QTR-Quadtone RIP

Since the Yahoo search is not the most efficient, I hope to ask this basic question:

How do you print using icc from QTRgui?  

I have been successful with the Create ICC program while printing on Mac but since I am now 
running bootcamp and Windows, how do I go about this with QTRgui?

Should I Assign Profile to the file and then print?  Or should I Convert to Profile?  

A bit confused at the moment.  Thanks to all in advance.

JoeM

Hi Joe.
You need to convert to profile before printing.

Regards
Duane



--- In QuadtoneRIP@yahoogroups.com, "joemulligan_68"
<joemulligan_68@...> wrote:
>
> Since the Yahoo search is not the most efficient, I hope to ask this
basic question:
> 
> How do you print using icc from QTRgui?  
> 
> I have been successful with the Create ICC program while printing on
Mac but since I am now 
> running bootcamp and Windows, how do I go about this with QTRgui?
> 
> Should I Assign Profile to the file and then print?  Or should I
Convert to Profile?  

> 
> A bit confused at the moment.  Thanks to all in advance.
> 
> JoeM
>

From what I'm seeing so far, I think it's best to just use the ICC profiles
for soft-proofing and not printing. I'm finding that printing an image using
the "QTR Gray Lab" profile yields better results than using a Create-ICC
generated profile with perceptual intent. The latter lightens the print
noticeably, and really kills the DMAX of the print (dropping it from 1.6 to
1.3 in the case of my custom curve for Hahnemuhle Photo Rag that I'm
currently working on).
 
I've been meaning to post a discussion about this and will try do so in the
next few days. First I want to finish tweaking my custom curve and do a bit
more testing/measuring.
 
Jeff
 


  _____  

From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] On
Behalf Of dlruckus
Sent: Wednesday, August 23, 2006 12:37 PM
To: QuadtoneRIP@yahoogroups.com
Subject: [QuadtoneRIP] Re: Printing with ICC profiles



Hi Joe.
You need to convert to profile before printing.

Regards
Duane

--- In QuadtoneRIP@ <mailto:QuadtoneRIP%40yahoogroups.com> yahoogroups.com,
"joemulligan_68"
<joemulligan_68@...> wrote:
>
> Since the Yahoo search is not the most efficient, I hope to ask this
basic question:
> 
> How do you print using icc from QTRgui? 
> 
> I have been successful with the Create ICC program while printing on
Mac but since I am now 
> running bootcamp and Windows, how do I go about this with QTRgui?
> 
> Should I Assign Profile to the file and then print? Or should I
Convert to Profile? 

> 
> A bit confused at the moment. Thanks to all in advance.
> 
> JoeM
>

Hi Jeff,

If you are seeing a drop in dMax using the ICC profile, the profile 
conversion is probably being
done incorrectly.  It sounds like RelCol conversion instead of 
Perceptual.

I can't tell whether you are on a PC or Mac but Photoshop often 
defaults to
Relative Colormetric conversion rather than Perceptual Intent.   Be 
sure to double check that you
are using Perceptual and using Black Point Compensation.

Roy

On Wednesday, August 23, 2006, at 11:01  AM, Jeff Kohn wrote:

> From what I'm seeing so far, I think it's best to just use the ICC 
> profiles for soft-proofing and not printing. I'm finding that printing 
> an image using the "QTR Gray Lab" profile yields better results than 
> using a Create-ICC generated profile with perceptual intent. The 
> latter lightens the print noticeably, and really kills the DMAX of the 
> print (dropping it from 1.6 to 1.3 in the case of my custom curve for 
> Hahnemuhle Photo Rag that I'm currently working on).
>  
> I've been meaning to post a discussion about this and will try do so 
> in the next few days. First I want to finish tweaking my custom curve 
> and do a bit more testing/measuring.
>  
> Jeff
>  
>
<image.tiff>
>
> From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] 
> On Behalf Of dlruckus
> Sent: Wednesday, August 23, 2006 12:37 PM
> To: QuadtoneRIP@yahoogroups.com
> Subject: [QuadtoneRIP] Re: Printing with ICC profiles
>
>
> Hi Joe.
> You need to convert to profile before printing.
>
> Regards
> Duane
>
> --- In QuadtoneRIP@yahoogroups.com, "joemulligan_68"
> <joemulligan_68@...> wrote:
> >
> > Since the Yahoo search is not the most efficient, I hope to ask this
> basic question:
> >
> > How do you print using icc from QTRgui?
> >
> > I have been successful with the Create ICC program while printing on
> Mac but since I am now
> > running bootcamp and Windows, how do I go about this with QTRgui?
> >
> > Should I Assign Profile to the file and then print? Or should I
> Convert to Profile?
> >
> > A bit confused at the moment. Thanks to all in advance.
> >
> > JoeM
> >
>
> 
-
Roy Harrington
roy@...
Black & White Photo Gallery
http://www.harrington.com

