Vertical grid lines appear at the beginning of each measure. Is there a way to get 2 or 4 vertical grid lines to appear per measure?

I am guessing this is a question about the PRV. If so, it is controlled by the PRV View Menu "Show Grid Lines" and "Grid Resolution" settings.

Zoom level will also affect this in track view.

 Thanks, guys. In a regular clip pane in the track view, when I turn Grid on, for example, in front, there is a grid line at:
75:01
75:02
75:03, etc.
 
Is there a way to increase the grid line increments in that standard view, to
75:01
75:01:480
75:02
75:02:480
75:03, etc.
 
btw, when I turn on snap to grid, which I don't want to use in this situation, it defaults to 64 increments in a measure, even if I set snap to grid to 1/4 notes.
 

AFAIK, the TV gridlines are based on zoom level (and snap-to-grid being enabled for smaller than 1/4 notes). I have gridlines enabled in front of clips and if >20 measure are visible, only whole note gridlines appear. When <20 measures are in view the quarter note gridlines appear. I am not sure if "20" is the magic number, but it is close to that. This occurs whether snap-to-grid is on or off.
 
With snap-to-grid enabled, more grid-lines appear as you zoom in further.