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Problems - da Vinci cont.
- To: multiple recipients of <telecine at sun.alegria.com>
- Subject: Problems - da Vinci cont.
- From: philip budden <phil at das-werk.de>
- Date: Wed, 02 Jul 1997 10:38:50 -0700
- Old-Return-Path: <phil at das-werk.de>
- Organization: das-werk
- Resent-Date: Wed, 2 Jul 1997 01:44:25 -0700 (PDT)
- Resent-From: telecine at sun.alegria.com
- Resent-Message-ID: <"QKbrkC.A.E6B.iThuz" at sun>
- Resent-Sender: telecine-request at sun.alegria.com
- Resent-To: multiple recipients of <telecine at sun.alegria.com>
Thank you to all those who replied, most of whom, avidly defending their
systems. As several suggested we and da Vinci reps. have already checked
our cabling which is very good. Infact for some of the differential
signals we are using dual-screened twisted pairs, which is infact better
than the single screened cabling which da Vinci supplies. (We have of
course also used the da Vinci cables too.) We have also recently changed
the ethernet cable, but this did nothing.
Most of the faults seem to point to software rather than hardware.
What I neglected to say is that we are using an URSA Gold and the system
is using PAL and mostly 25 f.p.s. This is problably why many of you in
the States are happy with your systems and we are not so; we have the
feeling that the whole system is optimized for 30 f.p.s. and not 25
f.p.s. We have good reasons to belive this:- 1) When you try to edit with
the TLC it usually hits it first time on 30 f.p.s. whereas with 25 f.p.s.
it takes more attempts (though still unreliable). 2) When you load a
confiuration (with 25 f.p.s. selected) it sometime sets the speed to 30
f.p.s. although we have not one configuration with this setting. So,
somewhere in the dark caverns of the software is lurking this 30 f.p.s
default which pops out when you are not looking! Then the question must
be asked: if the 30 f.p.s is still in there somewhere, what other "30
f.p.s. based" default factors are floating about in the software and jump
in the wrong place now and again? Also, why is it that the TLC works
smoother on 30 f.p.s than 25 f.p.s.? Surely some algorithms must be
optimized for 30 f.p.s.?
Another area could be the ethernet system: On a normal PC ethernet it is
common knowledge that if you have too much traffic on the bus it falls
down because there are no free time slots and no machines can get in
without another crashing into its data stream. (This is where a Bus
Contoller controlled system like the MIL.STD. 1553 is much better because
this cannot happen.) I donīt know if on the da Vinci each panel is a
seperate initiator, but if this is the case then there could be problem
if another part is moving alot of "housekeeping" data and the machine
gets busy. Also, if a node transmits a package and there is an
error, it could have not enough time to transmit another one.
Again this is a software problem. Shortly we will put an bus analyser on
the net to see if this could possibly be the problem. (Has anyone tried
What do you think?
Once again, thank you for all your help and we look forward to hearing
from anyone who can help us again.
DAS WERK, Munich
phil at das-werk.de
thanks to Jim Erickson, Rick Pagliaroli, Drexel Williams, and Dave Grey
at Colorlab (Maryland) for their support of the TIG in 1997
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