How to do it
To activate Calendar Flags you first double click in the diagram and select the Time tab. Activate flags by checking the appropriate box (Auto, Day, Year etc.).

Zoom in and out
Click on any flag to zoom in on that particular hour, day or week etc.

Why not click on a particular day and then using ..
  .. you can step a day at a time through your recording or jump to either the first or last day.

Click on one of the lower flags (w23, Jun), as illustrated at left, to zoom out again.