Digital BW, The Print

> From: Paul Roark <paul.roark@...>

> 
> B.  Color managed workflow:  Print with Preview set to "Let Photoshop
> Determine Colors" and an ICC make with Create ICC inserted, driver set to No
> Color Adjustment.
> 
> 1.  Gray Gamma 2.2 working space -- 90-100 separation = 3.4;
> 
> 2.  Dot Gain 20% working space -- 90-100% separation = 8.2.
> 
> Here the 90 - 100% separation of the Gray Gamma 2.2 print is clearly
> compressed relative to the Dot Gain 20% print.

It's not "compressed".  It was closer to begin with.  By saying it is
compressed you suggest that something in the printing narrowed the gap.
What really happened is that when you assigned GG2.2 to the step wedge you
gave new definition to the 90 step.  You in effect assigned GG 2.2 because
when there wasn't a profile attached to the step wedge PS used your
workspace as the profile instead (ie it assigned the workspace for you -
temporarily or on-the-fly).  90K in GG 2.2 is much darker than 90K in DG20.
So when you print them you'd expect the 90 patch from GG2.2 to be darker
than the 90 patch from DG20 and hence you'd expect the respective spread to
be narrower.  This is also depicted on screen.  So colour management is
doing the right thing printing the 90 patch darker for a GG2.2 step wedge
than for a DG20 step wedge.  (Same arguments for GG2.2 vs GG1.8.)