QTR-Quadtone RIP

Howard,
The document includes some image captures of the linearization curves that do not paste 
well into this text area. That is why I did the PDF and found that I could not link it. So I 
uploaded into the file area.

I have also read the mini tutorial for MAC profiling. It appears that I am doing the same 
thing he describes just somewhat different sequence. I guess the best proof is that the 
prints look good.

Regards,
David
--- In QuadtoneRIP@yahoogroups.com, Howard Shaw <glassman@...> wrote:
>
> Hi David
> 
> I'd be happy to help but you appear to be using a Mac and I am a Windows 
> user. Although the principles are the same the detailed procedures for 
> curve creation are quite different.
> 
> There is another document in the files section which is specifically for 
> the mac and might be useful - QTR mini Tutorial on Curves.rtf
> 
> Hopefully a mac user can step in and help out. Why don't you post the 
> text of your pdf into an email to make it easier for people to respond.
> 
> regards
> Howard
> 
> 
> dmwket wrote:
> > Howard,
> > The delay was so that I could do a profiling process for Brilliant Museum Silver Gloss 
> > White using the process as I understand it based on your comments as well as the 
> > documentation included with QTR.
> > 
> > 
> > I am including a PDF document in which I describe the process. Hopefully this will 
provide 
> > sufficent information for you to determine if the process is valid or, if flawed what I 
> > should do to improve it.
> > 
> > /Users/DMWMBP/Desktop/QTR Profiling 10.5.2.pdf
> > 
> > I am happy to email you the word file if this would be more useful. Let me know.
> > 
> > I am happy to edit the process description and share it more widely once I am sure it 
is 
> > valid.
> > 
> > Regards,
> > David
> > 
> > --- In QuadtoneRIP@yahoogroups.com, Howard Shaw <glassman@> wrote:
> >>
> >> Sounds like you might possibly be confusing the settings for ink limit & 
> >> ink density?
> >> 
> >> Density should alway be 100 for the black ink but the limit should be 
> >> the level in the initial 100% calibration that gives you the best dmax 
> >> (there are exceptions such as where the limit is set lower but restored 
> >> with a higher black boost figure but don't worry about that at this stage).
> >> 
> >> Paste your qidf file into an email if you'd like me to have a look.
> >> 
> >> regards
> >> Howard
> >> 
> >> 
> >> dmwket wrote:
> >> > Howard,
> >> > Thanks for the information.
> >> > I found that when I tried to set the ink limit below 100% for the black, then the 
step 
> > wedge 
> >> > did not print at all.
> >> > 
> >> > For example, if the best Dmax was the 95% wedge and I set 95 as the black limit, 
then 
> >> > when printing the step wedge, the 100% wedge was just an outline. Also, all the 
> > numeric 
> >> > text next to the steps were also just an outline.
> >> > 
> >> > That's what led me to the conclusion that the black ink limit had to be set to 100 
in 
> > all 
> >> > cases and that the LK limit was used to set the point when K ink was used rather 
than 
> > the 
> >> > LK ink.
> >> > 
> >> > There are two or more places in the profile text file that have ink limit setting. 
> > Perhaps 
> >> > this is what is causing me the confusion.
> >> > 
> >> > Which settings are used to limit the total black ink flow to optimize Dmax?
> >> > 
> >> > thanks again for your insights.
> >> > 
> >> > David
> >> > 
> >> > --- In QuadtoneRIP@yahoogroups.com, Howard Shaw <glassman@> wrote:
> >> >>
> >> >> David
> >> >> 
> >> >> No, the calibration process should be done for each printer/ink/paper 
> >> >> combination. Different papers can take different amounts of ink and the 
> >> >> main purpose of the calibration is to guage the level of black ink which 
> >> >> provides the best dmax as well as the 'crossover' points for the black & 
> >> >> grey inks.
> >> >> 
> >> >> Printing the initial 100% calibration will give you the full range from 
> >> >> 5%-100% coverage. Dmax can actually decline with overinking and the best 
> >> >> dmax patch will almost certainly not be the 100% one.
> >> >> 
> >> >> My experience shows that, even using the Media Type of Matte Paper, 
> >> >> there are no papers, matt or gloss, that can take anything like the 
> >> >> amount of ink deposited in the 100% patch at the 100% calibration limit 
> >> >> at 2880dpi. The Matte paper setting therefore provides more than enough 
> >> >> latitude in terms of quantity of ink deposited.
> >> >> 
> >> >> Media Type may determine other factors (?platen gap ?drop size) that 
