Path: utzoo!attcan!uunet!know!zaphod.mps.ohio-state.edu!usc!randvax!vortex!lauren
From: lauren@vortex.COM (Lauren Weinstein)
Newsgroups: comp.periphs.scsi
Subject: 8mm vs. DAT (There ain't no free lunch)
Message-ID: <65.UUL1.3#1@vortex.COM>
Date: 11 Nov 90 21:51:34 GMT
Organization: Vortex Technology
Lines: 23

All other arguments aside for the moment, it would appear that with
helical scan, timing track-based technologies, the narrower the tape,
the more precise the required mechanical tolerances, and so the
greater the required manufacturing and operational precision.

In the pro-audio world, where there has been considerable experience
with DAT for quite sometime now, problems with tape interchange and
replayability, purely due to variations in mechanical tolerances,
have been nagging problems.  Sometimes these problems are immediately
apparent with and between particular machines, and sometimes they
only appear as the equipment (and tapes) age.  There have been other
problems as well, such as serious tape dropouts in some cases (this
latter problem may often be related to particular brands of tape, but
many studios now run dual DATs for protection in any case).  While a
robust ECC system makes tape dropouts of less concern, it's still
worth noting.

So while comparing the features and cost-competitiveness of the
8mm/Exabyte vs. 4mm/DAT world, it's probably worth remembering that
as the tape gets tinier, the required mechanical precision that needs
to be maintained becomes considerably greater, with all that implies.

--Lauren--