Text / Video / Images By Photographer Urs Zihlmann of Cave Photography
We are in the Phong Nha-Kẻ Bàng National Park in Vietnam on an expedition to the world’s largest cave. We are looking forward to a five-day trip into a unique underground paradise. The cave was found by local farmer Mr. Ho Khanh in 1991. It was not until 2009 that the British Cave Research Association explored the cave and it instantly became one of those amazing things you have to see in your life.
In 2014, once the caves had been thoroughly explored, the government granted tour operators permission to host treks through the caves. Since then, about 900 licenses have been awarded, and I got one of those – Lucky me!
Part I: Hang En Cave
To reach Hang Son Doong, adventurers must first pass through the third largest cave in the world, Hang En Cave, which is equally spectacular. The cave was recently used as a movie location for the blockbuster Peter Pan. The unique campsite with sandy beach and two natural pools is worth the trip alone.Check out these #pro tips on #travel photography inside the world's largest cave! Click To Tweet
Continuing On To Hang Son Doong
It took us another half day’s walk in the beautiful jungle, where swarms of butterflies joined us. We crossed many knee-deep rivers and finally managed to get to the entrance of Son Doong after a short ascent. Clouds were rising from the cave into the surrounding forest, caused by the cooler air inside meeting the hot air outside.
We had to descend 80 meters (263 feet) down a steep wall, using harnesses and ropes. Standing on slippery ground in a huge dark chamber, you begin to realize how amazing it is. We had definitely reached Son Doong!
The main chamber is more than 5 kilometers (3.1 miles) long, 200 meters (660 feet) high and 150 meters (490 feet) wide. At this scale, a half-mile block of 40-story buildings could fit inside this lit stretch of Hang Son Doong cave. The cave features two collapsed dolines, or sinkholes, that let daylight in. This has given life to the cave, making it possible for two separate forests to grow within it, a feature not normally associated with the subterranean recesses of caves.
The main cavern is so large that it has its own climate, and clouds have even been known to form within it. The cave inside has some of the tallest known stalagmites at around 80 meters tall. Son Doong is a remarkable natural wonder in many respects.This is what happens when you enter the world's largest cave in #Vietnam Click To Tweet
Our expedition into the cave consisted of more than 40 people, among them local porters, guides, cooks, cave experts and photographers. Tour organizer Oxalis and team did an absolutely amazing job. It could not have been better – even the food in the cave was excellent.
Deb and Howard Limbert led our expedition. Both are members of the British Cave Research Association and they have led all 15 caving expeditions to Vietnam. It was a great benefit for us to have this experienced and knowledgable couple in our team.
Photographing The Underworld
The photography was a challenge in some respects. The light conditions were extremely difficult: there was lots of daylight in the dolines (sinkholes) so the dynamic between light and dark was extreme, while our headlights served as light sources in the depths of the cave. The ground was mostly wet, often slippy, and we searched for even ground to no avail. Another challenge was the humidity, but more about that later.
To light the caves, we used three 32,000 lumen LED spotlights, whose batteries could power them for approximately 15 minutes in total. We used walkie talkies to keep in contact with our yellow-clad models and carriers. Sometimes from over a kilometer away, we instructed them as to the perfect lighting and positions. We didn’t have much time; the photos had to be taken in a short window. The thick wafts of mist were typical for the time of year, but prevented us from being able to clearly see far. But it did make for mystical photos of this beautiful underworld.
I had two first-class cameras with me – the Nikon D810 and the Nikon D750. The lens I used the most, the Nikon 14-24mm f2.8, was attached to the D810. On the D750, I mostly used the 20mm f1.8 and the 25-70mm f2.8 lenses. For a few shots, I used the 70-200mm lens. The majority of shots were taken using a focal length range of 14-35mm, so I was especially glad of the 14mm.
There are people posing in many of the photos, to give a better impression of the relative sizes. My high-aperture lens allowed me to keep to relatively short lighting periods.
A stable tripod is at least as important as the camera. And with the Gitzo Traveller GT3542T and the Really Right Stuff (RRS) ball-head BH-30, I had a very good, lightweight combo on hand. The L-plate, also from RRS, was very helpful due to the lack of time and low light conditions, allowing me to quickly swap between landscape and portrait.
For both cameras, I used a remote release, as you should never touch a camera when shooting a series of photos with different exposure brackets. The filter (polarizing and neutral density) also came in handy outside the caves and in the underground jungle. It goes without saying that we had enough memory cards and batteries with us in our bags. To back up the files, I copied the images to an external hard drive (hyperdrive).Would you visit the world's largest cave in #Vietnam? This photographer did! Click To Tweet
The number of lens changes should be reduced to a minimum due to the high levels of humidity. For this reason, a second camera is really handy. There was constant dripping in the caves, so you should always keep a dry microfiber cloth within reach. By the second sinkhole, Garden of Edam, my lens was so fogged up that I could only start using it hours later.
Using a flash would be pointless due to the unbelievable scale of the cave; however, an external speed light could make for good effects if taking tent and portrait shots.
I used both cameras exclusively in manual mode. Depending on the situation and light conditions, I focussed manually but often in live view mode at 100% zoom. Although the white balance in the RAW images could be corrected after the fact, I tried to get the right light temperature on site.
It’s also important that you know your camera inside out, and that you’ve set up your menu and buttons in a way that makes sense so you can use it in the dark. The same applies to all accessories, such as tripods and remotes. When using more than one camera, the basic configurations should be the same.
Before the trip, I had both my cameras cleaned by Nikon, which was a good decision. My photos showed up hardly any annoying sensor dust, which I appreciated when I was editing them in Lightroom and Photoshop.
Interesting Facts About Son Doong
- Son Doong is in the UNESCO-recognised Phong Nha-Ke Bang National Park, Quang Binh Province.
- It is the biggest known cave in the world, renowned for its unique eco-system.
- Tours to Son Doong are restricted to 450 visitors a year.
- Less people have seen the inside of Son Doong than have stood on the summit of Mount Everest.
- In October 2014, local authorities allowed a Vietnamese company to survey the cave for building a 10km suspension cable car to transport visitors, but work was suspended following public opposition.
- Son Doong cave gets the first position in the list of 25 great new places to see in the 21st century.
- The unlit portions of the caverns are home to albino species that have adapted to life without light. In this environment, animals have no need for pigment, and many have no or diminished sight, since total lack of light makes eyes useless.
- Oxalis offering in 2016 the first time a specific photography tour to Son Doong, led by British caving experts who all have extensive experience with photo teams such as National Geographic, BBC, and recently ABC (Good Morning America). This tour has only 3 departures in 2016 (max 10 participants each).
- Good Morning America broadcast the report on May 13, 2015, to six million viewers. Millions of people have tried to book tours to see the cave after the film was broadcast.
*This article originally appeared on Cave Photography. Please click here to read the original.
Trip Realities: Why Travel Is Not Always A Paradise [Blog Inspiration]
The Traveling Photographer: A Guide to Great Travel Photography by Sandra Petrowitz [Great Reads]
Joby GorillaPod Travel Tripod [Travel Essentials]