Pyro Industries API-1394PCI Manuel d'utilisateur télécharger pdf (Page 54)

■ USING A DECK FOR CAPTURE

When using RS-422 with non-FireWire decks, you need a transcoder to convert

video and audio data into a FireWire signal that can be connected directly to your

computer or the optional Mojo.

Transcoders vary greatly in terms of connection and quality. They range in price

from as little as $295 to thousands of dollars, depending on the quality of the video

signal and the manufacturer. Some transcoders can be purchased at a local computer

store. Others must be purchased through a professional video products distributor.

Video Connectors

If you are going straight FireWire from your deck to a Free DV or Xpress Pro, you

don’t need to learn about the different types of connectors. It is a good idea to review

this material, however, because you might find yourself using a different format deck

from time to time.

There are three types of video connectors that can be used with transcoders and

Mojo. The first is a BNC connector. When attaching a BNC connector to Mojo, you’ll

need an adapter from BNC to RCA, which is the second kind of video connector. A

third type of connection, S-Video, will be discussed later in the chapter.

BNC CONNECTORS

BNC connectors come in different types. It is important that you use the correct type

of BNC connector when connecting to your video deck. For example, a thin Ethernet

connector (RG58A/U or RG58C/U; see Figure 2.9) is not recommended for use with

professional video equipment, but it looks very much like a 75 ohm video BNC con-

nector. The reason is that the center conductor of this connector (which looks almost

exactly like a video BNC connector) is too thin. When you use these kinds of connec-

tors, you lose fidelity of the video signal. Even worse, if you combine thin Ethernet and

video BNCs, the signal can flutter and the quality of the video will suffer greatly.

RCA OR PHONO CONNECTORS

The other type of video connector is called an RCA or phono connector, as shown in

Figure 2.10. These are much more common and can be purchased in department

stores. These types of connectors are considered unprofessional to some, yet they work

just fine on transcoders and Mojo. The only objection that I have to these connectors is

that they do not have a locking bayonet mount, as BNCs do.

Figure 2.9 Video BNC vs. thin Ethernet BNC

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Pyro Industries API-1394PCI Manuel d'utilisateur Page 54