskmaster, the documentary shows him prodding his scientists on their timetables. In Cameron’s day job, the interaction would be the same.

Speaking of timetables, there is the pace of work on the Avatar films, which are scheduled for release in 2016, 2017 and 2018.

Cameron earlier said the screenplays (which he's writing with Josh Friedman, Rick Jaffa, Amanda Silver and Shane Salerno) would be finished by the end of the spring, but now says more time is needed to perfect the scripts. "It's going to be another couple of months, I would say, at least," says Cameron. "We will serve no wine before its time and I would be pretty stupid to run off and start shooting Avatar until the scripts are perfect. Whether that compromises our announced release date of Christmas 2016, at this point I can't really say until we break down the budget and schedule."

Cameron says he's working seven days a week on Avatar as the pages "pour in", but with one exception. He's taking a holiday to Tahiti for – what else? – a little scuba diving.

* AP