QTR-Quadtone RIP

after going through all the references I can find, it looks to me like the Photoshop curve import function in the Windows version with curve creation is the most straightforward, current, and viable approach to making unique toner setups..
Would you QTR experts here agree?
Thanks,
Tyler

Hi Tyler,

I think the answer to your question is yes, but ...

Having experimented over the last few months with HP-C6 aiming for neutral
and needing to warm it up in the 3/4 tones to achieve that, I got very
frustrated with the inflexibility of QTR to re-linearise after editing a
toning curve.

The problem is that you can add a toner as you describe below, but when you
linearise the tone curve will change and you can't edit it further, you can
only start again with a new tone curve. There is no way, I can see, to do
sequential linearizations in QTR and that's a real pain.

My solution was to write my own linearization program that takes a set of
QTR curves (actual ink values in Quad file) and linerarizes them. This let's
me edit a toner curve ink values (often manually in Excel) and relinearize
them again. It even allows me to look at the predicted re-linearized ab
curves before I print them and decide if I need to tweak them further.

Through testing this HP-C6 approach I also discovered that the QTR curve
model that doesn't use many overlapping inks, is suspectable to
posterization. I had a print that posterized and someone suggested is was
possibly a problem with QTR curve model.
So I created another curve model that was more like Cone's model where the
inks overlap much more and indeed the posterization problem was solved. BUT
the cost of this overlapping ink approach is reduced dmax. On Canon Rag 310
the dmax drops from L=15.3 to L=16 due to the other inks polluting the
darkest ink. So you've got to choose between the limitations of the two
approaches.

Learn't a lot about QTR in the last few months.

Mike




On 5 March 2010 23:06, tboleyyh <tyler@...> wrote:

>
>
> after going through all the references I can find, it looks to me like the
> Photoshop curve import function in the Windows version with curve creation
> is the most straightforward, current, and viable approach to making unique
> toner setups..
> Would you QTR experts here agree?
> Thanks,
> Tyler
>
>  
>


[Non-text portions of this message have been removed]

Mike, you are up to some very cool things, really impressive. Very interested in hearing about the ink.
I think I know what you mean regarding my question... I'd import a different toner curve based on tests, which requires another start linearization, and then the proportion of toner to grays in various tonal areas has changed from that which I had used to base the curve edit upon... round and round. That's ok, I accept that for this particular project, if I'm getting the picture.
Let us know how your work goes, really intriguing. Can you overlap progressively less moving down to the low end? So you have K only at 100%? Everything get's a bit jammed up down there and it's hard to control...
Tyler


--- In QuadtoneRIP@yahoogroups.com, Michael King <drmrking@...> wrote:

>
> Hi Tyler,
> 
> I think the answer to your question is yes, but ...
> 
> Having experimented over the last few months with HP-C6 aiming for neutral
> and needing to warm it up in the 3/4 tones to achieve that, I got very
> frustrated with the inflexibility of QTR to re-linearise after editing a
> toning curve.
> 
> The problem is that you can add a toner as you describe below, but when you
> linearise the tone curve will change and you can't edit it further, you can
> only start again with a new tone curve. There is no way, I can see, to do
> sequential linearizations in QTR and that's a real pain.
> 
> My solution was to write my own linearization program that takes a set of
> QTR curves (actual ink values in Quad file) and linerarizes them. This let's
> me edit a toner curve ink values (often manually in Excel) and relinearize
> them again. It even allows me to look at the predicted re-linearized ab
> curves before I print them and decide if I need to tweak them further.
> 
> Through testing this HP-C6 approach I also discovered that the QTR curve
> model that doesn't use many overlapping inks, is suspectable to
> posterization. I had a print that posterized and someone suggested is was
> possibly a problem with QTR curve model.
> So I created another curve model that was more like Cone's model where the
> inks overlap much more and indeed the posterization problem was solved. BUT
> the cost of this overlapping ink approach is reduced dmax. On Canon Rag 310
> the dmax drops from L=15.3 to L=16 due to the other inks polluting the
> darkest ink. So you've got to choose between the limitations of the two
> approaches.
> 
> Learn't a lot about QTR in the last few months.
> 
> Mike
> 
> 
> 
> 
> On 5 March 2010 23:06, tboleyyh <tyler@...> wrote:
> 
> >
> >
> > after going through all the references I can find, it looks to me like the
> > Photoshop curve import function in the Windows version with curve creation
> > is the most straightforward, current, and viable approach to making unique
> > toner setups..
> > Would you QTR experts here agree?
> > Thanks,
> > Tyler
> >
> >  
> >
> 
> 
> [Non-text portions of this message have been removed]
>

Tyler,

> Mike, you are up to some very cool things, really impressive. Very
> interested in hearing about the ink.
>
I like it more than I expected. Paul Roark has done all the hard work, I am
just standing on his shoulders. Works great in R1900. I am using18% Eboni as
toner in 3/4 tones.

