Sync and Video : Working with Synchronization : Configuring Pro Tools for SMPTE : Setting a SMPTE Session Start Time (Start Frame)

Setting a SMPTE Session Start Time (Start Frame)
The Session Setup window also allows you to set a SMPTE Start Frame for your session. Video work tapes are rarely striped beginning at a SMPTE frame address of 00:00:00:00. You can quickly enter a start time for your session based on an appropriate frame number from your project tape. The Pro Tools SMPTE-related functions (such as Spot mode) will then use this value as their reference for the session’s start point.
Start Time When Striping Tape
If you are generating timecode, it is a good practice to stripe your timecode beginning at 01:00:00:00 (subtracting time for the head format, such as initial black, bars and tone, or logos). This prevents problems that can occur with some synchronizers when the striped timecode crosses from 23:59:59:29 to 00:00:00:00 (commonly referred to as the “midnight” boundary).
To set a SMPTE Start Time for your session:
1 Choose Setup > Session.
2 Enter a SMPTE frame number in the Session Start field.
To capture an incoming SMPTE address as the session start time:
1 Click in the Session Start field.
2 Begin playback of the timecode source.
3 At the location where you want to capture the incoming value, press Equal (=) in the numeric keypad.
4 Press Enter to accept the value. You can then edit the captured address. The session uses the frame number you enter as its SMPTE start frame when online.
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If there are existing clips on the tracks and you are changing the original SMPTE start frame to a later time (from 00:00:00:00 to 01:00:00:00, for example), all existing clips on tracks will remain in their relative positions, but will start later by the time value added to the start frame.
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If you are changing the session start time in an open session in which tracks already exist, a warning dialog appears when you press Enter. Choose from one of two options:
Maintain Timecode
Places the additional session time at the start of the session, and keeps existing clips in their original timecode locations.
Maintain Relative Position
Places the additional session time at the start of the session, and maintains the relative position of existing clips to the new start frame. For example, if you change the session start frame from 01:00:00:00 to 00:59:00:00, Pro Tools adds one minute of session time to accommodate the new start frame, and moves all existing clips earlier in time to maintain their relative position to the start frame.