> >> >> might be factors but the evidence is inconclusive. Hopefully more people 
> >> >> will reply to the other David's thread in this regard.
> >> >> 
> >> >> regards
> >> >> Howard
> >> >> 
> >> >> --
> >> >> Howard Shaw
> >> >> www.howardshaw.org
> >> >> 
> >> >> dmwket wrote:
> >> >> > Howard,
> >> >> > It is my understanding from reading the material that the Ink Separation 
> > calibration is 
> >> > a 
> >> >> > printer specific, not paper specific calibration.
> >> >> > 
> >> >> > I did that calibration before starting the per paper profiling I described.
> >> >> > 
> >> >> > It is important to remember that that has to be accomplished as well. Thanks 
for 
> >> > pointing 
> >> >> > it out.
> >> >> > 
> >> >> > What drove me to doing the detailed profiling I described here is the lack of 
Dmax 
> >> > with 
> >> >> > the default matte paper selection even after doing the Separation calibration.
> >> >> > 
> >> >> > Regards,
> >> >> > David
> >> >> > 
> >> >> > 
> >> >> > --- In QuadtoneRIP@yahoogroups.com, Howard Shaw <glassman@> wrote:
> >> >> >>
> >> >> >> This method may work if the best black ink density for the new paper 
> >> >> >> matches that of the paper whose existing profile you use.
> >> >> >> 
> >> >> >> However a better way to optimise dmax and take out some of the guesswork 
> >> >> >> is to standardise on one paper setting & resolution and print one of the 
> >> >> >> ink separation tifs in calibration mode. See the file 'QuadToneRIP User 
> >> >> >> Guide.pdf' in the qtr folder for more details.
> >> >> >> 
> >> >> >> Howard
> >> >> >> 
> >> >> >> 
> >> >> >> dmwket wrote:
> >> >> >> > Alan,
> >> >> >> > Linearization is done on a per paper basis.
> >> >> >> > 
> >> >> >> > It is the profile used by QTR for that paper.
> >> >> >> > 
> >> >> >> > Based on experimentation and reading here on this forum I arrived at the 
> >> > following 
> >> >> >> > process;
> >> >> >> > 
> >> >> >> > 1) Select an existing profile text file that approximates the paper you want 
to 
> >> > profile 
> >> >> > and 
> >> >> >> > delete the Linearization line at the end of the file and save with a unique 
> > name.
> >> >> >> > 
> >> >> >> > 2) find the best Dmax by printing 100% black squares with several paper 
> > settings 
> >> > i.e. 
> >> >> >> > Premium Gloss Photo Paper, Premium Luster Photo Paper, etc. at 1440 as 
well 
> > as 
> >> >> > 2880 
> >> >> >> > using the file you created in 1 for the curve.
> >> >> >> > 
> >> >> >> > I positioned the ink swatch on the paper by clicking center image off and 
then 
> >> > setting 
> >> >> > a 
> >> >> >> > margin to create a row of swatches at the various setting.
> >> >> >> > 
> >> >> >> > These samples are all printed with No Color Management set in the printer 
> > dialog.
> >> >> >> > 
> >> >> >> > This is tedious but important. I let the samples dry for about 2 hours 
before 
> >> > reading 
> >> >> > them 
> >> >> >> > with my Spyder Spectrometer.
> >> >> >> > 
> >> >> >> > 3) Once the best Dmax paper, resolution setting is found. use that paper 
and 
> >> >> > resolution to 
> >> >> >> > print the 21 X 4 step wedge using the curve created in 1.
> >> >> >> > 
> >> >> >> > 4) Let the test print dry for a minimum 2 hours, over night is optimum, 
then 
> > read 
> >> > it 
> >> >> > and do 
> >> >> >> > the linearization.
> >> >> >> > 
> >> >> >> > 5) Copy the Linearization line from the text file and paste it into the file 
you 
> > made 
> >> > in 
> >> >> > 1 
> >> >> >> > above and save the file as your curve file for the paper.
> >> >> >> > 
> >> >> >> > 6) Copy the file into the printer profiles folder and "install the printer".
> >> >> >> > 
> >> >> >> > 7) Once the curve is installed I save a preset for QTR that has the paper 
> > selection, 
> >> >> >> > resolution setting and curve. I name the preset to reflect what paper it is 
to 
> >> > simplify 
> >> >> > my 
> >> >> >> > printing.
> >> >> >> > 
> >> >> >> > 
> >> >> >> > Trust this helps.
> >> >> >> > 
> >> >> >> > There may be a better way to do this that someone more experienced can 
> > offer.
> >> >> >> > 
> >> >> >> > Have fun learning QTR --- the B&W prints it produces are great.
> >> >> >> > 
> >> >> >> > Regards,
> >> >> >> > David
> >> >> >> > 
> >> >> >> > --- In QuadtoneRIP@yahoogroups.com, "handyman856" <avr@> wrote:
> >> >> >> >>
> >> >> >> >> Is linearization done on a 'per printer' basis, done once with any
> >> >> >> >> paper for a given printer, or is done 'per paper', and part of the
> >> >> >> >> profiling process of each paper?
> >> >> >> >> 
> >> >> >> >> =Alan R.
> >> >> >> >>
> >> >>
>