Hello Jeff.
 Actualy, if everything is calibrated and profiled properly, and you
use the ICC profile for softproofing, it probably doesn't matter what
you use as the working space. You are visually adjusting the file for
what the output will be anyway. The point of the softproof is to be
WYSIWYG onscreen. Since Roy used Lab as the basis for linearization of
the printer curves, it isn't a surprise that it might print ok
directly from Gray Lab. The match should be as good as the printers
linearization is.

 Why do you use perceptual intent with B&W since nothing can possibly
be out of gamut? (Not  a criticism, just curious.)

Regards
Duane



--- In QuadtoneRIP@yahoogroups.com, "Jeff Kohn" <jkohn@...> wrote:
>
> From what I'm seeing so far, I think it's best to just use the ICC
profiles
> for soft-proofing and not printing. I'm finding that printing an
image using
> the "QTR Gray Lab" profile yields better results than using a Create-ICC
> generated profile with perceptual intent. The latter lightens the print
> noticeably, and really kills the DMAX of the print (dropping it from
1.6 to
> 1.3 in the case of my custom curve for Hahnemuhle Photo Rag that I'm
> currently working on).
>  
> I've been meaning to post a discussion about this and will try do so
in the
> next few days. First I want to finish tweaking my custom curve and
do a bit
> more testing/measuring.
>  
> Jeff
>  
> 
> 
>   _____  
> 
> From: QuadtoneRIP@yahoogroups.com
[mailto:QuadtoneRIP@yahoogroups.com] On
> Behalf Of dlruckus
> Sent: Wednesday, August 23, 2006 12:37 PM
> To: QuadtoneRIP@yahoogroups.com
> Subject: [QuadtoneRIP] Re: Printing with ICC profiles
> 
> 
> 
> Hi Joe.
> You need to convert to profile before printing.
> 
> Regards
> Duane
> 
> --- In QuadtoneRIP@ <mailto:QuadtoneRIP%40yahoogroups.com>
yahoogroups.com,

> "joemulligan_68"
> <joemulligan_68@> wrote:
> >
> > Since the Yahoo search is not the most efficient, I hope to ask this
> basic question:
> > 
> > How do you print using icc from QTRgui? 
> > 
> > I have been successful with the Create ICC program while printing on
> Mac but since I am now 
> > running bootcamp and Windows, how do I go about this with QTRgui?
> > 
> > Should I Assign Profile to the file and then print? Or should I
> Convert to Profile? 
> > 
> > A bit confused at the moment. Thanks to all in advance.
> > 
> > JoeM
> >
>

Hello Roy.
I should have asked you about why perceptual intent makes a difference
with the icc on B&W instead of asking Jeff. I understand why with full
color but am missing something with low gamut inks. Could you explain
a bit?

Regards
Duane


--- In QuadtoneRIP@yahoogroups.com, Roy Harrington <roy@...> wrote:
>
> Hi Jeff,
> 
> If you are seeing a drop in dMax using the ICC profile, the profile 
> conversion is probably being
> done incorrectly.  It sounds like RelCol conversion instead of 
> Perceptual.
> 
> I can't tell whether you are on a PC or Mac but Photoshop often 
> defaults to
> Relative Colormetric conversion rather than Perceptual Intent.   Be 
> sure to double check that you
> are using Perceptual and using Black Point Compensation.
> 
> Roy
> 
> On Wednesday, August 23, 2006, at 11:01  AM, Jeff Kohn wrote:
> 
> > From what I'm seeing so far, I think it's best to just use the ICC 
> > profiles for soft-proofing and not printing. I'm finding that
printing 
> > an image using the "QTR Gray Lab" profile yields better results than 
> > using a Create-ICC generated profile with perceptual intent. The 
> > latter lightens the print noticeably, and really kills the DMAX of
the 
> > print (dropping it from 1.6 to 1.3 in the case of my custom curve for 
> > Hahnemuhle Photo Rag that I'm currently working on).
> >  
> > I've been meaning to post a discussion about this and will try do so 
> > in the next few days. First I want to finish tweaking my custom curve 
> > and do a bit more testing/measuring.
> >  
> > Jeff
> >  
> >
> <image.tiff>
> >
> > From: QuadtoneRIP@yahoogroups.com
[mailto:QuadtoneRIP@...m] 

