Magazine article American Cinematographer

Ultimatte Refinements Demonstrated

Magazine article American Cinematographer

Ultimatte Refinements Demonstrated

Article excerpt

In the deserted part of a town the rain falls silently. Suddenly, lightning flashes in the night sky and the distant screech of tires is heard. At the end of the road, the famous stainless-steel DeLorean from Back to the Future whips around a corner. It careens dangerously out of control towards two people who are crossing the street. Will it be able to stop on the slick asphalt? Why don't the people run? With uncanny precision it stops an inch before hitting them. How is such precision driving possible?

It is not precision driving and this is not Back to the Future. This is the result of a two-layered video composite created to demonstrate the Ultimatte Memory Head, a portable motion control device which enables the recording and exact repetition of pan, tilt, zoom and focus moves. The deserted part of town (actually a Universal Studio back lot street) and the DeLorean comprise the background, while the people make up the foreground.

The equipment used most frequently to record camera movement is expensive, large and heavy. It is difficult to transport for outdoor shoots, and can only be run by operators who specialize in programming for motion control. Unfortunately, these experts are few in number. Productions are therefore often prevented from using motion-controlled special effects.

The Ultimatte Memory Head was developed to allow quick and easy execution of motion-controlled camera movements. Composed of only three pieces, each weighing no more than 30 pounds, it can be packed, transported and unpacked rapidly. Programming is accomplished with a 32-key pad which operates much like a calculator.

Using the Memory Head to record pan, tilt, zoom and focus, the background described above was shot first so that the unpredictable car could be followed. This resulted in a videotape of the shot and a diskette of the Memory Head motor positions. Shooting the foreground element was the next step. Ordinarily, subjects would have to be put in a blue screen set and the Memory Head moves repeated. In this case, a set 25' X 15' with a floor space of 375 square feet would have been necessary. Not an impossible requirement, but there is an easier way.

Blue screen stages can be rented and this is the easiest thing to do, especially if there are a full selection of lights, rigging and grips available. If economics dictate the construction of a set, the most difficult part will be the coving. Sharp corners are to be avoided as they will look like vertical and horizontal lines in the composite. It is recommended to smooth the corners to form a cove, especially between the wall and the floor. Plaster is often used, but expert application is necessary because the blending into the walls and floors must be perfect.

Low-cost linoleum available in rolls 12feet wide is useful as a type of prefabricated, easy-to-assemble, go-anywhere set. The non-patterned backside accepts blue or green paint without cracking or peeling. It is also flexible enough to bend into a coving between the floor and the wall. But no matter how quick or easy the construction method is, the smallest area possible is recommended.

In order to get optimum matting benefits with an Ultimatte device all areas must be uniformly lit. This is difficult when all the surfaces are not on the same plane. Realism in a composite is enhanced by foreground/background interaction usually accomplished with blue set-pieces that duplicate an object in the background. In the demonstration, a set-piece, intended to be the DeLorean at rest, enabled the actors to interact with the car on the background tape. This plywood facsimile of the frontend of the car was sanded smoothly and painted blue. It introduced its own set of lighting problems.

In almost every matting situation, set-pieces, like the plywood car, will be added to a set. When set-piece surfaces are combined with those of the walls and floor, chances of over or under-lighting an area increase. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.