QTR-Quadtone RIP

Steve,
I have run into the same concerns that you have expressed. I had been  
using a scanner, an Epson Perfection 3200 Photo, to do my profiling. I  
have since acquired a PrintFix Pro densitometer which makes the measuring  
part of the process easier but has not alleviated the issues in profiling.  
I found the same issues in that I would go through the process of curve  
creation in QTR, linearize it and print the 21 step wedge and all would  
look good. In printing, however, I could see areas that did not look  
right. I, too, printed the same test image from NorthLight that you used  
and saw non-linear steps where there should have been none. Fiddling with  
the controls in QTR did not seem to help. I then imported the data from  
the .quad file that QTR generated into Excel to see what was going on. The  
individual ink curves were not very smooth. I generated a combined curve  
using the same parameters of relative ink densities that I used in QTR.  
Looking at that curve I could correlate bumps in the curve to where I was  
seeing steps in the printed test image. I am using Jon Cone's NK7 ink set  
in an Epson 2200. So, I next imported the data from one of Jon's supplied  
profiles such as the one for Moab Entrada Natural into Excel also. When  
comparing the two profiles, it was immediately obvious that Jon's  
individual ink curves are much smoother and had more overlap. The combined  
ink curve was also much smoother.

Now what I do is try to get a set of curves as close to matching the  
paper, either from QTR's curve creation process or based on one of Jon's  
profiles, and then manually modify the data in the .quad file to smooth it  
out to match the paper's properties. I do not yet have an automated way of  
doing this so it is a painstaking and time consuming process. Generally, I  
use densitometer measurements from the 21 step chart and visual  
inspections of the test image to determine what changes I need to make in  
the data. I make the changes where needed, smooth out the data points  
around the area and reprint the tests. After two or three iterations, I  
have a pretty good profile. I just need to figure out how to make this  
process easier. I know Jon charges $99 for this service to make a custom  
curve. Since I am retired and this is just a hobby not a money making  
pursuit, I have more time than money so I have to do these curves the hard  
way.

I have also peviously brought up these issues on this forum and not gotten  
any responses. If there is an easier way of doing this that I am missing I  
would be glad to be shown how to do it. Meanwhile I will continue down  
this path and will try to figure out a way to make the process more  
automated.

Steve T.


On Fri, 13 Mar 2009 06:20:53 -0700, alleycatnmilo <stuff@...>  
wrote:

> Hi All,
>
> After a long relationship with Imageprint, I find myself now looking for  
> other solutions to make BW prints on my Epson 4000 with papers that are  
> unprofiled for IP (and they are NOT getting one thin dime more from  
> me!).  Having arrived at QTR, I've spent some time working through the  
> process, and I have some questions...
>
> Rather than simply following the curve/linearization steps with a new  
> paper and calling it good, I've spent some time trying to duplicate the  
> existing/known good profile installed with QTR for Moab Entrada Natural  
> paper; that is, I've tried to build, from scratch, following the  
> information that's out there for QTR, a paper curve/profile (what should  
> I call this, exactly?) that is at least as good as the one that comes  
> with QTR.
>
> snip! . . .
> Steve
>
>
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