QTR-Quadtone RIP

Hi guys!

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

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.

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.

Thanks for your help!

Peter

--- 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

Hi Joost!

Thanks for your answer...

Is there perhaps somebody who can answer my question 2???

Or where can I find some more docu about creating curves?

CU

Peter


--- In QuadtoneRIP@yahoogroups.com, "Joost Horsten" <j.h.j.h@...> wrote:

>
> --- 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
>

Hi Peter,

There are 3 create icc programs because some editing programs have
restrictions and anomolies.

QTR-Create-ICC makes a grayscale ICC for printing and softproofing.
Photoshop handles these and works great.

QTR-Create-ICC-RGB makes a functionally identical ICC but it's in RGB format.
Programs such as Lightroom, Qimage, and I think others don't work in
grayscale so you need an RGB format ICC file.

QTR-Create-ICC-RGB-bpc is similar to the above but maps black-to-black
directly.  This takes away softproofing with simulate-ink-black capability.
But some programs seem to get the "Black Point Compensation" wrong with
the above ICC profiles so this ensures that everything is correct.

It's unfortunate that there seems to be variation of how different programs
handle B&W issue but that is the current state of things -- so different ICCs
are needed for them.

Roy

On Wed, Oct 15, 2008 at 9:32 AM, grayscale2008 <pm2003@...> wrote:
> Hi Joost!
>
> Thanks for your answer...
>
> Is there perhaps somebody who can answer my question 2???
>
> Or where can I find some more docu about creating curves?
>
> CU
>
> Peter
>
>
> --- In QuadtoneRIP@yahoogroups.com, "Joost Horsten" <j.h.j.h@...> wrote:
>>
>> --- 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
>>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>

Roy,

Thanks, that's also relevant info for me. Frankly, while really 
appreciating the curve creation and print driver site of QTR I have 
never come to grips with wrt the softproofing side. One of the key 
things that's puzzling me is why it apparently optional for icc 
profiles to support the functions "simulate paper color" 
and "simulate black ink" (I'm using Photoshop CS3 on Windows Vista) 
The icc profiles provided with QTR (gray-lab, gray-matte etc.) DO 
support "simulate black ink", but not "simulate paper color". Other 
profiles that do support "simulate paper color" tend to darken the 
image (substantiall), which I find logical as light reflected on 
paper is of a lower luminosity then white emitted from a monitor. And 
that is what still bothers me most in getting a better monitor-print 
match (QTR curves are fine, monitor is calibrated).

Can you shed some light on this? Is my expectation/wish correct or am 
I missing the point? What is the reason that the QTR icc profiles do 
not support this option?

Thanks,

Joost





--- In QuadtoneRIP@yahoogroups.com, "Roy Harrington" <roy@...> wrote:
>
> Hi Peter,
> 
> There are 3 create icc programs because some editing programs have
> restrictions and anomolies.
> 
> QTR-Create-ICC makes a grayscale ICC for printing and softproofing.
> Photoshop handles these and works great.
> 
> QTR-Create-ICC-RGB makes a functionally identical ICC but it's in 
RGB format.
> Programs such as Lightroom, Qimage, and I think others don't work in
> grayscale so you need an RGB format ICC file.
> 
> QTR-Create-ICC-RGB-bpc is similar to the above but maps black-to-
black
> directly.  This takes away softproofing with simulate-ink-black 
capability.
> But some programs seem to get the "Black Point Compensation" wrong 
with
> the above ICC profiles so this ensures that everything is correct.
> 
> It's unfortunate that there seems to be variation of how different 
programs
> handle B&W issue but that is the current state of things -- so 
different ICCs

> are needed for them.
> 
> Roy
> 
>

Hi Joost,

Actually its just the generic ones provided that don't have a simulate
paper white.  Since I didn't have a particular paper in mind I didn't put a
white end in the profile.

The custom ones though all do have that capability.  You can easily
create your own MattePaper profile using data such as:

Gray Lab A B
0    96  0 0
100  16 0 0

Fill in your Lab A & B values if you like.  Even if you don't have real
measurements, experiment with some numbers for best match.

