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Re: Sony HD Telecine Review

<< My biggest potential problem with the return of the film chain approach is
not film handling, but mechanical maintenance. (deletia) Video facilities (as
opposed to optical houses or film labs) are not used to complicated
mechanical movements, or the level of maintenance probably required, at
either the engineering or operational level. >>


Assuming Sony even used a mechanical intermittent sprocket motion, there is
no reason it should be complicated or difficult to maintain.  Types such as
the Geneva motion have been used in film projectors since at least the turn
of the century and have two or three moving parts at most.  The complexity is
in manufacturing them to the required degree of accuracy and hardening the
cams and pins sufficiently to last a reasonable length of time.  Maintenance
is keeping them properly lubricated, and troubleshooting means that you
replace the parts with a new set when they wear out (as evidenced by
excessive noise or jitter).  I'd have to wonder about any video maintenance
department that can clean tape paths and replace upper drums and pinch
rollers in VTRs, but couldn't take adequate care of this type of device!

However, there is a reason to be concerned about this type of machine,
particularly when dealing with valuable one-of-a-kind films.  Most film tears
and breaks start with torn or damaged perfs, so if you're going to stress the
perfs by using them to move the film, there's always a possibility that a
previously damaged or weakened one will give up the ghost.  This is
particularly troublesome with old, archival footage where shrinkage makes the
perfs fit tightly on the sprocket teeth.  On the other hand, most of us have
probably seen test loops (if nothing else) with frames that are literally
ripped halfway through, but still make it through capstan-type telecines
without further damage.  To minimize the possibility of trouble due to bad
perfs, one must completely inspect the film and repair any suspect perfs,
before putting it on the machine.  This is not a common practice in telecine
now, and the extra time and labor could become an issue.

Cordially yours,
Christopher Bacon

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