Digital BW, The Print

I have some prints, maybe 
> 10% of my prints, that have areas of light silvery tones.  This is 
> the region where ImagePrint puts down dots with blank paper in 
> between, whereas the PiezographyBW driver I'm using more or less 
> fills this space with light gray ink, obscuring the paper base.

Ron,

I understand what you say and certainly can't dispute what you observe. All I 
am adding to the discussion is that "in theory", which means under ideal 
profiling conditions, the "loose dots" and the "filled gray" should result in the 
same density. IOW, let's say we take a 10% gray. Whether we make it up of 
darker dots spread apart or lighter dots packed tighter together, the result 
should read the same on a densitometer (with appropriate aperture) and 
seem the same to our eyes.  



 I should add that this luminosity is best observed when 
> the prints are illuminated indirectly.  I don't see this advantage 
> when illuminated by strong direct lighting.



Well,...  here is another rather big factor all these theoretical discussions leave 
out: the conditions under which we view these prints. I recently made a test of 
an "ordinary" print on EAM with PTs and an ultra-dmax print using the 
Ultrachromes (2200) on Ilford Smooth Pearl. Of course the difference is 
staggering if you put them on a wall with a spotlight on them, framed without 
glass. But leave them on a table in the middle of a living room lit by diffuse 
daylight, and the EAM print is starting to look pretty good!  It's no magic. The 
diffuse reflections in the room lower the perceived black in the semiglossy 
surface. A whole huge dmax difference between 1.60 and 2.40-something is 
leveled by lighting conditons. 

Your experiences seem to fall in this category where theory meets perception.
And, speaking of perception... the same crappy EAM paper (in the tests 
above) looked terrific when used with my Sepia profiles on the 2200 and 
dead flat out of the 7000/PTs. The dmax difference was minimal (like 0.05). It 
was the coloration that gave  richness to anotherwise mundane paper. Go 
figure...  

Antonis