Motion picture cameras take numerous forms, but they all do about the same thing. Cameras are mostly made of precision metal parts that are built to last. A few of them have plastic rollers. Look inside the CP16 here and you can see a lot of little nylon wheels. Nylon is very hard and resists scratches and dents. In this way the rollers stay smooth and will not damage the film that passes over them.
One of the main ways polymers help in film cameras is to make them quiet. Cameras used to shoot sound film can't make much noise or else the movies you watch would have camera noise in the background of every scene. Along with smooth motion and quiet motors, these cameras have thick metal casing. Sometimes the intereior of the camera has a polyurethane foam layer with a vinyl covering, like the one on the door of this CP16. Cloth padding inside the camera also protects film from scratching on the camera interior.
Another way that sound is kept in is by encasing the entire lens in a polethylene and aluminum housing or "blimp" like in this Arriflex BL 16 camera. The lens controls are on the outside and the lense settings are visible through little Plexiglass windows on the housing. This casing and a layer of air netween it and the lens keep sound from exiting the camera through the lens. I thick piece of "sound glass" placed over the front of the lense housing also helps. In such cameras the clear sound glass can be changed out with a piece that is coated with appropriate filter material to filter light as well as sound.
Another surprising use of polymers in the CP16 camera is the rubber band that is hooked from the drive system of the camera to the takeup reel on the magazine. The rubber band must be pulled around the takeup reel every time the camera is loaded. It seems almost too simple to work, but it does!
OK, so we've got the camera loaded and we're ready to go... ACTION!!! Wait! Not yet. There are still a few other things we need to shoot this movie. Cameras and sound equipment need all sorts of accessories that make them work right. For instance sound cables unsed to hook up the tape deck to the microphones and to the camera for synchronization.
And don't forget power cables. All of these electrical wires are pretty delicate, and must bend without breaking. And since they all carry some kind of electrical charge, they also have to be insulated from objects and people on the film set. The best way is with plastic insulation and rubber casings, which allow then to bend, but also help reduce stress on the wires. This is most important at the base of the wires where they are hooked to the equipment. Often the rubber in these places is reinforced with extra layers in addition to sturdy metal collars, connectors, and springs.
Another thing that we need to shoot films is rechargeable batteries. They come in all shapes and sizes, but the one thing they have in common is some kind of casing. The cases are either plastic - like these cartridge type batteries whcih are covered in polyethylene, or vynil like this Arriflex battery belt. The belt is desigend so that it can be unzipped for easy replacement of the batteries when they are worn out.
Slate: Scene 1, Take 1 [CLAP!]
Before we can start shooting this film we have to slate it. You know, that neato thing that they clap at the beginning of each scene. The clapboard at the top of it is made of wood, which is a naturally occuring polymer, and the board is made of tough slick poly(methyl methacrylate) (Plexiglass again), which makes it possible for us to write the scene number and the take and other descriptive information with an erasable marker.
So if it's made of plastic, why do they call it a slate? Well, they used to be made like a slate, the little blackboard that kids used in school about a million years ago. Instead of erasable markers filmmakers used chalk to mark the scene numbers.
So why do we slate anyway? Well, apart from the fact tthat it makes a neat sound and makes a film shoot seem more like a film shoot, it also helps us match the film to its soundtrack. The assistant says the scene nunmbers so that they are recorded on the soundtrack and the slate shows it on the film. But just as important it helps to synchronize the picture and the sound. The CLAP! is a reference point on the tape and is matched with the exact frame of film where the clapboard hits. So without our polymer slates we would have a pretty difficult time of it.
Special thanks to the University of Southern Mississippi Department of Radio, Television, and Film for the opportunity to get all the pictures on these pages and to Gregory Brust for aiding in the idetification of all these polymers.