QTR-Quadtone RIP

--- In QuadtoneRIP@yahoogroups.com, "Tom Moore" <r.t.moore@r...> wrote:
> Jamie
> 
> I see you have xrite's toolcrib and a densitometer. What I do, is
print a
> step wedge (I use the 21 step), and then measure the density of each
step.
> Using toolcrib, I pop the density readings into an excel spreadsheet
that
> displays the densities as a graph. I can see how the density of each
step
> increases over the 0% to 100% black range. It should be uniformly
increasing
> over the range (i.e. it should not decrease). I usually end up
printing the
> stepwedge several times as I adjust the Highlight, Shadow, and Gamma
> parameters to bring the density curve nearer to linear. My
spreadsheet is
> set up to store and plot the density values from a number of runs as I
> (hopefully) get closer to my final curve. Plotting several
stepwedges lets
> you see the effect of changing the parameters.
> 
> The spreadsheet also can compute L* values from density so I can use
Roy's
> utility to create an ICC profile of the final curve for previewing in
> Photoshop.
> 
> Tom Moore

Hi Tom

What is the formula to convert dMax to *L? -or- can you share the
spreadsheet.

Also, does anyone know if there is an "Ideal Densities for Various
DMax" chart available that goes as los as dMax 140. I have some not so
great matte paper that maxes out at 142 on my UC 7600.

Thanks!!
tim