QTR-Quadtone RIP

Update:

I uploaded the curve files to the FILES section.  I am trying to gain some proficiency in creating curves using a scanner to give me some measurements.  Please take a look at it and see what you think of the curve?  If you have an R1800/R800 with the Photo Black in the usual place try printing it on some Epson Premium Photo Glossy paper and tell me what you think of the appearance?  Does it seem right?

I had a couple of experimental curves for this.  On one I tried to get fancy.  I used my Epson 2400 scanner and an IT8 reference card.  I scanned both the IT8 and the 21-step printed image (with no linearization values, just the 60% ink limit).  I then used Photoshop to make a curve layer in the scanned image to get the L values of the IT8 to be correct.  Then I measured the L values of the 21-step print and entered those values into the linearization table.

The printout I got using the linearization was clearly wrong.  The 5% step was barely visible as something other than paper white.  So I guess that idea is a bust. 

For the curve I uploaded, I just scanned the non-linearized print, and set the paper to 100 lightness and the blackest as 0 lightness, and let everything else fall where it may.

Any suggestions?

-Tony