Yahoo Groups archive

QTR-Quadtone RIP

Index last updated: 2026-04-28 23:12 UTC

Message

Re: Question about linearizing a QuadToneRIP Curve

2007-12-08 by Louis Dina

Hmmm.....MAC.....I'm out of my element now.  I'm a PC guy and use the 
QTR Gui interface.  Someone else will need to guide you on this.  

Lou

--- In QuadtoneRIP@yahoogroups.com, "scott.romans" <scott.romans@...> 
wrote:
>
> Lou, Thanks so much for the response. I neglected to mention that I 
am running all this on 
> Mac OS X, so I don't have the QTR GUI with Curve Creation 
module/Linearization tab. 
> Wouldn't that figure! Please let me step back and detail what I do 
have:
> 
> I printed the 21-step wedge w/o any profiling or changes and then 
spot measured with 
> PrintFix Pro device. This generated a text file with a list such as 
follows:
> 
> 1	96.76
> 2	92.53
> 3	88.14
> 
> etc. I saved the list as a text file. The last few values are very 
bunched up i.e., 20=20.76 
> and 21=20.75. When I have printed on the Arches paper, I've had 
best results using the 
> Moab Entrada FANat Curve, but as these numbers indicate, the shadow 
detail is a bit 
> blocked up. I was hoping to get very similar results as are 
produced with the Moab curve, 
> but open up the shadow detail.
> 
> So I take the txt file, and I can do two things: when I drop it in 
the QTR-Create-ICC script 
> in the QTR downloaded Eye-One folder, I get back another txt file, 
this time with step 
> values in 5% increments, Density values, and Lab values that match 
my readings. In 
> addition, there is the L curve, and I can see where the L's start 
to curve downward at step 
> 95 and 100. In addition, I get an icc profile back.
> 
> Alternatively, when I drop my original txt in QTR-Linearize-Data, I 
get back a similar txt 
> file with the same step, density, LAB, and curve data, but this 
time the last line reads 
> "LINEARIZE="96.76 92.53 88.14 ... 20.75". None of the values change 
from my original 
> readings. 
> 
> Now that I have these files, I am not sure how to use them to 
accomplish my goal of 
> opening up the last bit of shadows. I had assumed I would 
ultimately end up with another 
> curve to choose from in my QTR printer dialog box that would 
produce desired results. 
> Am I supposed to use the txt file with the Linearize message to 
create a curve or am I 
> supposed to use the icc profile? If so where do I put these files 
or how do I use them?
> 
> I did try running a print with my QTR-ArchesInfinity.icc profile as 
both the Proof and as 
> the Printer Profile (letting Photoshop manage color); in the QTR 
printer dialog box, I didn't 
> select any curve because I don't have any new option to choose 
from.  This generated a 
> very ugly, muddy print--obviously incorrect. 
> 
> If anyone could give guidance on how to properly use the icc 
profile or the linearize txt file 
> in a Mac OS X context, I'd be grateful!
> 
> Thanks much.
> 
> Scott--- In QuadtoneRIP@yahoogroups.com, "Louis Dina" <lou@> wrote:
> >
> > Scott,

Attachments

Move to quarantaine

This moves the raw source file on disk only. The archive index is not changed automatically, so you still need to run a manual refresh afterward.