> I think I know what you mean regarding my question... I'd import a
> different toner curve based on tests, which requires another start
> linearization, and then the proportion of toner to grays in various tonal
> areas has changed from that which I had used to base the curve edit upon...
> round and round. That's ok, I accept that for this particular project, if
> I'm getting the picture.
>
Yes that's exactly the issue, round and round we go and there is no way to
predict the outcome, though you can guesstimate better after the first
linearization.

>  Let us know how your work goes, really intriguing. Can you overlap
> progressively less moving down to the low end? So you have K only at 100%?
> Everything get's a bit jammed up down there and it's hard to control...
>
I am not sure,  I think not for maximum smoothness. So I may just generate
two curve sets one for maximum smoothness based on Cone style overlapping
ink curves and one for maximum dmax based on QTR curves.

Mike

>
> Tyler
>
>
> --- In QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com>,
> Michael King <drmrking@...> wrote:
> >
> > Hi Tyler,
> >
> > I think the answer to your question is yes, but ...
> >
> > Having experimented over the last few months with HP-C6 aiming for
> neutral
> > and needing to warm it up in the 3/4 tones to achieve that, I got very
> > frustrated with the inflexibility of QTR to re-linearise after editing a
> > toning curve.
> >
> > The problem is that you can add a toner as you describe below, but when
> you
> > linearise the tone curve will change and you can't edit it further, you
> can
> > only start again with a new tone curve. There is no way, I can see, to do
> > sequential linearizations in QTR and that's a real pain.
> >
> > My solution was to write my own linearization program that takes a set of
> > QTR curves (actual ink values in Quad file) and linerarizes them. This
> let's
> > me edit a toner curve ink values (often manually in Excel) and
> relinearize
> > them again. It even allows me to look at the predicted re-linearized ab
> > curves before I print them and decide if I need to tweak them further.
> >
> > Through testing this HP-C6 approach I also discovered that the QTR curve
> > model that doesn't use many overlapping inks, is suspectable to
> > posterization. I had a print that posterized and someone suggested is was
> > possibly a problem with QTR curve model.
> > So I created another curve model that was more like Cone's model where
> the
> > inks overlap much more and indeed the posterization problem was solved.
> BUT
> > the cost of this overlapping ink approach is reduced dmax. On Canon Rag
> 310
> > the dmax drops from L=15.3 to L=16 due to the other inks polluting the
> > darkest ink. So you've got to choose between the limitations of the two
> > approaches.
> >
> > Learn't a lot about QTR in the last few months.
> >
> > Mike
> >
> >
> >
> >
> > On 5 March 2010 23:06, tboleyyh <tyler@...> wrote:
> >
> > >
> > >
> > > after going through all the references I can find, it looks to me like
> the
> > > Photoshop curve import function in the Windows version with curve
> creation
> > > is the most straightforward, current, and viable approach to making
> unique
> > > toner setups..
> > > Would you QTR experts here agree?
> > > Thanks,
> > > Tyler
> > >
> > >
> > >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>  
>


[Non-text portions of this message have been removed]

Mike,
Glad to see you are still working on the HPC6. I have now installed these
inks into my 3800 and I am using QTR for printing using two curves. I have
tried to use HP just as a toner but have had the same issue with the
linearization of the curve the second time. I do not know how to solve this
issue without starting over. As for the 3800 I am having more problems with
banding on it than I did with my 1400 which never had any problems. I did
get some Tergitol but have not added it yet to see if it helps. Overall I am
still happy with the inks results and continue to work with them. If there
are others testing these inks I would like to hear of their results. 
Gary Wagner
www.garywagner.com 

-----Original Message-----
From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] On
Behalf Of Michael King
Sent: Saturday, March 06, 2010 7:05 AM
To: QuadtoneRIP@yahoogroups.com
Subject: Re: [QuadtoneRIP] Re: custom toner curve setups

