QTR-Quadtone RIP

Hi Ed,

The procedure I used was outlined in an article on the NorthLight
Images website for using PrintFix Pro to linearise the QTR output.
Here are the steps that I used:

1. Converted the Step-21-gray file (contained in the eye-one folder)
to the QTR-Gray-Photo Paper space, saved as a tiff and printed the
file using QTR and the Ilford Smooth Pearl curves provided on this
website.
2. Read the L values of the printed 21 step scale and entered these
into a tab delimited text file.
3. Used QTR-Create-ICC program to convert the tab delimited text file
into an icc file.
4. Converted the original Step-21-gray file into the new icc space
created in step 3, saved this file and printed again in QTR
5. A reading of this new print showed that the scale was linearised.
However when compared to the screen view of the image in Photoshop on
a calibrated display, the printed version is slightly darker or heavier.

So the process did linearise the gray scale, but the new icc profile
does not create a close softproof match. The print doesn't look bad at
all. It looks good when viewed by itself, but when compared to the
display verion, then some difference can be seen. The difference is
not dramatic, but enough that it is not possible to accurately adjust
a gray scale image in Photoshop based entirely on what is viewed on
the display.

There is something not quite right and I am not sure exactly what
might be causing the problem. I prefer not using the gamma adjustment
slider in QTR to correct the discrepency between the printed and
display version, since I assume this would cause the output to no
longer be linear, thus in some respect degrading the image quality.

Thanks for input on this.

Best wishes,

Ken


--- In QuadtoneRIP@yahoogroups.com, "edrudolpho" <erudolph@...> wrote:
>
> Hi Ken.... yes, QTR-Create-ICC is what I was talking about.  Did you
> use it according to the instructions, i.e., did you measure one of the
> reference tiffs?
> 
> Ed
> 
> 
> --- In QuadtoneRIP@yahoogroups.com, "prof_mgt551" <prof_mgt551@> wrote:
> >
> > Ed, thanks for your suggestion. I am using QTR 2.4.1 and understood
> > that you can create your own curves, but didn't understand this to
> > mean I could create my own soft-proof ICC profile that I could use in
> > Photoshop to soft proof my image.
> > 
> > I used a curve posted on this forum for Ilford Smooth Pearl, printed a
> > gray scale and used the QTR-Create-ICC program to linearise the
> > output. I have tried using the new Linearised ICC profile to softprood
> > the image in Photoshop, but it is still on the heavy side (too dark).\
> > 
> > Is QTR-Create-ICC program what you are referring to, or is there some
> > other capability that I am not aware off?
> > 
> > Thanks for sharing your thoughts,
> > 
> > Ken
>