QTR-Quadtone RIP

Hi

I have a newbie question regarding which percent to select on the Ink Seperation Test page.

I am on a PC using the Epson 2200 printer.  When I print the Ink Seperation Test Page I get black, light black and 5 color lines.  Looking at the DMAX percents of the color lines, the DMAX values are at 90% or so where as the Black and Light Black DMAX values are more like 80% or less. 

Am I to use just the Black and Light Black lines for the % selection or am I to use the color lines as well in selecting a percent value?

Thanks for the help.

Bruce