Tyler,

> Mike, you are up to some very cool things, really impressive. Very
> interested in hearing about the ink.
>
I like it more than I expected. Paul Roark has done all the hard work, I am
just standing on his shoulders. Works great in R1900. I am using18% Eboni as
toner in 3/4 tones.

one more possibility Mike- have you thought of using the curve blending to help with this? I don't know your inkset, but if you don't need the blending in QTR for hue adjustment, you can use it to blend curves made with other parameter differences. For example, one curve might be made with huge overlaps, one medium, another none. Blend them so the highlights are 100% huge overlaps, mids medium, shadows none... or some such variation..
Just a thought, the main idea being that the blend options in the driver can be used in other creative ways than the hue variations for which they were intended...
You could even blend a tritone with a hextone.. for more complex dotwork, etc.. you get the idea..
Tyler

--- In QuadtoneRIP@yahoogroups.com, Michael King <drmrking@...> wrote:

>
> Tyler,
> 
> > Mike, you are up to some very cool things, really impressive. Very
> > interested in hearing about the ink.
> >
> I like it more than I expected. Paul Roark has done all the hard work, I am
> just standing on his shoulders. Works great in R1900. I am using18% Eboni as
> toner in 3/4 tones.
> 
> > I think I know what you mean regarding my question... I'd import a
> > different toner curve based on tests, which requires another start
> > linearization, and then the proportion of toner to grays in various tonal
> > areas has changed from that which I had used to base the curve edit upon...
> > round and round. That's ok, I accept that for this particular project, if
> > I'm getting the picture.
> >
> Yes that's exactly the issue, round and round we go and there is no way to
> predict the outcome, though you can guesstimate better after the first
> linearization.
> 
> >  Let us know how your work goes, really intriguing. Can you overlap
> > progressively less moving down to the low end? So you have K only at 100%?
> > Everything get's a bit jammed up down there and it's hard to control...
> >
> I am not sure,  I think not for maximum smoothness. So I may just generate
> two curve sets one for maximum smoothness based on Cone style overlapping
> ink curves and one for maximum dmax based on QTR curves.
> 
> Mike
> 
> >
> > Tyler
> >
> >
> > --- In QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com>,
> > Michael King <drmrking@> wrote:
> > >
> > > Hi Tyler,
> > >
> > > I think the answer to your question is yes, but ...
> > >
> > > Having experimented over the last few months with HP-C6 aiming for
> > neutral
> > > and needing to warm it up in the 3/4 tones to achieve that, I got very
> > > frustrated with the inflexibility of QTR to re-linearise after editing a
> > > toning curve.
> > >
> > > The problem is that you can add a toner as you describe below, but when
> > you
> > > linearise the tone curve will change and you can't edit it further, you
> > can
> > > only start again with a new tone curve. There is no way, I can see, to do
> > > sequential linearizations in QTR and that's a real pain.
> > >
> > > My solution was to write my own linearization program that takes a set of
> > > QTR curves (actual ink values in Quad file) and linerarizes them. This
> > let's
> > > me edit a toner curve ink values (often manually in Excel) and
> > relinearize
> > > them again. It even allows me to look at the predicted re-linearized ab
> > > curves before I print them and decide if I need to tweak them further.
> > >
> > > Through testing this HP-C6 approach I also discovered that the QTR curve
> > > model that doesn't use many overlapping inks, is suspectable to
> > > posterization. I had a print that posterized and someone suggested is was
> > > possibly a problem with QTR curve model.
> > > So I created another curve model that was more like Cone's model where
> > the
> > > inks overlap much more and indeed the posterization problem was solved.
> > BUT
> > > the cost of this overlapping ink approach is reduced dmax. On Canon Rag
> > 310
> > > the dmax drops from L=15.3 to L=16 due to the other inks polluting the
> > > darkest ink. So you've got to choose between the limitations of the two
> > > approaches.
> > >
> > > Learn't a lot about QTR in the last few months.
> > >
> > > Mike
> > >
> > >
> > >
> > >
> > > On 5 March 2010 23:06, tboleyyh <tyler@> wrote:
> > >
> > > >
> > > >
> > > > after going through all the references I can find, it looks to me like
> > the
> > > > Photoshop curve import function in the Windows version with curve
> > creation
> > > > is the most straightforward, current, and viable approach to making
> > unique
> > > > toner setups..
> > > > Would you QTR experts here agree?
> > > > Thanks,
> > > > Tyler
> > > >
> > > >
> > > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
> >  
> >
> 
> 
> [Non-text portions of this message have been removed]
>

Tyler, interesting idea. I will keep a more open mind as to how to leverage
the blending.

