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Hack 36. Freeze Time
Roll your own "bullet time," a la The Matrix.
Some time ago, I
3.12.1. Discovering the Past
I'm quite amused by this whole concept and method, since it has been
Lore has it that the rig was set up to
18.104.22.168. Designing the first solution
According to an article in Videomaker magazine (June 2001; "Magic Morphing" by Scott Anderson), the first example of bullet time was in 1980 by an art student named Tim Macmillian. He was busy making collages of photos taken at several angles, usually random, at the same instant. As he progressed to adding more and more cameras per shot, he got to a point where he wanted more cameras than he could afford, so he built one to suit his special need.
This camera was just a big, long piece of wood with a slot, a window, a strip of film, and a shutter with lots of individual round holes. By tripping the shutter, the entire strip of film would be exposed through the holes. The result: when quickly flipping through the images, the action remained frozen, but it would appear that a single camera was in motion rather than several cameras sitting still.
22.214.171.124. Using hardware and software
Fast-forward several years and along comes
and special effects guru John Gaeta, to refine this effect to new levels. For
Gaeta pioneered the concept of computer-controlled still cameras that shot a fraction of a second after one another to create both a camera sweep and a slow progression of time rather than a frozen moment. He also made
So, what exactly is this effect called? Tim Macmillan called it
Manes Studios (a.k.a.
guys) called it
but Gaeta called it
The effect is also called
timetrack, virtual camera, multicam,
3.12.2. Approximating the Effect
Here's how you can approximate this effect with some
126.96.36.199. Setting up for the shoot
For the shoot, you should collect six video cameras and set pair of them at the 90-degree points. If all else fails, you'll at least have good video from these two angles. Between the two cameras, fill out the arc with the other four cameras.
You should place a light stand at the focal point of the arc. This will be your target point. Then use a string, with a bubble level on it, to measure out a common distance and height for the front/center for all of the camera lenses. The measurement will ensure that all of your cameras are the same distance and height from the target point. Figures 3-28 and 3-29 show the initial setup.
To calibrate pan, tilt, and focal length, you need to connect the first camera to a video monitor [Hack #11] and aim it at the light stand. Then mark the screen position of the target point on the tripod directly onto the monitor with a dry-erase marker.
Finally, connect each of the remaining cameras, in turn, to the same monitor and adjust them to position the target point directly behind the marker spots on the monitor glass. Figure 3-30 shows a cameraman adjusting one camera while using an external monitor for reference.
You should do your best to eyeball the entirety of the scene, with the expectation that any necessary corrections can be done in post-production.
Figure 3-28. Placing the main cameras on the outside of the arc
Figure 3-29. Measuring the distance to each camera, an important step
188.8.131.52. Capturing the scene
With all the cameras running, either slate your shot [Hack #9] or fire an still-camera flash just prior to each event, in order to mark the same instant in time on all the tapes. From this marker, it will be easy to identify the starting frame on all cameras. You should then be able to step forward to a frame during the event while editing, and jump to the same event instantly on any camera.
184.108.40.206. Finishing the scene
You can finish the shot using practically any video editing application. You should use a paint tool, or other frame of reference, to capture the synchronized still frame needed from each camera. From there, you can use the timeline to make a template that properly aligns and matches-up the six cameras. The template can then be used to create as many different shots as you want.
Figure 3-30. Adjusting a camera using an external monitor
You can see how the effect turns out at http://www.hiddenphantom.com/NBBF/PalmHeel.wmv (Windows Media Player 9 or higher, or VLC, required).
— Nick Jushchyshyn
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