Son Doong is one of the world's largest caves, with enormous chambers that can comfortably fit a 747 airplane or an entire New York City block full of 40-story buildings. Its mammoth chambers extend so far that explorers have called Son Doong an "infinite cave." And with an amazing new digital tour, you can plunge below ground to see it yourself without ever leaving the country.
Pictures have offered stunning peeks into the cave, which is located in central Vietnam's Phong Nha-Ke Bang National Park, since explorers discovered it in 2009 with the help of a local guide. But the attention of curious sightseers is a double-edged sword; planned construction projects to make the cave more accessible to tourists could harm the formation's unique environment.
Photojournalist Martin Edström hopes to bring the cave to as many people as possible. He also wanted to document Son Doong in its relatively untouched state, just in case those construction plans go through. So he set out with a team in January 2015 to build a virtual tour of this roughly 2.5-mile-long (four kilometers) cave.
Digital "tourists" can mouse through 360° panoramic views of key sections of Son Doong on a smartphone, tablet, or desktop computer (see above). Some of the largest passageways are about 300 feet (91.4 meters) wide and over 600 feet (182.9 meters) high.
Edström, whose work has been supported by the National Geographic Society's Global Exploration Fund, discusses the challenges of taking on such an enormous subject for his photography.
You've expressed reservations about inserting a cable car and other features for tourism in the cave. Are you afraid that publicity will drive those plans forward?
The best thing for this cave would probably have been to not be discovered. But of course, that doesn't do any good either. We want scientists to be able to study it, and we want people to go enjoy it. But that doesn't mean we have to do it irresponsibly.
Of course we should make it easier for people to go see it. That would help local communities because they will get more tourism business, which is important. But it can't be done in a way where we suddenly go from zero visitors to a hundred thousand a year. We have to make sure the cave is preserved as much as possible.
Why did you decide to do an interactive experience rather than just take photographs or shoot video footage?
I work with interactive journalism because the end user gets a much more immersive experience—it's possible to get people to walk through the cave as if they were there. You can get the reader into the story and get them to explore it actively.
We have [also created] a small archive that shows the cave as it was when we were there in January 2015. So we have a digital copy of the cave in case it's destroyed.
How is this cave project different from your other projects?
Everything was huge and majestic. It was very difficult, logistically, to plan.
In what way?
First of all, the lighting—you have to light up a completely dark cave. For still photography or videography, you have to light in one direction. But for 360° views, you have to light in 360°.
We have to make sure we light all around us for when we shoot. That's what took all the time.
How did you light such an enormous space?
First, we got some fantastic strong lights from a small manufacturer from the Netherlands—the most powerful portable LED lights I've ever seen.
And then three of my team were just running around the caves with these lights. This cave is several kilometers long, and we had to spread out and light this cave from all different angles.
What about the cameras?
We had a massive camera setup. I think we brought 25 cameras of different kinds. It ranged from a small, quick-and-dirty solution—like dropping a camera on a tripod—to bigger cameras and a better lens to cover more areas.
Were there any surprises?
We had many logistical problems. Getting [equipment] through the airports was fine until Vietnam—they wanted to take all of our tripods. So I had to engage in some soft diplomacy to get the tripods in.
In the cave, even though we had planned extremely well and tried to understand the distances, we really had no idea how absolutely, humongously large Son Doong is. It was crazy.
We were extremely lucky in many ways. The weather was on our side, and no one broke an ankle.
What is it about seeing something?
It's not so much the visual power but the control. Modern journalism, it's linear. You read a text from point A to B, or you watch reportage from start to finish.
But in this [interactive experience], you become an active explorer, an active user. If you don't explore the story, the story won't happen.
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