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Record sound and video for the Web

Here are some introductory audio and video recording tips.

By Joseph T. Sinclair

Audio recording tips

Your computer is a capable digital-sound recording device. Buying any other sound recorder is expensive and unnecessary unless you need portability. With an audio editing program as your recorder and a good sound card like Sound Blaster Live, you have the beginnings of a streaming media production studio.

The two primary considerations when recording audio are creating distortion-free sound and eliminating background noise. Modern recording equipment, even inexpensive equipment, makes high-quality recording easier than ever.

With digital sound, unlike analog sound, any distortion is lethal. Consequently, when recording sound for digital use, you need to lower the range for the headroom. Headroom is the portion of the decibel range that starts where the sound begins to distort and ends at the point where the distortion becomes a distraction to listeners.

In an analog recording, headroom typically covers the range from 0 dB (decibels) to +10 dB. The loudest part of the signal should register in this range on a VU (volume unit) meter. With digital recording, you need to use your equipment so that the loudest part of your signal registers between -10 dB and 0 dB on the VU meter. Recording with a digital recorder usually results in much a lower level of background noise than recording with an analog recorder.

Eliminating background noise is an ongoing battle in recording quality audio. One common cause of noise is faulty cables and connections. Refer to your owner's manuals to make sure that the connectors you use match those required by your equipment from beginning (microphone) to end (computer sound card). Using an adapter at any connection point may cause background noise. Use high-quality cables that are balanced or shielded. Replace your $4 cables from Radio Shack with $15 cables from a professional supplier like Markertek.

For more information on audio production, read Craig Anderton's Home Recording for Musicians, by Craig Anderton.

Video recording tips

For most Web surfers, streaming video runs closer to 4 fps (frames per second) than it does to the 30 fps of television. To compensate for this difference, minimize the movement in your video content as much as possible. The more your content changes inside a frame, the slower the frame rate and the lower the quality of the image.

As a result of this problem, panning and zooming don't work well in streaming video because in both types of movement, everything inside the frame changes at once. If you must pan or zoom, do it very slowly. Restricting movement to just one area inside the frame works best. For instance, a close-up of a person talking at a lectern plays back better than a close-up of a person playing basketball. In the lectern shot, all that moves is the person's facial expressions and lips, and occasionally his or her head—in other words, a small portion of the entire frame content. In the basketball shot, the player's whole body is in constant movement, which causes change in a large portion of the frame. Stay aware of your subject's movement when you shoot a video scene, and always use a tripod to keep camera motion to a minimum.

Video also has background noise: small specks and flickers that appear briefly in the background. The best way to eliminate video noise is to use S-Video (or digital) cables and connectors instead of the composite cables and connectors intended for consumer use.

For a wealth of information on video production, read The Videomaker Handbook, published by Focal Press in 1996.

Joseph T. Sinclair developed the first gourmet food store on the Web in 1994 using Web database technology. He has written seven books about the Web.

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