QTR-Quadtone RIP

Steve,
 
 
> > You could also just print the necessary 21-step test strips to do a fresh partitioning.  You might end up with a closer fit to the ink.  But you may not want to get into this yet....
 
 
> Do I start from a completely zeroed out *.qidf file without any information entered into the fields?


Usually you start with a Calibration Mode print that prints 21-step test strips of all the inks.  (With a 7600 and if you just making the LK-K partition, you can speed this up by making individual test strips, but that gets into how to make them.  So I'd stay at the moment with the normal procedure.)  Have the Calibration Mode print set to print at 100% limit (the slider near the bottom of the page.)

(By the way, I'm PC, so I'm not sure what a Mac interface is like.)

Use the 100% calibration curve to set you ink limits in a new, *.qidf file.  Be sure to zero out the linearization tab also.

Print another Calibration mode at the K ink limit.  The point is to get a 21-step print of the black ink printed at its ink limit.  This is used to figure the relative densities of the midtone inks.  The boxes you'll need to fill in in the Curve Creator are the ink limits and relative densities of the black and LK inks to allow the system to partition these.

(Or 21-step with a profile that is simply K 0-100 [or ink limit].  I often make straight line curves for specific purposes just to save the time of printing an entire Calibration mode print.  To do this, hid Load curve (in drop down menu just below the ink name in the Curve Creator), press Curve button, go to point list, enter (0,0) and (100, 100) [or ink limit] -- be sure it's a straight line curve.  I call name these curves, e.g., "K-0-100.")



> The minimum separation is a problem, but I only have an Epson Scanner to scan the image then convert to Lab mode and measure the steps with the "Info" window.

Scanners work fine for measuring relative densities of grayscale inks.  I don't trust them for color or absolute readings, but you don't need these at this point.  That said, I think for B&W work the ColorVision spectro is a very good tool to have and a good value.

Hope this helps.

Paul
www.PaulRoark.com