Txs,

Mike

On 6 March 2010 18:20, tboleyyh <tyler@tylerboley.com> wrote:

>
>
> one more possibility Mike- have you thought of using the curve blending to
> help with this? I don't know your inkset, but if you don't need the blending
> in QTR for hue adjustment, you can use it to blend curves made with other
> parameter differences. For example, one curve might be made with huge
> overlaps, one medium, another none. Blend them so the highlights are 100%
> huge overlaps, mids medium, shadows none... or some such variation..
> Just a thought, the main idea being that the blend options in the driver
> can be used in other creative ways than the hue variations for which they
> were intended...
> You could even blend a tritone with a hextone.. for more complex dotwork,
> etc.. you get the idea..
>
> Tyler
>
> --- In QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com>,
> Michael King <drmrking@...> wrote:
> >
> > Tyler,
> >
> > > Mike, you are up to some very cool things, really impressive. Very
> > > interested in hearing about the ink.
> > >
> > I like it more than I expected. Paul Roark has done all the hard work, I
> am
> > just standing on his shoulders. Works great in R1900. I am using18% Eboni
> as
> > toner in 3/4 tones.
> >
> > > I think I know what you mean regarding my question... I'd import a
> > > different toner curve based on tests, which requires another start
> > > linearization, and then the proportion of toner to grays in various
> tonal
> > > areas has changed from that which I had used to base the curve edit
> upon...
> > > round and round. That's ok, I accept that for this particular project,
> if
> > > I'm getting the picture.
> > >
> > Yes that's exactly the issue, round and round we go and there is no way
> to
> > predict the outcome, though you can guesstimate better after the first
> > linearization.
> >
> > > Let us know how your work goes, really intriguing. Can you overlap
> > > progressively less moving down to the low end? So you have K only at
> 100%?
> > > Everything get's a bit jammed up down there and it's hard to control...
> > >
> > I am not sure, I think not for maximum smoothness. So I may just generate
> > two curve sets one for maximum smoothness based on Cone style overlapping
> > ink curves and one for maximum dmax based on QTR curves.
> >
> > Mike
> >
> > >
> > > Tyler
> > >
> > >
> > > --- In QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com><QuadtoneRIP%
> 40yahoogroups.com>,
>
> > > Michael King <drmrking@> wrote:
> > > >
> > > > Hi Tyler,
> > > >
> > > > I think the answer to your question is yes, but ...
> > > >
> > > > Having experimented over the last few months with HP-C6 aiming for
> > > neutral
> > > > and needing to warm it up in the 3/4 tones to achieve that, I got
> very
> > > > frustrated with the inflexibility of QTR to re-linearise after
> editing a
> > > > toning curve.
> > > >
> > > > The problem is that you can add a toner as you describe below, but
> when
> > > you
> > > > linearise the tone curve will change and you can't edit it further,
> you
> > > can
> > > > only start again with a new tone curve. There is no way, I can see,
> to do
> > > > sequential linearizations in QTR and that's a real pain.
> > > >
> > > > My solution was to write my own linearization program that takes a
> set of
> > > > QTR curves (actual ink values in Quad file) and linerarizes them.
> This
> > > let's
> > > > me edit a toner curve ink values (often manually in Excel) and
> > > relinearize
> > > > them again. It even allows me to look at the predicted re-linearized
> ab
> > > > curves before I print them and decide if I need to tweak them
> further.
> > > >
> > > > Through testing this HP-C6 approach I also discovered that the QTR
> curve
> > > > model that doesn't use many overlapping inks, is suspectable to
> > > > posterization. I had a print that posterized and someone suggested is
> was
> > > > possibly a problem with QTR curve model.
> > > > So I created another curve model that was more like Cone's model
> where
> > > the
> > > > inks overlap much more and indeed the posterization problem was
> solved.
> > > BUT
> > > > the cost of this overlapping ink approach is reduced dmax. On Canon
> Rag
> > > 310
> > > > the dmax drops from L=15.3 to L=16 due to the other inks polluting
> the
> > > > darkest ink. So you've got to choose between the limitations of the
> two
> > > > approaches.
> > > >
> > > > Learn't a lot about QTR in the last few months.
> > > >
> > > > Mike
> > > >
> > > >
> > > >
> > > >
> > > > On 5 March 2010 23:06, tboleyyh <tyler@> wrote:
> > > >
> > > > >
> > > > >
> > > > > after going through all the references I can find, it looks to me
> like
> > > the
> > > > > Photoshop curve import function in the Windows version with curve
> > > creation
> > > > > is the most straightforward, current, and viable approach to making
> > > unique
> > > > > toner setups..
> > > > > Would you QTR experts here agree?
> > > > > Thanks,
> > > > > Tyler
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > > [Non-text portions of this message have been removed]
> > > >
> > >
> > >
> > >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>  
>


