Tech Talk

by Joe McCleskey
October 1997

What effect will the introduction of high-definition television (HDTV) have upon the value of current models of camcorders? And once it’s here, how will we cable our existing analog gear to the newer digital television sets?

Edward Rotherham
Pittsburgh, Pennsylvania

Good question. Although it’s impossible to say what kind of audio and video connectors the manufacturers might come up with in the next few years, chances are they’ll stick with the tried-and-true RCA-style composite video, RF cable and S-video connectors for a while yet. Currently, the whole question is wide open as to how the new digital broadcast industry will take shape, but one thing has been agreed upon by most of the TV manufacturers: the first wave of HDTV sets will be compatible with existing analog broadcasts. We can assume that they will probably take the same attitude with regard to standard audio and video connectors. Also, they’ll make converter boxes available that will change the incoming HDTV signal to one your ordinary TV can use.

I’ve noticed in your camera reviews that there are always two numbers given for horizontal resolution--one for the camera, and one for playback. Furthermore, I’ve noticed that camera horizontal resolution almost always exceeds the playback horizontal resolution by a significant amount. Why is this? Is there any way to determine these numbers before purchasing a new camera?

Charles Ormsby
Madison, Connecticut

The resolution that a given camcorder is capable of producing is chiefly dependent on two separate systems: the camera section, which includes the light-gathering CCD, and the recording system, which lays the video and audio signals down onto the tape as a continually varying voltage. The process of recording a video signal onto tape always involves at least a small loss of signal, as the laws of thermodynamics clearly tell us. Higher-quality recording systems, however, are capable of making a cleaner transfer--which is why we bother to report the playback resolution numbers in our reviews.

To check out how well a certain camcorder’s recording system will perform before you buy, ask the dealer if you can put in a tape and shoot some video. You’ll have to use your eye to tell you how much difference you see between the signal coming from the camera and the signal coming off tape.

Note that digital video and audio signals are much easier to record than analog signals. This is why you’ll often see an identical number published for camera and playback resolution for a digital camcorder.

I recently decided to look into purchasing a computer for nonlinear editing. After much research and numerous phone calls to computer companies, I was convinced that I was thoroughly prepared to purchase my nonlinear machine. The only thing that was questionable to me was the type of hard drive to use for video capture. Some said a SCSI drive was required, and others said that an enhanced IDE drive would suffice. Since I’m going to spend thousands of dollars on this system, I want to be sure not to make a mistake.

Is SCSI necessary? Or is enhanced IDE good enough?

Robert K. Cary
Prescott, Arizona

In past years, Videomaker has stood firm on the conviction that if you want high-quality nonlinear video, you should go with a SCSI drive--more specifically, a fast and wide SCSI-2 drive that’s optimized for video capture. Recently, however, enhanced IDE drives (sometimes referred to as Fast ATA-2 drives) have made impressive strides, almost (but not quite) catching up with SCSI in performance. Since enhanced IDE drives are less expensive and easier to configure than SCSI hardware, many nonlinear videographers are choosing enhanced IDE for their capture hardware.

Even so, the quality of the video you’ll achieve with a fast and wide SCSI-2 drive will still be superior to that of an enhanced IDE configuration. Bottom line: if you want quality that’s good enough for home production, enhanced IDE should work well for you. If you want professional-quality video, stick with SCSI (as the pros still do).

In your December 1996 issue (page 93), Scott Anderson mentions "digital post-production stabilizers." I’ve never heard of these, nor have any of the video stores I’ve contacted. Please fill me in! I’ve got some old footage shot on a windy day that I’d love to de-shake.

Doug Smith
Scarsdale, New York

The Production Bundle version of After Effects, a popular special-effects program produced by Adobe, comes with many useful sub-systems for manipulating video images. Among them is Motion Stabilizer, a software-based system that steadies shaky camera movement. The software is expensive ($1995), but it’s also very popular, so you might be able to find a local post-production facility that will do the work for you for a reasonable price.

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