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Besides software to play 1000 (or 2000) MP3 tracks, and hold vCard format text too, the iPod is a versatile pocket-sized Toshiba 5GB (or 10GB) FireWire Hard disk.
Just what’s needed for editing iMovies, or for use with Final Cut Pro …to edit video unaffected by, say, a PowerBook’s constant background ‘house-keeping’ reads-&-writes. A suitable external video-capture FireWire disk will generally run more smoothly than the necessarily task-sharing internal Mac hard disk.
I tried using my iPod as a capture disk (after temporarily wiping all music tracks from my iPod) I was greatly underwhelmed: it does NOT do the job!
FireWire’s a fast file-transfer facility – but its speed can be drastically reduced by slow devices attached to it.
Many CD rewriters – the early portable Freecoms, for instance – won’t perform faster with a FireWire interface instead of the slower USB connection. That’s due to the slow CD-RW writing speed knocking down overall performance.
Disks for use with Digital Video must write at a minimum of 3.6MB per second for sustained transfer of video between a camcorder and storage disk. That equates to roughly 1GB storage for every 5 minutes of video. The FireWire interface (theoretical speed up to 50MB per second) easily handles 3.6MB of data transfer, but not all hard disks can receive and store data at that rate.
Capturing DV onto my G3 500MHz FireWire PowerBook’s internal Toshiba 20GB hard disk has never been a problem (nor capturing video onto my external ‘backup’ 20GB LaCie hard drive). But, my iPod captures about 7 seconds of video, then there’s a glitch and the PowerBook screen goes black for a couple of seconds, and then capture resumes. But two seconds of video is lost.
I ran the latest Norton SystemWorks 2.0 “System Info” disk-speed check on my internal hard drive, on my 5GB iPod, on the external 7200 rpm LaCie drive, and on an external Western Digital 5400 rpm 20GB drive.
“And the winner is!” …my internal hard drive! The iPod’s transfer rate is w-a-y too slow for video editing and the other two disks never matched the speed of my internal drive! (though I had just defragmented the spare space on the internal disk, so that influenced things a tad!).
The internal PowerBook Toshiba hard disc – according to Norton – writes a 1k file at 2594k/sec (just under the DV speed of 3.6mb/sec), does a 4k sequential write at 8133k/sec (that’s 8mb/sec), and a 16k sequential write at 15248k/sec (that’s 15mb per second, far more than fast enough) – whereas my iPod writes a 1k file at 505k/sec (far too slow), 4k at 1971k/sec (still too slow), and 16k at 5520k/sec (that’s 5.5mb/sec which is OK).
The iPod writes at anywhere from a fifth the speed to about one third the speed of my internal hard disk. But it keeps up, above that crucial 3.6MB/sec speed only for short bursts of file-writing, and doesn’t reliably capture more than about 7 seconds before it’s overloaded.
Norton rates the overall performance of my G3 PowerBook internal hard disk above that of a PowerMac G4 500MHz (..surprising, but this old black 256MB FireWire PowerBook always seems speedier than any new white G4 PowerBook I’ve tried!) – but the iPod’s disk is rated scarcely faster than the old PowerBook 3400.