Roy

On Fri, Oct 17, 2008 at 1:51 PM, Joost Horsten <j.h.j.h@...> wrote:
> Roy,
>
> Thanks, that's also relevant info for me. Frankly, while really
> appreciating the curve creation and print driver site of QTR I have
> never come to grips with wrt the softproofing side. One of the key
> things that's puzzling me is why it apparently optional for icc
> profiles to support the functions "simulate paper color"
> and "simulate black ink" (I'm using Photoshop CS3 on Windows Vista)
> The icc profiles provided with QTR (gray-lab, gray-matte etc.) DO
> support "simulate black ink", but not "simulate paper color". Other
> profiles that do support "simulate paper color" tend to darken the
> image (substantiall), which I find logical as light reflected on
> paper is of a lower luminosity then white emitted from a monitor. And
> that is what still bothers me most in getting a better monitor-print
> match (QTR curves are fine, monitor is calibrated).
>
> Can you shed some light on this? Is my expectation/wish correct or am
> I missing the point? What is the reason that the QTR icc profiles do
> not support this option?
>
> Thanks,
>
> Joost
>
>
>
>
>
> --- In QuadtoneRIP@yahoogroups.com, "Roy Harrington" <roy@...> wrote:
>>
>> Hi Peter,
>>
>> There are 3 create icc programs because some editing programs have
>> restrictions and anomolies.
>>
>> QTR-Create-ICC makes a grayscale ICC for printing and softproofing.
>> Photoshop handles these and works great.
>>
>> QTR-Create-ICC-RGB makes a functionally identical ICC but it's in
> RGB format.
>> Programs such as Lightroom, Qimage, and I think others don't work in
>> grayscale so you need an RGB format ICC file.
>>
>> QTR-Create-ICC-RGB-bpc is similar to the above but maps black-to-
> black
>> directly.  This takes away softproofing with simulate-ink-black
> capability.
>> But some programs seem to get the "Black Point Compensation" wrong
> with
>> the above ICC profiles so this ensures that everything is correct.
>>
>> It's unfortunate that there seems to be variation of how different
> programs
>> handle B&W issue but that is the current state of things -- so
> different ICCs
>> are needed for them.
>>
>> Roy
>>
>>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>

Hi Roy,

That's extremely helpful! I played around a bit with it and see how I
to apply it. Two questions though:

1) Assuming I have correctly linearized my prints curves, I need only
the black point and the white point (and no points in between) as in
your example, right?

2) What's in your experience the best rendering intent? 

Joost

--- In QuadtoneRIP@yahoogroups.com, "Roy Harrington" <roy@...> wrote:
>
> Hi Joost,
> 
> Actually its just the generic ones provided that don't have a simulate
> paper white.  Since I didn't have a particular paper in mind I
didn't put a

> white end in the profile.
> 
> The custom ones though all do have that capability.  You can easily
> create your own MattePaper profile using data such as:
> 
> Gray Lab A B
> 0    96  0 0
> 100  16 0 0
> 
> Fill in your Lab A & B values if you like.  Even if you don't have real
> measurements, experiment with some numbers for best match.

1) yes as far as the L luminosity values.  If you what hue that varies
over the range more points will be better.

2) always Perceptual Intent + Black Point Compensation

Roy

On Fri, Oct 17, 2008 at 11:52 PM, Joost Horsten <j.h.j.h@...> wrote:
> Hi Roy,
>
> That's extremely helpful! I played around a bit with it and see how I
> to apply it. Two questions though:
>
> 1) Assuming I have correctly linearized my prints curves, I need only
> the black point and the white point (and no points in between) as in
> your example, right?
>
> 2) What's in your experience the best rendering intent?
>
> Joost
>
> --- In QuadtoneRIP@yahoogroups.com, "Roy Harrington" <roy@...> wrote:
>>
>> Hi Joost,
>>
>> Actually its just the generic ones provided that don't have a simulate
>> paper white.  Since I didn't have a particular paper in mind I
> didn't put a
>> white end in the profile.
>>
>> The custom ones though all do have that capability.  You can easily
>> create your own MattePaper profile using data such as:
>>
>> Gray Lab A B
>> 0    96  0 0
>> 100  16 0 0
>>
>> Fill in your Lab A & B values if you like.  Even if you don't have real
>> measurements, experiment with some numbers for best match.
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>

Hi Roy!

Thanks for your answer...