[Non-text portions of this message have been removed]

Hi Gary,

It was your print that set me down this path and I thank you for that.

Would be great to see another print from you in the exchange.
Will you get the time to participate again?

Cheers,

Mike

On 6 March 2010 15:32, Gary <gary@...> wrote:

>
>
> Mike,
> Glad to see you are still working on the HPC6. I have now installed these
> inks into my 3800 and I am using QTR for printing using two curves. I have
> tried to use HP just as a toner but have had the same issue with the
> linearization of the curve the second time. I do not know how to solve this
> issue without starting over. As for the 3800 I am having more problems with
> banding on it than I did with my 1400 which never had any problems. I did
> get some Tergitol but have not added it yet to see if it helps. Overall I
> am
> still happy with the inks results and continue to work with them. If there
> are others testing these inks I would like to hear of their results.
> Gary Wagner
> www.garywagner.com
>
> -----Original Message-----
> From: QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com> [mailto:
> QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com>] On
> Behalf Of Michael King
> Sent: Saturday, March 06, 2010 7:05 AM
> To: QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com>
> Subject: Re: [QuadtoneRIP] Re: custom toner curve setups
>
> Tyler,
>
> > Mike, you are up to some very cool things, really impressive. Very
> > interested in hearing about the ink.
> >
> I like it more than I expected. Paul Roark has done all the hard work, I am
> just standing on his shoulders. Works great in R1900. I am using18% Eboni
> as
> toner in 3/4 tones.
>
>  
>


[Non-text portions of this message have been removed]

Mike,
I hope to do another print for the exchange this year. I have also found it
to be very interesting and again want to thank Paul Roark for his work in
this area. Have you tried any of the Arches paper that Paul is suggesting? I
have done a few sheets but am still working on improving the results.
Best Wishes,
Gary Wagner

-----Original Message-----
From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] On
Behalf Of Michael King
Sent: Saturday, March 06, 2010 10:40 AM
To: QuadtoneRIP@yahoogroups.com
Subject: Re: [QuadtoneRIP] Re: custom toner curve setups

Hi Gary,

It was your print that set me down this path and I thank you for that.

Would be great to see another print from you in the exchange.
Will you get the time to participate again?

Cheers,

Mike
rms/

the downside being... if you really want highest possible linearity security, and blending your beautifully linearized curves leaves that a bit iffy.. you have to do the overall of any given settings combo with a real profile of the setup w/ settings. I have to do that for my StudioPrint setups that use spot channels as toners.
I made a 101 patch chart and text reference file for create ICC. The setup obviously has to be very well behaved in the first place so the profiler won't choke, but it works well. To even it out there are a few redundant patches at the dark end for averaging.
If you or anyone else here would like access to it let me know.
Tyler

--- In QuadtoneRIP@yahoogroups.com, Michael King <drmrking@...> wrote:

>
> Tyler, interesting idea. I will keep a more open mind as to how to leverage
> the blending.
> 
> Txs,
> 
> Mike
> 
> On 6 March 2010 18:20, tboleyyh <tyler@...> wrote:
> 
> >
> >
> > one more possibility Mike- have you thought of using the curve blending to
> > help with this? I don't know your inkset, but if you don't need the blending
> > in QTR for hue adjustment, you can use it to blend curves made with other
> > parameter differences. For example, one curve might be made with huge
> > overlaps, one medium, another none. Blend them so the highlights are 100%
> > huge overlaps, mids medium, shadows none... or some such variation..
> > Just a thought, the main idea being that the blend options in the driver
> > can be used in other creative ways than the hue variations for which they
> > were intended...
> > You could even blend a tritone with a hextone.. for more complex dotwork,
> > etc.. you get the idea..
> >
> > Tyler
> >
> > --- In QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com>,
> > Michael King <drmrking@> wrote:
> > >
> > > Tyler,
> > >
> > > > Mike, you are up to some very cool things, really impressive. Very
> > > > interested in hearing about the ink.
> > > >
> > > I like it more than I expected. Paul Roark has done all the hard work, I
> > am
> > > just standing on his shoulders. Works great in R1900. I am using18% Eboni
> > as
> > > toner in 3/4 tones.
> > >
> > > > I think I know what you mean regarding my question... I'd import a
> > > > different toner curve based on tests, which requires another start
> > > > linearization, and then the proportion of toner to grays in various
> > tonal
> > > > areas has changed from that which I had used to base the curve edit
> > upon...
> > > > round and round. That's ok, I accept that for this particular project,
> > if
> > > > I'm getting the picture.
> > > >
> > > Yes that's exactly the issue, round and round we go and there is no way
> > to
> > > predict the outcome, though you can guesstimate better after the first
> > > linearization.
> > >
> > > > Let us know how your work goes, really intriguing. Can you overlap
> > > > progressively less moving down to the low end? So you have K only at
> > 100%?
> > > > Everything get's a bit jammed up down there and it's hard to control...
> > > >
> > > I am not sure, I think not for maximum smoothness. So I may just generate
> > > two curve sets one for maximum smoothness based on Cone style overlapping
> > > ink curves and one for maximum dmax based on QTR curves.
> > >
> > > Mike
> > >
> > > >
> > > > Tyler
> > > >
> > > >
> > > > --- In QuadtoneRIP@yahoogroups.com <QuadtoneRIP%40yahoogroups.com><QuadtoneRIP%
> > 40yahoogroups.com>,
> >
> > > > Michael King <drmrking@> wrote:
> > > > >
> > > > > Hi Tyler,
> > > > >
> > > > > I think the answer to your question is yes, but ...
> > > > >
> > > > > Having experimented over the last few months with HP-C6 aiming for
> > > > neutral
> > > > > and needing to warm it up in the 3/4 tones to achieve that, I got
> > very
> > > > > frustrated with the inflexibility of QTR to re-linearise after
> > editing a
> > > > > toning curve.
> > > > >
> > > > > The problem is that you can add a toner as you describe below, but
> > when
> > > > you
> > > > > linearise the tone curve will change and you can't edit it further,
> > you
> > > > can
> > > > > only start again with a new tone curve. There is no way, I can see,
> > to do
> > > > > sequential linearizations in QTR and that's a real pain.
> > > > >
> > > > > My solution was to write my own linearization program that takes a
> > set of
> > > > > QTR curves (actual ink values in Quad file) and linerarizes them.
> > This
> > > > let's
> > > > > me edit a toner curve ink values (often manually in Excel) and
> > > > relinearize
> > > > > them again. It even allows me to look at the predicted re-linearized
> > ab
> > > > > curves before I print them and decide if I need to tweak them
> > further.
> > > > >
> > > > > Through testing this HP-C6 approach I also discovered that the QTR
> > curve
> > > > > model that doesn't use many overlapping inks, is suspectable to
> > > > > posterization. I had a print that posterized and someone suggested is
> > was
> > > > > possibly a problem with QTR curve model.
> > > > > So I created another curve model that was more like Cone's model
> > where
> > > > the
> > > > > inks overlap much more and indeed the posterization problem was
> > solved.
> > > > BUT
> > > > > the cost of this overlapping ink approach is reduced dmax. On Canon
> > Rag
> > > > 310
> > > > > the dmax drops from L=15.3 to L=16 due to the other inks polluting
> > the
> > > > > darkest ink. So you've got to choose between the limitations of the
> > two
> > > > > approaches.
> > > > >
> > > > > Learn't a lot about QTR in the last few months.
> > > > >
> > > > > Mike
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > On 5 March 2010 23:06, tboleyyh <tyler@> wrote:
> > > > >
> > > > > >
> > > > > >
> > > > > > after going through all the references I can find, it looks to me
> > like
> > > > the
> > > > > > Photoshop curve import function in the Windows version with curve
> > > > creation
> > > > > > is the most straightforward, current, and viable approach to making
> > > > unique
> > > > > > toner setups..
> > > > > > Would you QTR experts here agree?
> > > > > > Thanks,
> > > > > > Tyler
> > > > > >
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > > > [Non-text portions of this message have been removed]
> > > > >
> > > >
> > > >
> > > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
> >  
> >
> 
> 
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