Digital BW, The Print

Several times in printing with the MIS VM on a 1270 (PC), the image 
is lightening up in the process of applying the curves (for me at 
least).

My monitor is calibrated via Spyder and software so I don't want to 
change my monitor gamma settings (and it hasn't chirped at me that 
they have changed from the calibration).

Since the VM is working in a partitioned workflow I'm uncertain what 
direction to make adjustments in?  I thought about using an 
additional color balance layer?  Directly changing the curves 
themselves (all lower)?

I played at printing a step-wedge and scan the results this weekend 
and got the Newstep21 to separate more in the 95-100 range visually 
but not registering it in the scan & sample.  In the process I think 
I just muddied the 75-85% zone.  The stepwedge with no modification 
has a slight jump in tone at 70% and indiscernable separation from 95-
100%.

In the Roark developed curves it doesn't quite make logic to me that 
there are a couple that slightly invert in areas - I keep wanting to 
smooth that out mentally?

QUESTION RESTATED simply - best direction to darken the printing 
process without changing monitor gamma?

Thanks (on or off-list),
Cleavis