> > On Behalf Of dlruckus
> > Sent: Wednesday, August 23, 2006 12:37 PM
> > To: QuadtoneRIP@yahoogroups.com
> > Subject: [QuadtoneRIP] Re: Printing with ICC profiles
> >
> >
> > Hi Joe.
> > You need to convert to profile before printing.
> >
> > Regards
> > Duane
> >
> > --- In QuadtoneRIP@yahoogroups.com, "joemulligan_68"
> > <joemulligan_68@> wrote:
> > >
> > > Since the Yahoo search is not the most efficient, I hope to ask this
> > basic question:
> > >
> > > How do you print using icc from QTRgui?
> > >
> > > I have been successful with the Create ICC program while printing on
> > Mac but since I am now
> > > running bootcamp and Windows, how do I go about this with QTRgui?
> > >
> > > Should I Assign Profile to the file and then print? Or should I
> > Convert to Profile?
> > >
> > > A bit confused at the moment. Thanks to all in advance.
> > >
> > > JoeM
> > >
> >
> > 
> -
> Roy Harrington
> roy@...
> Black & White Photo Gallery
> http://www.harrington.com
>

--- In QuadtoneRIP@yahoogroups.com, Roy Harrington <roy@...> wrote:
>
> Hi Jeff,
> 
> If you are seeing a drop in dMax using the ICC profile, the profile 
> conversion is probably being
> done incorrectly.  It sounds like RelCol conversion instead of 
> Perceptual.
> 
> I can't tell whether you are on a PC or Mac but Photoshop often 
> defaults to
> Relative Colormetric conversion rather than Perceptual Intent.   Be 
> sure to double check that you
> are using Perceptual and using Black Point Compensation.

I'll have to do some more testing to confirm what I saw, I suppose 
it's possible I got the test files mixed up but I don't think so. 
What I did was print the 21-step test file in QImage three times, 
once using "Gray Lab RGB" as the  output profile, once using the QTR-
Create-ICC-RGB generated profile with rel-col, and once using the 
profile with perceptual intent. Then I measured all three with Eye 
One and graphed the results:

http://www.pbase.com/image/65715318

If you think about it, this makes sense. I see no reason for rel-col 
to boost the shadows because it's basically going to do a direct 
mapping and then just clip any "out-of-gamut" colors, which in this 
case means dark tones that can't repro on matte paper. It's 
perceptual intent that will try to "fit" the image into the target 
profile by compressing the gamut.

This test was done using a custom curve I created for HPR, and the 
curve had been linearized. 

What's interesting, is that looking at the chart it would appear that 
rel-col is the clear choice. But what I found when printing a real 
image was that the shadows were too blocked up, due to the fact that 
anything below L*=17 was getting mapped to the same color. So the 
gray-lab approach seems to work best for me at the moment (with matte 
papers at least), although it does lighten the image just a bit.

Like I said, I plan to do some more investigation on this. I'll 
repeat the test and make sure I didn't get the samples mixed up. I 
also plan to do the same test with photo-black on Innova F-Type paper.

--- In QuadtoneRIP@yahoogroups.com, "dlruckus" <dlruckus@...> wrote:
>
> Hello Jeff.
> Actualy, if everything is calibrated and profiled properly, and you
> use the ICC profile for softproofing, it probably doesn't matter what
> you use as the working space. You are visually adjusting the file for
> what the output will be anyway. The point of the softproof is to be
> WYSIWYG onscreen. Since Roy used Lab as the basis for linearization of
> the printer curves, it isn't a surprise that it might print ok
> directly from Gray Lab. The match should be as good as the printers
> linearization is.


