QTR-Quadtone RIP

You can actually make your own QTR curves in QTR for K7 inks or for K6 inks. However, it is very challenging to make a QTR curve with seven shades and possibly as challenging with six.

The main difference between K7 curves and QTR made curves is the shape that you are limited to with the QTR Curve tool. We are able to increase resolution and smoothness and cross-overs by using our own toolset that produces curves with longer back ramps.

Probably, the easiest curves are made with only 3 or 4 inks in QTR. However, using more shades of ink increases the amount of possible gray separations. With 7 shades we are producing tens of thousands of gray levels. That may be overkill for some and a requisite for others once they have seen K7 output.

I would suggest that if you are going to experiment on your own - you install two complimentary K7 sets of ink such as the pure Carbon and the colder Selenium.

I would use a common black and the WN Shade 1 is exceedingly dense and dark and capable of both photo and matte printing. Install Carbon shades 2,4,5 and Selenium shades 2,4,5. You should be able to build one curve for Carbon quad set and use it for the Selenium quad set - and using QTR you can blend the two or split the two with the curves sliders. In this way, you give up fidelity for more toning options. But, you also gain the ability to make your own curves and have a split toning ink set or a blending ink set.  

In your LLK position you can keep the GO so that you can print the glossy prints without any gloss differential using the existing Piezography GO curve.

Your system will be the envy. :)  

I have made my own system like this and I can tell you it is beautiful to work with.

Jon Cone
Piezography


--- In QuadtoneRIP@yahoogroups.com, "michael43mathers" <mkmathers@...> wrote:
>
> 
> 
> --- In QuadtoneRIP@yahoogroups.com, "janbecket" <janbecket.net@> wrote:
> >
> > hello all,
> > Postings here have encouraged me to learn how to create profiles for my 4880, which currently has K7 inks and Photo Rag loaded. Seems like a good way to learn, since a profile for that ink/printer/paper combo comes bundled with QTR, and I can ultimately compare my profile with the bundled one. Good theory, at least.
> > 
> > I've followed Michael Mathers excellent QTR profile tutorial and have progressed through determining the MK ink limit (45) and then through assigning ink crossover limits to ink channels 2-7. However, in the K7 inkset I am using (Special Edition) channel #5 is far more dense than #4 or even #3. Effectively, there is no crossover with the previous channel. All of the other channels do have a crossover limit.
> > 
> > Since the ink limit for each channel references the previous channel, should I just set the ink limit for channel #5 (LC) at 100? (If one extrapolates, it is more like 150.)
> > 
> > Thanks in advance for any clarification!
> > 
> > -JB, Honolulu
> >
> 
> 
>   JB,
> 
> When you say K7 inks are you using the Piezographic K7 inks from the Ink Jet Mall?  And if you are, do you have them loaded in the slot sequence that they recommend?  eg slot 1 for shade 1, slot 2 for shade 2, slot 3 for shade 4, slot 4 for shade 7 etc.
> If you do, then as I understand from Jon Cone, you cannot make your own profiles.  They have some special ways and equipment to do it.  I use their K7 Special Edition inks and use their profile that come with QTR.  With the 4880 printer you can use any of the profiles for Epson printers in the series with  x880 designation.
> 
> Hope this helps.
> 
> Mike Mathers
>