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Aaton Code - dailies



  Hello,
     I was recently involved in a series of tests to determine the
practicality of using video assist recordings for off-line editing.  As
you have pointed out, the camera must be running at a video compatible
rate ( 23.98 fps  or  29.97 fps).  Also, the audio time code must be
recorded at 29.97. What you did not mention is that the time code must
be Drop Frame.  If you set up a configuration in Keylink for 23.98 or
29.97  telecine and  camera speed the only audio code option is 29.97
Drop Frame code.
     Once you have finished the off-line edit you will be faced with the
problem of matching the telecine transfer to the edl.  Because of the
3:2 pull down in a 23. 98 fps telecine this can be tricky.  At any given point
you can expect to be off by at least a field.  And these discrepancies can
accumulate.  In other words,  you may find yourself off by several frames.  Not
good.  To avoid this you could shoot at 29.97 fops,  but your budget may suffer
from 25% more film usage.  Another option would be to re-digitize the select
material from the telecine transfer and correct the cut prior to finishing.  Of
course this would also require the telecine operator to stop at each take to
create proper pre-roll on tape.  The ATN or other list could then be created
with the exact same pull-in used in the original digitizing,  further
simplifying things for the editor while adding to the telecine time.
   Now for the audio code.  You might say that the camera code will
match the audio code exactly, but that is not likely.  Most of the time
you will be forced to offset the code by at least one frame to establish
sync.  In the telecine session this offset can be entered in Keylink,
but that would ruin any chance of matching the code recorded from the
video assist.  You will have to enter the offset at the audio playback
deck and deal with it in your mix as well.  Another good procedure to
follow in production would be to record the camera code in a window and
VITC , and the audio code as LTC for later comparison.
   As far as pulling negative in the future goes,  there is a simple
answer.  The Keylink will read the Keycode and display it in a window if
desired,  as well as inserting it in the VITC and the Aatonroot list.
This should be perfectly accurate with the exceptions that Drop Frame
time code and  3:2 pulldown issues will have to be dealt with.  And the
original edit will not include Keycode, so this process will be a
separate project.
  So,  are you prepared to take this on?  Can you guarantee that the
camera will be properly jammed to the sound?  Can you be assured that no
off-speed material will be shot?  What if the recordist accidently uses
NDF code for a portion of the shoot?  These situations and others are
easily dealt with under normal conditions but when using the video
assist for editing they can spell true disaster.  My suggestion is to go
ahead with great caution.  Many people have gone to great lengths to
make this process possible and with proper care it can work.  Go for it.
                         Randy Coonfield


to:   IN:tmeerakker at magpost.com
cc:   IN:telecine at xyzoom.alegria.com



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