If my file is actually grayscale, I agree. But I often work in RGB even
for monochrome images (for instance if I want the web version to be
slightly toned).  So I wanted to see which ICC profile I should convert
to in QImage to get the best results when printing, as well as see if
this workflow would be any different from converting to gray-lab in
Photoshop and then saving that as a tiff to print in QTR.



> Why do you use perceptual intent with B&W since nothing can possibly
> be out of gamut? (Not a criticism, just curious.)


Gamut isn't just about color. Can your printer reproduce L* values from
zero all the way to 100? Mine can't, especially on matte paper where the
darkest I can get is about L=17.

You know the more I think about this, it seems like maybe the linearization
within QTR is already a kind of perceptual rendering, since it re-maps the
curve to given you a smooth, even transition from black to white (0 to 100).
In that case maybe by converting to the ICC profile with perceptual intent,
in a way you're double-profiling?
 

Jeff
 


  _____  

From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] On
Behalf Of Roy Harrington
Sent: Thursday, August 24, 2006 11:45 AM
To: QuadtoneRIP@yahoogroups.com
Subject: Re: [QuadtoneRIP] Re: Printing with ICC profiles



Hi Jeff,

If you are seeing a drop in dMax using the ICC profile, the profile 
conversion is probably being
done incorrectly. It sounds like RelCol conversion instead of 
Perceptual.

I can't tell whether you are on a PC or Mac but Photoshop often 
defaults to
Relative Colormetric conversion rather than Perceptual Intent. Be 
sure to double check that you
are using Perceptual and using Black Point Compensation.

Roy

On Wednesday, August 23, 2006, at 11:01 AM, Jeff Kohn wrote:

> From what I'm seeing so far, I think it's best to just use the ICC 
> profiles for soft-proofing and not printing. I'm finding that printing 
> an image using the "QTR Gray Lab" profile yields better results than 
> using a Create-ICC generated profile with perceptual intent. The 
> latter lightens the print noticeably, and really kills the DMAX of the 
> print (dropping it from 1.6 to 1.3 in the case of my custom curve for 
> Hahnemuhle Photo Rag that I'm currently working on).
>  
> I've been meaning to post a discussion about this and will try do so 
> in the next few days. First I want to finish tweaking my custom curve 
> and do a bit more testing/measuring.
>  
> Jeff
>  
>
<image.tiff>
>
> From: QuadtoneRIP@ <mailto:QuadtoneRIP%40yahoogroups.com> yahoogroups.com
[mailto:QuadtoneRIP@ <mailto:QuadtoneRIP%40yahoogroups.com> yahoogroups.com]

> On Behalf Of dlruckus
> Sent: Wednesday, August 23, 2006 12:37 PM
> To: QuadtoneRIP@ <mailto:QuadtoneRIP%40yahoogroups.com> yahoogroups.com
> Subject: [QuadtoneRIP] Re: Printing with ICC profiles
>
>
> Hi Joe.
> You need to convert to profile before printing.
>
> Regards
> Duane
>
> --- In QuadtoneRIP@ <mailto:QuadtoneRIP%40yahoogroups.com>
yahoogroups.com, "joemulligan_68"
> <joemulligan_68@...> wrote:
> >
> > Since the Yahoo search is not the most efficient, I hope to ask this
> basic question:
> >
> > How do you print using icc from QTRgui?
> >
> > I have been successful with the Create ICC program while printing on
> Mac but since I am now
> > running bootcamp and Windows, how do I go about this with QTRgui?
> >
> > Should I Assign Profile to the file and then print? Or should I
> Convert to Profile?
> >
> > A bit confused at the moment. Thanks to all in advance.
> >
> > JoeM
> >
>
> 
-
Roy Harrington
roy@harrington. <mailto:roy%40harrington.com> com
Black & White Photo Gallery
http://www.harringt <http://www.harrington.com> on.com

The linearization inside of QTR is to make the driver produce 
consistent, smooth gradients.
It's also crucial to the Tone Blending so that density variations don't 
occur.
While the ICC profiling resembles this linearization, it provides color 
management info to
match screen to print.  Without it the embedded profile of the image 
would be ignored for
printing but not for the display.  It also allows to CM system to map 
the idealized gray working
space into the actual dMax and dMin in the way that gives the best 
"perceptual" feel of the print.

