QTR-Quadtone RIP

Hi group:

I am developing my own curves and ICC profiles for QTR and Epson Velvet Fine Art for a 
Epson 2200 printer.  Everything looks great except my 95 and 100 wedges are identical.  Can 
anyone please tell me what is the best way to correct this problem.  When I printed the 
calibration page, I chose an ink limit of 65% black ...should this be lower.  I tried boosting the 
black and altering the shadow value neither of which made much difference.  

thanks

ron

--- In QuadtoneRIP@yahoogroups.com, "Ron Faris" <shutterbug52@...> 
wrote:

> I am developing my own curves and ICC profiles for QTR and Epson 
Velvet Fine Art for a 
> Epson 2200 printer.  Everything looks great except my 95 and 100 
wedges are identical.  Can 
> anyone please tell me what is the best way to correct this problem.  
When I printed the 
> calibration page, I chose an ink limit of 65% black ...should this be 
lower.  

That sounds the most logical approach to me. I suggest you go back to 
the first calibration page you printed (should have been with ink limit 
100%) and check again the ink limit you need to prevent the above. 
Might be 60% or 55%?

Success!

Joost

Ron

You don't say which inkset you are using. I have done a partial (warm/cool)
set of curves for Epson UC ink with VFA. This paper can definitely take a
lot more than 65% K ink for the UC matte. My curves have a default limit of
75% and a black boost of 95% and have good shadow separation. The issue I
never resolved was spattering of the black ink in the deep shadows.
Resolving it mean reducing the total K output and probably losing some dmax.
I lost interest when I started using UT7.

I can send you the curves and a curve evaluation spreadsheet if you are
interested. There's also a set of UCmk Velvet Fine Art curves in the files
section of the Yahoo QuadtoneRIP web site.

In addition to the K limit and Black Boost parameters, I have found the
Shadow and Gamma parameters on the Gray Curve panel can affect how your
curve behaves. Another thing you don't mention how you are linearizing the
curve (or even that you are). I assume you are, but the accuracy of your
density measurement device could also be a factor.

Hope this is useful

Tom Moore 

> -----Original Message-----
> From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] On
> Behalf Of Ron Faris
> Sent: Saturday, December 02, 2006 7:42 AM
> To: QuadtoneRIP@yahoogroups.com
> Subject: [QuadtoneRIP] blocked blacks
> 
> Hi group:
> 
> I am developing my own curves and ICC profiles for QTR and Epson Velvet
> Fine Art for a
> Epson 2200 printer.  Everything looks great except my 95 and 100 wedges
> are identical.  Can
> anyone please tell me what is the best way to correct this problem.  When
> I printed the
> calibration page, I chose an ink limit of 65% black ...should this be
> lower.  I tried boosting the
> black and altering the shadow value neither of which made much difference.
> 
> thanks
> 
> ron
>

Hi Tom

I am using the sepia toned NK7 inkset--my curves are linearized using  
printfix pro

thanks
ron

On Dec 2, 2006, at 4:10 PM, Tom Moore wrote:

> Ron
>
> You don't say which inkset you are using. I have done a partial  
> (warm/cool)
> set of curves for Epson UC ink with VFA. This paper can definitely  
> take a
> lot more than 65% K ink for the UC matte. My curves have a default  
> limit of
> 75% and a black boost of 95% and have good shadow separation. The  
> issue I
> never resolved was spattering of the black ink in the deep shadows.
> Resolving it mean reducing the total K output and probably losing  
> some dmax.
> I lost interest when I started using UT7.
>
> I can send you the curves and a curve evaluation spreadsheet if you  
> are
> interested. There's also a set of UCmk Velvet Fine Art curves in  
> the files
> section of the Yahoo QuadtoneRIP web site.
>
> In addition to the K limit and Black Boost parameters, I have found  
> the
> Shadow and Gamma parameters on the Gray Curve panel can affect how  
> your
> curve behaves. Another thing you don't mention how you are  
> linearizing the
> curve (or even that you are). I assume you are, but the accuracy of  
> your
> density measurement device could also be a factor.
>
> Hope this is useful
>
> Tom Moore
>
> > -----Original Message-----
> > From: QuadtoneRIP@yahoogroups.com  
> [mailto:QuadtoneRIP@yahoogroups.com] On
> > Behalf Of Ron Faris
> > Sent: Saturday, December 02, 2006 7:42 AM
> > To: QuadtoneRIP@yahoogroups.com
> > Subject: [QuadtoneRIP] blocked blacks
> >
> > Hi group:
> >
> > I am developing my own curves and ICC profiles for QTR and Epson  
> Velvet
> > Fine Art for a
> > Epson 2200 printer. Everything looks great except my 95 and 100  
> wedges
> > are identical. Can
> > anyone please tell me what is the best way to correct this  
> problem. When
> > I printed the
> > calibration page, I chose an ink limit of 65% black ...should  
> this be
> > lower. I tried boosting the
> > black and altering the shadow value neither of which made much  
> difference.
> >
> > thanks
> >
> > ron
> >
>
>
> 



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

Hi Ron
--- In QuadtoneRIP@yahoogroups.com, Ronald Faris <shutterbug52@...> wrote:
>
> Hi Tom
> 
> I am using the sepia toned NK7 inkset--my curves are linearized using  
> printfix pro
> 
Well that renders most of my previous comments irrelevant. Here are a
few more suggestions:

In the past, I have compared my limits and other parameters (e.g.
black boost) with those of other curves for the same printer&ink/
different papers and same printer&paper/different ink to get an idea
if I'm in the right ball park. Although the Cone suppled K7 curves
don't have qidf files, you can get an idea by using the display curve
selection in QTRgui (right click in the Curve Selection box).

