Getting to Know Digital Camcorders - dummies

By Keith Underdahl

Before venturing into the world of digital video, you need to know the difference between analog and digital signals and how they relate to video. Analog refers to changing the original signal acquired (in a camera) into something that represents the signal — in this case, into a wave form.

The term digital video means a couple of things. It can refer to video that is shot by a digital camcorder, and it can refer to video that is captured (digitized) on a computer.

The quality and glamour of digital video is that it can begin and remain digital from camcorder to computer. You accomplish this thanks to a standardized wiring connection, or cable, used between the camcorder and a special card (board) on your computer. This cable and its connections, known by three names — IEEE 1394, i-link, and Firewire — are some of the most significant factors in the development of the digital video industry because they keep digital video digital. Without an IEEE 1394 connection, the video signal would be degraded into another format, such as VHS or S-VHS.

The IEEE 1394 connection is the lifeline of the digital video enthusiast. Because of it, you are able to maintain the digital resolution and audio quality of your video throughout shooting and editing and up to the distribution of your product.

Digital video formats

All digital formats have some common traits. For one thing, digital video formats use binary code (signals that are made of series of ones and zeros). The least expensive to the most expensive digital video formats share the enviable capability of unlimited generations (of editing) without a decline in quality.

Analog signals corrupt as you transmit the signal from the camera to the recorder and on to another recorder (editing). This isn’t so with digital video. In many ways, digital video recorded to tape is like a word-processor file. No matter how many copies (generations) are created, the files either work or they don’t work. There’s no in-between. Also, digital video can be converted to analog video. Last, and perhaps most important, all the digital formats have excellent resolution quality.

Resolution quality is the degree of sharpness of an image as measured by the number of pixels (picture elements) across and down on a display screen.

MiniDV format

MiniDV is the “low-cost” brother of the digital formats. Even so, it goes toe to toe with Betacam SP, the video industry standard. The resolution quality of MiniDV and Betacam SP are perceptively similar. But the audio signal of MiniDV is actually better than Betacam SP’s. And, as just mentioned, the multi-generation tape-to-tape quality of MiniDV is better than Betacam SP’s. MiniDV has some limitations, which I discuss throughout this book. But, compared dollar for dollar with Betacam SP, MiniDV is a technological wonder.

Digital S, DVCPRO, and DVCAM formats

The top three commercial digital formats are offered by JVC, Panasonic, and Sony, respectively. Even though they are all digital, they are not compatible. The comparative value of one over the other is a matter of personal preference. As a matter of fact, if you were to put 20 producers in a room to decide which of the digital formats is best, you’d better make sure they first leave their guns, knives, and tripod handles at the door. In any event, one significant difference among the three is that DVCAM equipment accepts video tapes with a MiniDV format.

The three commercial digital formats share a digital output standard called Serial Digital Interface (SDI). This format is the way digital-format recorders transmit their digital video to other digital equipment, such as other digital recorders or computers. SDI and MiniDV’s IEEE 1394 are distinctly different technologies for accomplishing approximately the same thing.

Selecting your camcorder

Based on your budget, you’ll have to determine how far you can go in buying equipment. If necessary, you can buy the basics now and supplement with the niceties later. When choosing a high-quality digital camcorder, keep these things in mind:

  • Lens quality: Size counts when it comes to a lens. The larger the lens, the greater the degree of light and image collection quality. Good cameras have interchangeable lenses. And, customarily, a professional lens exceeds the image quality of the recording medium. Believe me, manufacturers will let you know when their lens achieves these criteria.
  • Pixels: The term pixels is an abbreviation for pixel elements, or the number of dots that together comprise a picture. Basically, the more pixels in an image of a fixed size, the greater the resolution quality of that image. Some good cameras offer as much as 410,000 or more pixels per CCD (or equivalent).
  • CCDs: The size and number of charged couple devices (CCDs) affects the quality of the recorded image. A high-quality digital video camera has three CCD chips. One-third inch CCDs are considered a good minimum. In video, a camera acquires light and color on chips called Charge-Coupled Devices, or CCDs. These CCds collect visual images and convert them into either an analog signal (waves with varying amplitudes) or a digital signal (a series of ones and zeros).
  • Audio options: A high-quality camcorder should be able to record audio using XLR balanced-type microphones. This allows professional quality recording.
  • Time code: A high-quality camcorder should be able to record time code. Time code is necessary for frame-accurate editing. Frame accuracy is essential for videotape control in identifying clips and for editing.
  • IEEE 1394 interface: The camcorder needs a digital video in and out connection. The in and out connection is how you send out and receive back video in a digital format. IEEE 1394 is a standard that ensures compatibility among digital video equipment.
  • Special features: Features will vary from one camcorder to the next, but some features are vital. The camcorder should be able to record in fully automatic, semiautomatic, and fully manual modes. Also, the camcorder should offer 16:9 aspect ratio for future video use. And the camcorder should offer the zebra function and the optical image stabilizer.