Custom-Built Camera System Delivers High Quality with a Low Profile for the Tale of an Alien Seductress

Under the Skin, a science-fiction arthouse film that just crossed the $1 million mark at the U.S. box-office, is being sold as a spooky erotic thriller featuring Scarlett Johansson as a sexy alien invader on the loose in Scotland. That's fair enough. Directed by English filmmaker Jonathan Glazer (Birth, Sexy Beast), it's one of the more unsettling films in recent memory, combining an enigmatic story line (Johansson's character is seducing men and then taking them prisoner for unexplained but clearly unsavory reasons) and genuinely weird imagery (her victims sink into a glassy black floor, then wake up suspended in blue fluid) with incongruously ordinary footage of the city streets where the main character picks up unsuspecting Glaswegians in a nondescript van.

It turns out that Johansson's encounters with ordinary Scots feel realistic because they are real. Those city scenes were captured with tiny, inobtrusive cameras. Many of the people who appear on screen, including some of the men who chat up Johansson's character, aren't actors at all and don't see the cameras. "Scarlett's character was interacting with real people who were completely unaware that they were in a fictional film," said producer James Wilson in an interview released by distributor A24Films. (Permissions were secured after the fact, of course.)

You might wonder what cameras the production used to accomplish that — tiny GoPro cameras, perhaps? Or surveillance cams from one of the big manufacturers like Sony or Panasonic? Well, the footage had to intercut seamlessly with the production's main ARRI Alexa cameras, which were shooting ARRIRAW, so quality was paramount. It turns out Under the Skin used the One-cam, a new modular system developed by London studio One Of Us specifically for Glazer's use on the film. "We were shooting half an hour unbroken takes of improvised dialogue with eight cameras simultaneously, which is like a feature's worth of photography," says VFX supervisor (and One Of Us co-founder) Tom Debenham in the video below. "We had to build a whole ecosystem that was basically all the components of a camera that could either be stuck together or separated and used in a number of different modular ways."

Glazer told The Dissolve that 10 of the One-cam systems were built, allowing multiple cameras to be placed in strategic locations for different scenes — embedded in a dashboard, mounted on a motorcycle, or hidden somewhere on the street. Eight cameras were hidden inside the van Johansson drives around Glasgow, allowing the production to catch spontaneous performances by non-actors in what cinematographer Daniel Landin described in an Indiewire interview as "a fairly seedy area." They didn't realize they were being chatted up by a movie star. "[The One-cam] is about the size of a household box of matches [and] you could fit 16mm lenses on it," Landin told Indiewire. "The image we generated we ended up liking so much we would have shot the entire film on that camera if we could have made it rugged enough to withstand all kinds of weather."

Glazer was impressed enough by the One-cam's performance that he gave One Of Us a testimonial: "Digital is too sharp and illustrative. There's no immersion, no fall-off, no rolling off into black or color bleed. No accident. No alchemy. One-cam is the opposite. It seems almost chemical in how it photographs the image. For a digital camera, it has unprecedented texture and depth. It sees how my eyes see."

The camera head weighs just 333 grams, or about 12 ounces, and can be tethered at a distance of up to 100 feet from the recording unit, which the company says is roughly the size of a 16mm camera body. The camera is rated at 500 ASA with a dynamic range of at least 9 stops in daylight. The Super 16 (one-inch diagonal) image sensor is a global shutter CCD, and the camera's output is uncompressed 12-bit raw at a resolution of 2336×1752, recorded to SSD mags. One Of Us developed custom dailies tools to convert to Cineon-log DPX files or DNG and the signal can be monitored over HDMI or HD-SDI.

Glazer rode around in the back of the van, where the camera data was being recorded and where monitors were set up to show the output of all eight One-cam units. According to dailies provider Mission Digital, when the eight van-mounted cameras were all shooting footage, the production generated six TB of footage in a day.

One Of Us handled VFX for the film, which was then finished at color-grading studio Dirty Looks, which is located in the same building. Custom color science was developed to bring the footage from the One-cam and the Alexa together in the editing room and to match look and feel in the Filmlight Baselight color-grading system. VFX were conformed as they progressed and integrated into the 2K grading environment. "Combining technical resources allowed a quick turnaround between creative departments and helped us deliver what this film needed," said Dirty Looks' Tom Balkwill in a prepared statement.

Colorist John Claude noted that Glazer wanted a very naturalistic look for the street scenes, but the film veered toward stylization in less conventional segments. "The blue 'swimmer' sequences, when one of Scarlett's victims is under the pit, were quite challenging but made easier with Baselight's matte-layer stack management," he said in a statement.

Balkwill described another scene, a golden-colored montage that incorporated 93 blended 2K layers as Johansson's face becomes visible in the middle of the screen, and gave the Baselight a shout-out for its ability to handle that kind of complexity. "This sequence could only be finished with Baselight," he said, "because each individual layer needed its own tweaks in stabilizing and grading."

The resulting film is challenging and unusual, employing considerable technical innovation to support a formidable visual imagination. It's in limited release in the U.S. and rolls out to more theaters this weekend.