Audio Setup Considerations: File Start
The start time on the files sometimes depends on the timecode of the first frame of picture.
If one is working for home video, the minimum “run-up” is for the audio files to start at 00:59:52:00, leading into a head pop at 00:59:58:00, and a first frame of picture at 01:00:00:00.
For theatrical release, when work is finished by reels, it is common to have the timecodes follow the reel hour. Thus, the “Picture Start” frame in the head leader for reel 3 would be at 03:00:00:00, the head pop at 03:00:06:00, and the first frame of picture at 03:00:08:00.
This eight-second pre-roll is minimum, and options for longer times include matching pre-roll of home video masters or simply having additional time for voice slates (with channel IDs) and head tones.