To create a greater slope near the shadow end of your curve before it
is linearized you can reduce the black limit and increase the black
boost. That pushes out the high ink load to the deeper shadows. Once
you linearize, however, the curve will be brought back to the the
"standard" form the so- called ideal curve. If that is not creating
enough shadow separation for you when you print, you can adjust the
Gamma and Shadow adjustments in QTRgui to increase the shadow separation.

> thanks
> ron
 Good luck
Tom Moore

Tom:

Thanks for all your suggestions..I'm on a mac so I don't use the  
QTRgui version..
I have great seperation of the blacks in my linearized curve, it is  
only when
I then use that curve to print the wedges again and create my icc  
profile t
the problem is when i now use my curve and icc profile together that the
blacks are blocking up, I've tried lowering my ink limit from 65% to  
55% when I print
the ink seperation page and then relineazing etc, but the problem  
still persist when I
create and use the new icc profile...I'm still not sure why this is  
happening

ron


On Dec 2, 2006, at 11:57 PM, Tom Moore wrote:

> Hi Ron
> --- In QuadtoneRIP@yahoogroups.com, Ronald Faris <shutterbug52@...>  
> wrote:
> >
> > Hi Tom
> >
> > I am using the sepia toned NK7 inkset--my curves are linearized  
> using
> > printfix pro
> >
> Well that renders most of my previous comments irrelevant. Here are a
> few more suggestions:
>
> In the past, I have compared my limits and other parameters (e.g.
> black boost) with those of other curves for the same printer&ink/
> different papers and same printer&paper/different ink to get an idea
> if I'm in the right ball park. Although the Cone suppled K7 curves
> don't have qidf files, you can get an idea by using the display curve
> selection in QTRgui (right click in the Curve Selection box).
>
> To create a greater slope near the shadow end of your curve before it
> is linearized you can reduce the black limit and increase the black
> boost. That pushes out the high ink load to the deeper shadows. Once
> you linearize, however, the curve will be brought back to the the
> "standard" form the so- called ideal curve. If that is not creating
> enough shadow separation for you when you print, you can adjust the
> Gamma and Shadow adjustments in QTRgui to increase the shadow  
> separation.
>
> > thanks
> > ron
> Good luck
> Tom Moore
>
>
> 



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

--- In QuadtoneRIP@yahoogroups.com, "Ron Faris" <shutterbug52@...> wrote:
> I am developing my own curves and ICC profiles for QTR and Epson
Velvet Fine Art for a 
> Epson 2200 printer.  Everything looks great except my 95 and 100
wedges are identical.  Can 
> anyone please tell me what is the best way to correct this problem.
 When I printed the 
> calibration page, I chose an ink limit of 65% black ...should this
be lower.  I tried boosting the 
> black and altering the shadow value neither of which made much
difference.  

I use an i1 spectrophotometer to help set the ink limit.  Between 70
and 100% ink limit, the i1 readings indicate that there is clipping or
even reversal for the matte black wedges.  At 70% ink limit, it's
still very difficult to visually distinguish between the 95 and 100%
wedges, but the i1 readings show a gradient.

I then use the 70% ink limit and go through linearization, after which
all the individual wedges are visible.

Ronald Faris wrote:
> Tom:
> 
> Thanks for all your suggestions..I'm on a mac so I don't use the  
> QTRgui version..
> I have great seperation of the blacks in my linearized curve, it is  
> only when
> I then use that curve to print the wedges again and create my icc  
> profile t
> the problem is when i now use my curve and icc profile together that the
> blacks are blocking up, I've tried lowering my ink limit from 65% to  
> 55% when I print
> the ink seperation page and then relineazing etc, but the problem  
> still persist when I
> create and use the new icc profile...I'm still not sure why this is  
> happening
> 
> ron
> 
I've recently had the same experience with icc profiles. I've never used 
them with qtr before but thought I'd try them. All they did was make 
everything slightly darker and the shadows blocked up. If your qtr curve 
is well linearised and your happy with the output I really wouldn't mess 
with it by putting an ICC profile on top.

Howard

--- In QuadtoneRIP@yahoogroups.com, Ronald Faris <shutterbug52@...> wrote:
>
> Tom:
> 
> Thanks for all your suggestions..I'm on a mac so I don't use the  
> QTRgui version..

I'm sure the shadow/gamma feature I referred to is part of the RIP and
not just QTRgui. I just don't know how to access it on the Mac.

> I have great seperation of the blacks in my linearized curve, it is  
> only when
> I then use that curve to print the wedges again and create my icc  
> profile t
> the problem is when i now use my curve and icc profile together that the
> blacks are blocking up, I've tried lowering my ink limit from 65% to  
> 55% when I print
> the ink seperation page and then relineazing etc, but the problem  
> still persist when I
> create and use the new icc profile...I'm still not sure why this is  
> happening

Well, perhaps the problem lies in how you are using the ICC profile
rather than the curve itself. I can't help you as to how to use ICC
profiles in the Mac environment. It's probably just like printing in
colour with a profile, but I'm not sure. Perhaps others can help. Does
the softproof show blocked up shadows. Can you print without using the
ICC profile to see what effect it has.

> 
> ron
> 
...

Tom