QTR-Quadtone RIP

--- In QuadtoneRIP@yahoogroups.com, "grayscale2008" <pm2003@...> 
wrote:
>
> Hi guys!
> 
> I am new to QTR 

Welcome!

> and I am trying do create some curves for my EPSON
> 2100 using Hahnemühle Photo Rag with the original UltraChrome ink.

Frankly, I thought these curves were already shipped with QTR but I 
checked and indeed they're not. You may try the the Epson Enhanced 
Matte curves though as EEM is rather similar to Photorag.

> Here are my questions:
> 
> 1.) I want to linearize my curves now. Which file for measuring 
should
> I use? 
> 
> There is a "21step.tif" in the "QTR"-directory and there are several
> Step-21*.tif files in the "Eye-One"-directory.

From a fundamental point there's no difference. It depends how you 
want to proceed. This is how it is with an Eye-one and Measuretools 
download from the Gretag-MacBeth website (URL is in the QTR doc):

The "21step.tif" and the "step21-gray" are both single sequential 
stepwedges. I always use a modified version of the 21step.tif as I 
can easier align me Eye-one on it. But then I tell Measuretools I'm 
using step21-gray.

Step-21-random is meant for a line scanning mode in Measuretools. 
Instead of measuring the 21 areas one by one it should be possible to 
have one single movement over the step wedge. Measuretools in then to 
detect the transitions between the areas. Therefor neigbhoring areas 
must have sufficient contrast, not true for the sequential step 
wedge. However, I've never been able to get this feature to work 
well. So I just have a manual process. So  use the sequential one.

The setp-21x4-random allows for four measurements thus averaging out 
noise.

As matter of fact, I do have made a sequential QTR-21x4-gray.txt file 
(the input files that measure tools reads) to allow for the averaging 
over four measurements using the sequential stepwegde.

So all and all, it's 1) mostly personal preference 2) depending if 
you want to add accuracty by averaging out some noise.
 
> 2.) Which file should I use to create a icc profile?
> 
> There are 3 exe-files in the "Eye-One"-directory:
> 
> QTR-Create-ICC.exe
> QTR-Create-ICC-RGB.exe
> QTR-Create-ICC-RGB-bpc.exe.

I'm afraid I can't help you on this one as I don't use them