That bring mutch light in my darkness!!! ;-)))

CU

Peter

--- In QuadtoneRIP@yahoogroups.com, "Roy Harrington" <roy@...> wrote:
>
> Hi Peter,
> 
> There are 3 create icc programs because some editing programs have
> restrictions and anomolies.
> 
> QTR-Create-ICC makes a grayscale ICC for printing and softproofing.
> Photoshop handles these and works great.
> 
> QTR-Create-ICC-RGB makes a functionally identical ICC but it's in
RGB format.
> Programs such as Lightroom, Qimage, and I think others don't work in
> grayscale so you need an RGB format ICC file.
> 
> QTR-Create-ICC-RGB-bpc is similar to the above but maps black-to-black
> directly.  This takes away softproofing with simulate-ink-black
capability.
> But some programs seem to get the "Black Point Compensation" wrong with
> the above ICC profiles so this ensures that everything is correct.
> 
> It's unfortunate that there seems to be variation of how different
programs
> handle B&W issue but that is the current state of things -- so
different ICCs
> are needed for them.
> 
> Roy
> 
> 
> On Wed, Oct 15, 2008 at 9:32 AM, grayscale2008 <pm2003@...> wrote:
> > Hi Joost!
> >
> > Thanks for your answer...
> >
> > Is there perhaps somebody who can answer my question 2???
> >
> > Or where can I find some more docu about creating curves?
> >
> > CU
> >
> > Peter
> >
> >
> > --- In QuadtoneRIP@yahoogroups.com, "Joost Horsten" <j.h.j.h@> wrote:
> >>
> >> --- 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
> >>
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
>

Hello Roy,

I hope you don't mind me saying so, but if I have analyzed things
correctly, the ICC profiles created by create-ICC have some anomalies
of their own. Maybe this accounts for some of the observed behavior.

ICC output profiles contain 6 tables: perceptual, relative
colorimetric and saturation intents, each in both directions. I'll
ignore the saturation intent tables because they have little to do
with photography. In the profiles constructed by create-ICC, the BtoA0
(perceptual Lab to printer) and AtoB1 (colorimetric printer to Lab)
tables are correct. These are the tables used for printing and soft
proofing in perceptual mode. However, their inverse tables (AtoB0 and
BtoA0) are *not* the inverse, but rather a copy of the same table in
the other mode: AtoB0 is a copy of AtoB1 and BtoA0 is a copy of BtoA1.

This breaks the use of the absolute and relative colorimetric
rendering intents. In addition, it makes it impossible to convert
*back* from the ICC profile space without affecting the look of the
image, because the inverse tables are not really inverse tables. The
QTR-Create-ICC-RGB-bpc application fixes the AtoB0 table (making an
invertible perceptual mapping), but changes the (correct) AtoB1 table,
thereby breaking soft proofing.

For more info, see the following post that I have written a little
over a month ago:
http://tech.groups.yahoo.com/group/QuadtoneRIP/message/7113

I think that the create-ICC application should be updated to create
AtoB0 and BtoA1 tables that are true inverse mappings of the BtoA0 and
AtoB1 tables, respectively. This would enable the use of the absolute
and relative colorimetric intents and my guess is that it would also
obviate the need for the separate create-ICC-RGB-bpc application.

Best Regards,
Simon


--- In QuadtoneRIP@yahoogroups.com, "Roy Harrington" <roy@...> wrote:
>
> Hi Peter,
> 
> There are 3 create icc programs because some editing programs have
> restrictions and anomolies.
> 
> QTR-Create-ICC makes a grayscale ICC for printing and softproofing.
> Photoshop handles these and works great.
> 
> QTR-Create-ICC-RGB makes a functionally identical ICC but it's in
RGB format.
> Programs such as Lightroom, Qimage, and I think others don't work in
> grayscale so you need an RGB format ICC file.
> 
> QTR-Create-ICC-RGB-bpc is similar to the above but maps black-to-black
> directly.  This takes away softproofing with simulate-ink-black
capability.
> But some programs seem to get the "Black Point Compensation" wrong with
> the above ICC profiles so this ensures that everything is correct.
> 
> It's unfortunate that there seems to be variation of how different
programs
> handle B&W issue but that is the current state of things -- so
different ICCs

> are needed for them.
> 
> Roy
> 
>