QTR-Quadtone RIP

Hi, i just created what i thought was a decent curve using a Densitometer, but the 21step 
grayscale that i just printed looks strange. The overall scale is dark, but the transition is 
smooth, until i get to 85%, then the tone drops out completely, 90% looks like 18% gray, 
and 100% looks nice and black. I'm still not sure what color space i should be in, If i 
should be printing from grayscale or Lab, and exactly how to set up the QTR menu. Using 
the other profiles that i downloaded from roy's site seem to give me similar results, the 
prints are overall too dark, and the shadows just drop out, and then pop back to black. I 
think it must be a problem with my color space, but i don't have the info i need to get this 
software to work. Printing without any curve just gives me a dark print, so i'm sure that all 
the heads are working. Thank you for your help,
Michael O'Neill

Hi, i just created what i thought was a decent curve using a
Densitometer, but the 21step 
grayscale that i just printed looks strange. The overall scale is
dark, but the transition is 
smooth, until i get to 85%, then the tone drops out completely, 90%
looks like 18% gray, 
and 100% looks nice and black. I'm still not sure what color space i
should be in, If i 
should be printing from grayscale or Lab, and exactly how to set up
the QTR menu. Using 
the other profiles that i downloaded from roy's site seem to give me
similar results, the 
prints are overall too dark, and the shadows just drop out, and then
pop back to black. I 
think it must be a problem with my color space, but i don't have the
info i need to get this 
software to work. Printing without any curve just gives me a dark
print, so i'm sure that all 
the heads are working. Thank you for your help,
Michael O'Neill