Digital BW, The Print

Hi, everyone.

How do people adjust their images for projection in a digital 
projector as far as black and white point? For printed images one 
has to determine at what point the printer is incapable of 
distinguishing between gradations of black and white since levels of 
b/w outside those levels of gradations will not be distinguishable 
in the print. When it come to digital projection does one have the 
same concern, ie, gradations that are not visible? I have noticed 
when I project an image prepared for print that it looks washed out 
when projected digitally. I've been told various reasons for this 
that I won't go into now. I've tried a curves adjustment, just 
pulling the curve center darker and that was not completely 
satisfying. So...should i do a levels adjustment and reset the bw 
points only and by what amount, or what?

Thank you for your ideas.

Charlotte