by Stephanie Argy
Unit photography by Cos Aelenei
Additional photos by Ross Emery, ACS and Paul Heinerth
Photos courtesy of Screen Gems, Ross Emery and Karst Productions

When director of photography Ross Emery, ACS read the script for The Cave, a horror movie set in a system of underground caves, he knew it was the most difficult project he’d ever been offered. Most of the story takes place in an environment with no light whatsoever, and lengthy sequences unfold in cavernous underwater spaces.

The movie tells of a team of professional cave explorers who are trapped underground while searching for several people who disappeared while investigating a cave system under an old church in Romania. The team soon discovers that the cave is inhabited by unusual life forms that thrive in the closed-loop ecosystem that has evolved underground. Some of the organisms begin threatening the explorers, who speculate that the life forms are trying to take up residence inside them as parasites in order to learn how to survive above ground.

In collaboration with underwater director of photography Wes C. Skiles and his team of divers, Emery and director Bruce Hunt decided to shoot all of the picture’s land-based scenes on 35mm, and all of the underwater sequences on high-definition (HD) video using a Sony HDC-F950 with 4:4:4 chroma sampling. The plan was to shoot some of the underwater scenes practically in a real cave system in Mexico and the rest in tanks on stage in Romania.

The first three months of the shoot took place at Media Pro Studios in Romania on sets both wet and dry, including a complete underwater cave system with a variety of caverns. This was followed by six weeks of second-unit photography in caves at Hidden Worlds, Cenote Park, in Mexico’s Yucatán peninsula. Hidden Worlds was discovered in the late 1980s, when a limestone-mining operation working in the jungle kept losing equipment because it was sinking into holes. Explorers went below the surface and found a vast cave system, for which they have so far mapped 40 entrances and 200,000' of linear passages, including some huge, spectacular caverns that are featured in the movie.

Among those explorers was Skiles. “One of my great pleasures is to explore and map underwater caves,” says Skiles. “I go on expeditions, find new caves, and explore them to find out where that water is coming from.” Skiles also has made numerous documentaries, often using his own Sony HDW-F900 cameras. Hunt, Emery and the producers of The Cave were intrigued by the idea of shooting the underwater sequences in HD, but they wanted to see tests, so Skiles and Anthony S. Lenzo, the underwater technician and second underwater camera operator on The Cave, put together a side-by-side comparison of footage shot with an Arri 35-3, a Sony HDW-900/3 and a Sony HDC-F950 4:4:4 camera.

The HDC-F950 records onto a separate deck in the HDCam SR format, and, unlike the HDW-F900, which uses 4:2:2 color sampling (meaning that for every four times it samples the luminance of an image, it only samples the color twice), the HDC-F950 samples color as frequently as luminance. Moreover, whereas the compression of the HDW-F900 makes its effective resolution only 1440x880, the HDC-F950 delivers a true 1920x1080 image. But the test results were even more startling than the specs might suggest. “The F950 and film images were pretty much a tie, and the F900 footage was inferior, especially when taken to the interpositive and internegative stage,” says Emery. “The advantages of no reloads and real-time viewing of images made the F950 the way to go.”

The next puzzle was how to light the cave environments. “Those who explore caves know this is the darkest environment you can know,” says Skiles. “Imagine putting your face in a bowl of chocolate pudding, then opening your eyes. The movie’s sense of mystery had to come from that — we’re seeing the first light that has penetrated this world.” For his part, Emery considered the darkness an additional character in the movie. “I think darkness is scary to everybody,” says the cinematographer. “Our early discussions were about how dark we could take the film, how we could reveal clues.” He found some references for the underwater light levels in Skiles’ documentaries. “We took what he’d done and applied it to drama, trying to see a little less than we’d see in a documentary. Our focus was more the characters than the spectacular caves.”

Emery knew that once the actors entered the cave system, they had to carry all of the sources of illumination. “This is essentially a movie lit by the actors,” he says. During prep, the cinematographer did extensive research on portable light sources, including LED flashlights, Xenon flashlights and HID flashlights, which are used by divers. “At one point, I probably knew more about flashlights than anyone else.” Through testing, Emery determined that Dive Rite H10-HID lights were a good solution, and he combined those with Xenon and LED units.

The actors — and the divers doubling them for the underwater sequences — all had to learn how to light their environments. Skiles recalls, “I told the stunt divers, ‘This is the reveal, this is the emotional high point, you need to rake the light like this.’” As the characters’ situation becomes dire, their light sources gradually disappear. When the explorers first enter the caves, they have a lot of light sources, many of them carried on a large sled. (The sled was based on one that Skiles helped designed in 1988 to carry food, camping gear and cylinders into an underground river that runs below the Nullabor Desert in Australia.) But gradually, their lights fail or are destroyed or lost. “That was a progression I was keen to build into the story,” says Emery.

Emery also wanted to make sure that the look within the caves evolved over the course of the picture. The cave systems already offered a variety of terrain that helped suggest the progression of the story — the characters pass through wet caves, underwater caves, underground rivers, ice caves, cliffs, and, finally, a cave lit by the characters’ ignition of methane vents (part of their effort to foil the light-sensitive creatures pursuing them). But as the explorers’ feelings about the cave change from curiosity to fear, Emery alters his compositions, going with tighter lenses and more cramped framing. As divisions in the group become greater, some characters are framed differently to emphasize their more difficult circumstances. Emery also used a timing shift box to deregister the shutter and movement of the camera, with tilt-shift lenses to skew the image of Jack (Cole Hauser) as the infection he contracts in the cave starts to overtake his system.