Going Digital

Great video quality aside, the true coup de grace to the high-end video production world is that today's top prosumer camcorders are digital. This may be yesterday's news to some of you, but for those of you just getting your feet wet in the video production world, listen up. Digital video (DV) changes everything.

In the old days (a couple years ago) analog was it. DV was ridiculously expensive and definitely not a budget video production option.

An analog video signal is a continuous waveform. Small disruptions to that otherwise smooth, continuous signal lead to degradation in image and color quality. Simply dubbing (recording) an analog tape to another tape results in some quality loss. With each additional dub?each added "generation"?images look less defined, colors become increasingly washed out, and the pictures get grainy.

In tape-only editing systems, to make simple scene transitions such as dissolves or to add special effects such as showing videos in moving boxes means doing multiple edits or recording passes. Each pass adds more video "noise" to the tape. Editors using analog tape machines have to plan carefully to avoid creating projects with obvious shifts in video quality from one section to another.

DV makes generation quality loss a thing of the past. DV is a binary signal. A stream of ones and zeros. Unlike an analog signal, which has a wide range of data possibilities and many ways for electronic equipment to misinterpret it, a digital signal rarely loses quality during transmission and doesn't suffer from generation loss.

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Home satellite systems that use those pizza-sized dishes are digital. To reach your home those digital TV signals travel from an earth-based transmitter to a satellite in geosynchronous orbit (22,000 miles into space) back to your parabolic pizza pie receiver?44,000 miles and the picture is crystal clear.


Although some noise may creep into the signal, electronic equipment easily can filter this out because all it's looking for are zeros and ones (see Figure 1.2). Little ragged edges on the signal rarely are large enough to lead to obvious signal quality loss.

Figure 1.2. Signal noise can dramatically affect analog signals but has virtually no impact on binary signals.

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More importantly for our purposes, multiple DV edits or dubs do not lead to generational loss. The signal simply remains zeros and ones. You are no longer constrained to limiting your creative considerations to ensure low-noise video. No matter how many edits you perform, no matter how many layers of elements you pile up in a clip, there should be no discernible noise or degradation to fidelity.

Therefore, your first order of business is to buy, borrow, or rent a DV camcorder. A purchase will run you between $500 and $4,000 (see the upcoming sidebar review of a half dozen higher-priced prosumer products). Two things drive camcorder prices: features and chips. As you move up the price range you'll see an increasing number of competitive features?longer focal length lenses, larger LCD screen viewfinders, programmable settings, and fast shutter speeds. But the biggest differentiator is that top-end camcorders have three chips, versus a single chip for lower-priced products.



    Part II: Enhancing Your Video