QTR-Quadtone RIP

My apologies to Paul.
John, I dont have the % sign in the file I feed to QTR_create_ICC nor
to the linearization process of QTR Create Curves.
I still think the problem is with the scanner calibration.
Anybody will be so kind to check my workflow and/or give the
Lab_L values measured for the 12-step wedge printed with the R2400
and ABW?
Thanks in advance.
   Daniela

--- In QuadtoneRIP@yahoogroups.com, "John Vitollo" <jvlist@...> wrote:
>
> Roy did not write the tutorial "Making a B&W ICC with a Scanner". It
was written by Paul 
> Roark:
> 
> http://home1.gte.net/res09aij/Making_B-W_ICCs.htm
> 
> I'm not sure this will help but I noticed the Gray values have "%"
sign and Paul recomends 
> this format: 95.00 not "95% ". So I don't know if the ICC profile is
written properly with the 
> "%" sign. Here Roy could answer if % sign will confuse the ICC
building script.
> 
> > I wasted time and material with no  success.
> 
> Welcome to the club! You are not wasting time and material...you are
learning how this all 
> works.
> 
> Best,
> 
> John
> 
> 
> 
> --- In QuadtoneRIP@yahoogroups.com, "dgattarino" <dgattarino@> wrote:
> >
> > Dear Roy,
> > I have followed carefully your instructions in the "Making a B&W ICC
> > with a Scanner" writeup.
> > Here is my workflow:
> > 
> > 1) Open in PS CS2 the 21-step.tiff file. Reply "do not assign any
> > profile" to the request of colour management
> > 
> > 2) Print with preview on EEM with Epon R2400 using:
> >       a) Let printer determine colors
> >       b) intent perceptual
> > In the printer property dialog:
> >       c) ABW with default settings
> > 
> > 3) Scan the print with a HP Scanjet 4870 adjusted in order to get the
> > 0%, 50% and 100% patch according to your writeup.
> > 
> > here are the mesurements done with PS:
> > Gray   Lab_L
> > 0%     96
> > 5%     96
> > 10%    94
> > 15%    88
> > 20%    83
> > 25%    77
> > 30%    71
> > 35%    65
> > 40%    59
> > 45%    53
> > 50%    47
> > 55%    43
> > 60%    39
> > 65%    36
> > 70%    31
> > 75%    27
> > 80%    23
> > 85%    20
> > 90%    17
> > 95%    16
> > 100%   16
> > Kodak Gray Card   42
> > 
> > 4) I used the above measurements to create curve  QTRgui and ICC
> > profiles in QTR_Create_profile.exe.
> > 
> > 5) In both cases, the profiles produced provided very poor results
> > (softproofs and prints dont quite match).
> > 
> > I have done many tests using both QTRgui adn PS with the profiles I
> > created. I wasted time and material with no  success.
> > 
> > I came to the conclusion that the scanner is not properly calibrated.
> > Infact, adjusting the canner settings to match only 3 patches (as you
> > suggest) may be insufficient, unless the scanner is very linear (wich
> > is not, just by looking at the abve table of measurements.
> > 
> > Would you be so kind, please, to give more measurements of other
> > patches of the 21.step.tiff file so I could calibrate my scanner
> > a little better?
> > 
> > Thank you very much 
> > Sincerely
> >   Daniela
> >
>