|
In analog systems, the video signal from the camera is delivered to the video in connector(s) of a VCR, where it is recorded on magnetic videotape. A camcorder combines both camera and tape recorder on a single device. One or two channels of sound may also be recorded on the videotape (mono or stereo). The video signal is written to tape by a spinning recording head that changes the local magnetic properties of the tape's surface in a series of long diagonal stripes.
Because the head is canted or tilted at a slight angle compared with the path of the tape, it follows a helical (spiral) path, which is called Helical scan recording. Each stripe represents information for one field of a video frame. A single video frame is made up of two fields that are interlaced.
Audio is recorded on a separate straight-line track at the top of the videotape, although with some recording systems (notably for 3/4-inch tape and for 3/2-inch tape with high-fidelity audio), sound is recorded helically between the video tracks.
At the bottom of the tape is a control track containing the pulses used to regulate speed. Tracking is fine adjustment of the tape so that the tracks are properly aligned as the tape moves across the playback head. This is how your VCR works when you rent singing in the Rain (on video tape) for the weekend. DVDs do this quite differently.
Shooting Platform
Never underestimate the value of a steady shooting platform. A classic symbol of amateur home movies is shaky camera work. Using a tripod or even placing the camera on a stable platform, such as a rolled- up sweater on the hood of a car, can improve a shot. With a little care, and careful adjustment of the lockdown screws, a sturdy conventional tripod can do wonders.
If you must shoot handheld, try to use a camera with an electronic image stabilization feature for static shots a "steady- cam" balancing attachment, or use camera moves and a moving subject to mask your lack of steadiness. Even using a rolling office chair and sitting facing the back with the camera balanced on the chair-back makes a convenient, stable dolly.
Taking care of your tapes:
- Always fast- forward new tapes to the end and then rewind them, a technique known as "packing" to make sure that tape tension is even from beginning to end. Unequal tape tension can cause timing and editing problems.
- Black- stripes your analog tape by running it through the recorder once with the lens cap on and without audio input. This way only black and a uniform control track is recorded. Later, during editing, blank spots in your video program will be a quite black instead of snowy noise. Also, try to put time- code on your tapes or video signal as it is input into whatever you are using to record your action. This will greatly aid you in choosing edit points later on, when you are combining video cuts on a nonlinear editing system.
- Before you being editing, always remove the break- off tab on the back of your original video cassettes, in order to avoid accidental erasure or overwriting. Editing videotape on a tape-to-tape editor requires a lot of shuttling backward and forward and this can deform the tape.
- For best results, do not reuses 8mm video cassettes If you have nonlinear editing (NLE) software on your computer, digitize the shots you plan to use in your final product and then edit the digital footage. NLE allows you to piece together your final product from video, image, and audio elements stored in various files on your computer.
|
Participants