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Re: ACMADE code

At 02:21 PM 7/7/97 +0000, Basil Pappas wrote:
>1 frame errors are common; rarely is the audio field accurate.
>The 35mm film/mag process allows for 1/4 frame accuracy, yet
>these same rolls sent to telecine commonly come back with 1/2 to 1
>frame errors thruout the transfer. I myself have seen
>one of the top colorists in NY proclaim "that's close enough".
>Close is not good enough. If it's not field accurate, it's NOT ACCEPTABLE.

Now I understand where your coming from. Your damn right it's NOT ACCEPTABLE.
Their are several reasons I can think of right off the top of my head that 
would "throw things off" by 1/2 or 1 frame.

1) Most telecine rooms today use Audio delay boxes to compensate for 
the video delay caused by digital still stores, Noise reducers, 
encoders etc. Allot of these rooms have different delays
depending on whether your doing a film to tape session or a tape to
tape session. All the colorist needs to do is forget to reset the
audio delay box from the previous session and bam! You are out 1 or
more frames. And then make the biggest mistake of all and not
check the "2" beep and let go out the door that way! I never
liked the audio delay boxes for interlocked jobs and preferred
instead to compensate for the video delay by advancing the film
3 frames (or whatever your delay is) in the telecine gate and
 then making sure the "Start Mark" on the Mag is sitting squarely
on the Audio head.(If the dubber has "lifters" you must push then
in to be sure your on the right sprocket.) Then interlocking the 
dubber to the telecine and rolling the film back to the "start mark"

2) Another goood way to screw up is to put the audio through a delay 
box with the proper settings and not delay the audio TC which is
coming off the same mag. Therefore making the audio correct
but  the  TC NG.
Sorry if I booored some of you. But maybe this could help some younger
colorist that does not deal with audio on a regular basis.

Jim Mann

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