Sessions & Tracks : Importing and Exporting Session Data : Import Options when Importing AAF or OMF Sequences : Timecode Mapping Options

Timecode Mapping Options
When importing AAF or OMF tracks into Pro Tools, you can specify where the imported tracks are placed in the current session. Times are indicated in timecode.
 
Maintain Absolute Timecode Values
This option places tracks at the locations where they were located in the source session. For example, if the current session starts at 00:01:00:00, and the session from which you are importing starts at 10:00:00:00, the earliest imported tracks can appear in your session is 9 hours and 59 minutes after the start of the session.
Maintain Relative Timecode Values
This option places tracks at the same offset from session start as they had in the source session. For example, if the source session starts at 01:00:00:00 and a contains a track that starts at 01:01:00:00, and the current session start is 02:00:00:00, the track will be placed at 02:01:00:00 in the current session.
Map Start Timecode to hh:mm:ss:ff
This option places tracks relative to their original session start time. For example, if the current session starts at 00:01:00:00, and the session from which you are importing starts at 10:00:00:00, you can reset the start timecode to 00:01:00:00, to avoid placing files 9 hours and 59 minutes from the start of your session.
Adjust Session Start Time to Match Source Start Time
This option changes the start time of the current session to match the start time of the AAF or OMF sequence being imported. When this option is enabled, the Map Start Timecode to hh:mm:ss:ff option (and its timecode entry box) are disabled.
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If the sequence being imported has a later start time than the current session, the Maintain Absolute Timecode Values option is disabled.
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In some cases, when clips in the current session are situated near the time boundaries of the session, enabling Adjust Session Start Time and choosing to Maintain Relative Timecode Values can put clips in danger of being moved out of bounds. In these cases, a warning is displayed and Pro Tools does not adjust the session start time.