QTR-Quadtone RIP

Hello,

I was searching for possible solution in this forum, but wasn't able to find any.

I am trying to create definition for K4+ inks from Paul in QTR 2.6.2.0 on windows using Xrite-810 on Epson Premium Semigloss paper.

I first all non-toner inks and created an linearized curve. All went very good. Of course tone of this set is rather warm. So I like to include curves for two toner inks.

After I did that and printed 21step for linearization I am getting error about " not constantly increasing".

Densities are as follows:

0.08	0.12	0.17	0.23	0.28	0.34	0.40	0.47	0.54	0.63	0.73	0.84	0.95	1.10	1.25	1.40	1.50	1.59	1.68	1.75	1.76

I think problem is somewhere else, but I have not enough experience to find out where. 

For toners I use the same curves which Paul has in his pdf file "QTR, 2200, 4K+Ccm Inkset, Matte BW 2880 Neutral Profile"

I appreciate any help, thank you.

All inks are from MIS and even I have Ebony in first K position I do not use it for this paper as the reflectivity of that ink is totally different that the rest of the inks.

pos1(K):  MIS Eboni, 
pos2(C):  MP-PK, 
pos3(M):  K4-LLK 
pos4(Y):  K4-LLLK
pos5(LC): K4-LLC
pos6(LM): K4-LM
pos7(LK): K4-LK 


Once more thanks for your help. I am not sure how including toner curves could come to this error.

--
richard vanek
www.richard-vanek.eu

Hi Richard,

The main issue is you have too much ink.  Notice the flat spot at the
top end -- 1.75 & 1.76
When you've added toner ink you saturated the paper & didn't get more density.
Otherwise it looks like you have a nice smooth curve.

The fix is simple -- reduce all the ink limits by at least 5% (I'd be
on the safe side and do 7%).

Roy

On Sat, May 16, 2009 at 1:57 AM, Richard Vanek <yahoo@...> wrote:
> Hello,
>
> I was searching for possible solution in this forum, but wasn't able to find any.
>
> I am trying to create definition for K4+ inks from Paul in QTR 2.6.2.0 on windows using Xrite-810 on Epson Premium Semigloss paper.
>
> I first all non-toner inks and created an linearized curve. All went very good. Of course tone of this set is rather warm. So I like to include curves for two toner inks.
>
> After I did that and printed 21step for linearization I am getting error about " not constantly increasing".
>
> Densities are as follows:
>
> 0.08    0.12    0.17    0.23    0.28    0.34    0.40    0.47    0.54    0.63    0.73    0.84    0.95    1.10    1.25    1.40    1.50    1.59    1.68    1.75    1.76
>
> I think problem is somewhere else, but I have not enough experience to find out where.
>
> For toners I use the same curves which Paul has in his pdf file "QTR, 2200, 4K+Ccm Inkset, Matte BW 2880 Neutral Profile"
>
> I appreciate any help, thank you.
>
> All inks are from MIS and even I have Ebony in first K position I do not use it for this paper as the reflectivity of that ink is totally different that the rest of the inks.
>
> pos1(K):  MIS Eboni,
> pos2(C):  MP-PK,
> pos3(M):  K4-LLK
> pos4(Y):  K4-LLLK
> pos5(LC): K4-LLC
> pos6(LM): K4-LM
> pos7(LK): K4-LK
>
>
> Once more thanks for your help. I am not sure how including toner curves could come to this error.
>
> --
> richard vanek
> www.richard-vanek.eu
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>

Hello Roy,

thank you for your quick response.
I was thinking that similar thing had happen.
I have decreased densities and now printing non-linearized 21step print. Than I need to wait for print to dry. I let you know how that all ends ;-)

One more question. I see on many posts here and also in pdfs from Paul Roark that color deviation of print are measured in L,a,b space. My Xrite produce RGB or visual densities. Can I use that in some way to evaluate temperature of my inks and use that to adjust toner's curves?

Thanks!

--
richard vanek
www.richard-vanek.eu

The density info is fine for the software.  You can use the color info
to evaluate hue.
Graphing the data in a spreadsheet is often helpful.
I'm not familiar with the details of the unit you have though.

Roy

On Sat, May 16, 2009 at 10:54 AM, Richard Vanek <yahoo@...> wrote:
> Hello Roy,
>
> thank you for your quick response.
> I was thinking that similar thing had happen.
> I have decreased densities and now printing non-linearized 21step print. Than I need to wait for print to dry. I let you know how that all ends ;-)
>
> One more question. I see on many posts here and also in pdfs from Paul Roark that color deviation of print are measured in L,a,b space. My Xrite produce RGB or visual densities. Can I use that in some way to evaluate temperature of my inks and use that to adjust toner's curves?
>
> Thanks!
>
> --
> richard vanek
> www.richard-vanek.eu
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>

Roy,

The linearization went perfect after I decrease ink load by 5%.
Thanks a lot for this tip.

Do you know how can I convert RGB densities to Lab, so I can compare 
easier different papers in 2D space?

QTR is excellent, thank you for it and I am going to buy it right a way!!!


--
richard vanek
www.richard-vanek.eu

> -----Original Message-----
> From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] On
> ...
> Do you know how can I convert RGB densities to Lab, so I can compare
> easier different papers in 2D space?
> 
> QTR is excellent, thank you for it and I am going to buy it right a way!!!
...
There is no way to convert RGB densities (e.g. from the Xrite-810) to LAB.

Tom Moore

Tom

I though so, but is there a way to be able to evaluate color shift based 
on RGB densities like it is possible by a and b in LAB?
I can put them in 3D but that would be rather difficult to compare I 
guess and to see if it is going warm or cold ;-)

Tom Moore wrote:
>> ...
>> Do you know how can I convert RGB densities to Lab, so I can compare
>> easier different papers in 2D space?
>>
> There is no way to convert RGB densities (e.g. from the Xrite-810) to LAB.
> 


--
richard vanek
www.richard-vanek.eu

Richard,

Don't do 3D, plot 3 lines R,G,B.  I'd think neutral they should
coincide or parallel.  If they
cross back and forth you probably have color variations.  It's mainly
a matter of trying
things and see if any help you decide what you like.

Roy

On Mon, May 18, 2009 at 10:59 AM, Richard Vanek <yahoo@...> wrote:
> Tom
>
> I though so, but is there a way to be able to evaluate color shift based
> on RGB densities like it is possible by a and b in LAB?
> I can put them in 3D but that would be rather difficult to compare I
> guess and to see if it is going warm or cold ;-)
>
> Tom Moore wrote:
>>> ...
>>> Do you know how can I convert RGB densities to Lab, so I can compare
>>> easier different papers in 2D space?
>>>
>> There is no way to convert RGB densities (e.g. from the Xrite-810) to LAB.
>>
>
>
> --
> richard vanek
> www.richard-vanek.eu
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>