Note value, tempo definition and playback marker

[Tim Mariott]

Sherry

Thanks. That answers part of my question which is how to set the playback marker increments.

But the other part is whether it is possible to select the note value to be used in the tempo definition. It seems almost random as to whether the tempo definition is offered as a number of half-notes, quarter-notes or eighth-notes. Could you explain how Notation decides which note value to use to define the tempo for a given piece? And having decided, is it possible to change the note value used as the basis for the tempo definition?
Regards
Tim