How do high-definition, slow-motion cameras work?

How do high-definition, slow-motion cameras work?

In entertainment, an awful lot of stuff happens behind closed doors, from canceling TV shows to organizing music festival lineups. While the public sees the end product on TVs, movie screens, or radio dials, they don’t see what it took to get there. In Expert Witness, The A.V. Club talks to industry insiders about the actual business of entertainment in hopes of shedding some light on how the pop-culture sausage gets made.

Even before The Matrix showed the world “bullet time,” movies used slow motion to turn chaotic shots into things of beauty. But with advances in technology, directors can now shoot things that were once too fast for film with as much clarity as a slow moving object. High-speed, high-definition camera work is more common on both big and small screens.

Rick Robinson is the division vice president of Vision Research, the company behind the Phantom HD High Speed Camera. A Phantom can shoot in high definition in up to 1,455 frames per second (film is usually shown in 24 frames per second), and have been used in television and movies for years to film high-speed subjects. One of the most recognizable uses of the camera comes from Sherlock Holmes: Game Of Shadows, when a bullet pierces a tree. The A.V. Club spoke to Rick to find out how the cameras work, what other applications they have, and where they’re showing up next.

The A.V. Club: Can you give a layman’s explanation of how the Phantom high-speed camera works?

Rick Robinson: One way to think about the camera is like a digital still camera. It takes a still image, like most digital cameras do these days, every time it’s clocked. So, it’s taking still images at rates from a few dozen to a few hundred to a few thousand to a few hundred thousand pictures—individual frames—per second. I think the best way to think about that is to go back to what the projection speed is on a television—30 frames per second, or at a movie theater—24 frames per second. If you take pictures at 24 per second and play them at 24 per second, you’re going to see normal motion. But if you take pictures faster than that, say, if you take pictures at a thousand times per second, and then you play it back at 24 frames per second, you’re going to see a slow-down in the action that is the ratio of those numbers. It just takes a lot of still frames per second.

AVC: Aside from movies, what are the typical applications for these types of cameras?

RR: Even bigger than movies over the past six or seven years has been television content, primarily commercials. I know a lot of commercials for cars, or commercials for shampoo, or food commercials will use slow motion. That has been huge, because people were motivated to buy high-definition televisions, and the whole industry was moving to high-definition resolutions, but there really wasn’t that much high-definition content. So there was this tremendous thirst for content in HD, starting back in 2004 and 2005. 2006 is really where it started to become huge. That demand for high-definition content created a growth spurt for companies that were making high-definition cameras, so that there was a sufficient capacity of cameras on the market to shoot the content that people needed for television. Commercials are one thing, documentary content is another, and then science programs are another. There was a program for a while called Time Warp, and the other programs that try to prove or disprove certain beliefs. They’ll use the slow-motion cameras as a part of it. Television is even bigger than motion pictures, although the Phantom cameras have been used to make, primarily, slow-motion visual effects for a fairly large number of films over the years.

AVC: So when someone from television or Hollywood wants to buy a camera from you, typically his or her purpose is to film something moving very fast and slow it down for the viewer?

RR: Certainly something moving very fast is a target for slow motion, because you’re used to seeing it with the naked eye at normal speed, and it looks a certain way, and you make assumptions about what’s happening. Sometimes when you film it with a high-speed camera, and you watch it back in slow motion, you see things, phenomena, effects that you would not normally see with the naked eye. But we also see the cameras in the motion picture and television industry used to take pictures of things that might not be a high-speed event. A model flipping her hair, for example, or water coming out of a shower faucet, or a car flying by. You don’t typically think of those as high-speed events like a bullet or explosion. But even those common, ordinary events that you might not think of as high speed, when filmed with a high speed camera and played back in slow motion take on a whole new beauty.

AVC: Could you walk through how your camera can follow a bullet, like in Sherlock Holmes: Game Of Shadows?

RR: Very often you see the slow-motion cameras taking shots where the camera is not moving. The reason is that if you have a very high-speed event, like a bullet or explosion, we may shoot for one second. That’s all you need, and when you play that back, that might expand into six seconds, or 10 seconds, or 12 seconds. It’s obviously going to take a lot longer to play it back than it is to film it. So for a long time, because you were shooting for such a short period of time, the cameras were often mounted static. However, recently, either through the use of a high-speed dolly or through the use of a robotic arm on which the camera is mounted, we’re seeing more and more people actually move the camera to track an object, or move the camera to change its viewing angle or its view of the object as it’s moving. Even if the original shot still only takes one or two seconds, the camera is being moved very fast during those one or two seconds, but because it plays back in slow motion, it doesn’t appear to be moving fast. You have an extra dynamic element to the result, because not only do you have the subject that you filmed, you have the angle at which the camera is viewing the subject moving in slow motion. My understanding on the Sherlock Holmes shot is that they used a high-speed dolly, and that was how they moved the camera through the forest during some of those shots.

AVC: Are there any forthcoming projects using your camera that you’re particularly excited about?

RR: There are a number of different movies being made with the camera that build on the many movies that have been made. One that I know of that I’m particularly looking forward to doesn’t have a title yet. It’s a movie that was written, produced, and directed by Michael Mann, so its working title is something like “The Untitled Mann Project” [The movie’s current working title is Cyber. —ed.]. It stars Chris Hemsworth and Viola Davis, and it’s something about high-level computer hacking and cyber-crime. It just finished production, and is headed into post-production. It was shot with a couple of Phantom cameras, and my understanding is that they were used quite a bit.

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