By default, time zero on the video analysis time scale is the start of a movie, because the first frame is marked with a zero timestamp.

Using Logger Pro:
To set zero of the time scale to coincide with the first point used for video analysis, follow these steps:

-Double-click the movie to open Movie Options.
-Check First VA point defines movie time zero in the Video Analysis options.

Using Video Physics:
The Offset feature is not built into Video Physics. To do this analysis on your data, you will need to export the data to Graphical Analysis App. Once your data is in Graphical, you can add a calculated column: “Time” – the offset value.

-Switch to table view
-Tap the three dots in the header of the time column
-Choose Add Calculated Column
-Set name to something like time offset
-Set units
-Tap Insert Expression
-Choose X+A
-Set X = Time
-Set A = The negative of your offset value. That is, the timestamp on the frame of the video where you want time to be zero.
-When creating graphs, use your new column on the horizontal axis instead of the original Time column.

Using Vernier Video Analysis:
This application automatically sets the first marked data point to be time = 0 in the data table and on graphs.