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318 Chapter 19: Video Post-Production
There are two key things that can cause a Video
Postqueuetofail.Thefirstisincorrectordering
and nesting of events in the queue. The second is
faulty positioning and/or overlapping of the range
bars.
When you come up again a problem, especially if
you’re attempting to set up a very complex queue,
the best way to diagnose the problem is to create
a new queue that s hould only result in the effect
that is failing. If you can get the simplified queue
to work, you can compare it to the structure of the
failing queue to see what mig ht be out of order.
Her e are two very common scenarios that look like
they should work but ultimately don’t give you the
result you expected. These examples are shown
in their simplified state, but could ver y easily b e
buried in more complex queues.
• The object simply disappears instead of
fading out.
The first example illustrates a problem where
you expec t the scene to render for fifteen frames
before fading to black to finish the animation.
However, at frame sixteen, the scene abruptly
goes black.
This queue shows all the correct events in the
proper order in the queue. The problem is
the timing and positioning of the range bars.
The most likely cause of this problem is using
the
Abut Selection (page 3–325) when it’s not
necessary. In order for the Fade event to work
properly, it needs to overlap the animation for
theamountoftimeyouwanttofadetooccur.
You need to take into account the number of
frames where the scene actua lly fades.
To fix this queue, you have to decide how m any
frames over which the fade will occur. Let’s say
youwantthescenetofadetoblackoverten
frames. You would need to drag the rig ht end
of the Perspect ive event range bar ten frames to
the rig ht to overlap the Fade event.
• Theobjectglowsduringrendering,butnot
in the a nimation.
This second example is even more misleading
than the first. The inf uriating thing about this
problem i s that while the scene is rendering,
the object in the scene shows the glow effect.
When the resultant animation is played back,
the Glow effect is not present.
Once again, this queue shows a l l the correct
events, but the problem here is the ordering
of the events in the queue. This problem is
commonly caused when an event is selected
while other events are being added. In this case,
the Perspective event was select when the Lens
Effects Glow and output events were added.
Therearetwowaystocreatethisqueuetogive
you the correct results. You can recreate the
queue and add each event so there is no nesting,