Some applications won’t recognize camcorders connected to a daisy chain — i.e., a string of linked FireWire devices. For example, Apple’s popular iMovie software cannot import footage from DV camcorders attached via daisy chain. Likewise, many applications will not support the simultaneous use of multiple devices connected to your computer with FireWire because of driver conflicts. Typically, an operating system will assign a FireWire port to a single application at the exclusion of all other devices; when the application is shut down, the port is released for other uses.
Although most computers with six-pin FireWire connection can supply adequate power to FireWire peripherals, this is often not the case with digital camcorders. DV cameras require their own electrical sources and must be turned on with their own batteries or AC adaptors before they are recognized by the computer and its applications. Unfortunately, the computer’s internal power supply cannot supply sufficient DC voltage to operate a camcorder.
Never unplug a FireWire cable in the middle of a capture session. Hot pluggable devices are a tremendous convenience to computer users, but disconnecting them while importing DV footage can create a variety of technical problems—computer crashes, disk errors, damaged footage, missing data, and dropped frames, to name just a few. Make sure to stop your camcorder or finish your data transfer before removing a FireWire cable.
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