The issues of using various intents and black pt comp are not as well 
defined by the ICC standard
as you might think.  Lots of details are left to the implementer.    
The basic math for QTR ICC
profiles is based on perceptual intent and bpc as published by Adobe 
(not ICC btw).
Take a swatch of pure black and try various combinations of Convert to 
Profile and you'll see
that some don't maintain the pure black.   My recommendation on 
Perceptual and BPC is based
on trying various ways and seeing that this is the most consistent.

Roy

On Thursday, August 24, 2006, at 08:41  PM, Jeff Kohn wrote:

> You know the more I think about this, it seems like maybe the 
> linearization within QTR is already a kind of perceptual rendering, 
> since it re-maps the curve to given you a smooth, even transition from 
> black to white (0 to 100). In that case maybe by converting to the ICC 
> profile with perceptual intent, in a way you're double-profiling?
>  
>
> Jeff
>  
>
<image.tiff>
>
> From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] 
> On Behalf Of Roy Harrington
> Sent: Thursday, August 24, 2006 11:45 AM
> To: QuadtoneRIP@yahoogroups.com
> Subject: Re: [QuadtoneRIP] Re: Printing with ICC profiles
>
>
> Hi Jeff,
>
> If you are seeing a drop in dMax using the ICC profile, the profile
> conversion is probably being
> done incorrectly. It sounds like RelCol conversion instead of
> Perceptual.
>
> I can't tell whether you are on a PC or Mac but Photoshop often
> defaults to
> Relative Colormetric conversion rather than Perceptual Intent. Be
> sure to double check that you
> are using Perceptual and using Black Point Compensation.
>
> Roy
>
> On Wednesday, August 23, 2006, at 11:01 AM, Jeff Kohn wrote:
>
> > From what I'm seeing so far, I think it's best to just use the ICC
> > profiles for soft-proofing and not printing. I'm finding that 
> printing
> > an image using the "QTR Gray Lab" profile yields better results than
> > using a Create-ICC generated profile with perceptual intent. The
> > latter lightens the print noticeably, and really kills the DMAX of 
> the
> > print (dropping it from 1.6 to 1.3 in the case of my custom curve for
> > Hahnemuhle Photo Rag that I'm currently working on).
> >  
> > I've been meaning to post a discussion about this and will try do so
> > in the next few days. First I want to finish tweaking my custom curve
> > and do a bit more testing/measuring.
> >  
> > Jeff
> >  
> >
> <image.tiff>
> >
> > From: QuadtoneRIP@yahoogroups.com 
> [mailto:QuadtoneRIP@yahoogroups.com]
> > On Behalf Of dlruckus
> > Sent: Wednesday, August 23, 2006 12:37 PM
> > To: QuadtoneRIP@yahoogroups.com
> > Subject: [QuadtoneRIP] Re: Printing with ICC profiles
> >
> >
> > Hi Joe.
> > You need to convert to profile before printing.
> >
> > Regards
> > Duane
> >
> > --- In QuadtoneRIP@yahoogroups.com, "joemulligan_68"
> > <joemulligan_68@...> wrote:
> > >
> > > Since the Yahoo search is not the most efficient, I hope to ask 
> this
> > basic question:
> > >
> > > How do you print using icc from QTRgui?
> > >
> > > I have been successful with the Create ICC program while printing 
> on
> > Mac but since I am now
> > > running bootcamp and Windows, how do I go about this with QTRgui?
> > >
> > > Should I Assign Profile to the file and then print? Or should I
> > Convert to Profile?
> > >
> > > A bit confused at the moment. Thanks to all in advance.
> > >
> > > JoeM
> > >
> >
> >
> -
> Roy Harrington
> roy@harrington.com
> Black & White Photo Gallery
> http://www.harrington.com
>
>
-
Roy Harrington
roy@...
Black & White Photo Gallery
http://www.harrington.com

Ah yes, of course. Sorry. Too late & too little thought given.
Thanks.

Duane



--- In QuadtoneRIP@yahoogroups.com, "jkohn_home" <jkohn@...> wrote:

>
> Gamut isn't just about color. Can your printer reproduce L* values from
> zero all the way to 100? Mine can't, especially on matte paper where the
> darkest I can get is about L=17.
>