Rag paper and ink consumption

[alifatemi]

Since I have to push more color intensity and contrast in soft proof to compensate for low Dmax of %100 cotton or rag papers, like Canson BFK or Hahnemuehle Rag papers, can we also conclude that printer uses more inks compare to Baryta or satan or high gloss for same print? Reading Jeff Schewe book, Digital Print, I have not encountered this or maybe I haven't noticed it in the book neither find it elsewhere.

[Chris233]

Perhaps your printer can run a status sheet of your previous jobs. Most wide format Epsons can print a list of previous job names along with the ink consumed in mL. I wouldn't use those figures as a lab control, but it should give you close enough measures to see how much ink you're laying down with various profiles.

This is through the printer driver measured by (I believe) nozzle firings, which would be independent of any profile or rip used to send the file to the machine.

[Geraldo Garcia]

(...)Baryta or satan(...)

The later must be a hell of a paper! 

[Ernst Dinkla]

There is a good document that describes HP Z media preset ink limits for different papers:
Z2100_and_Z3100_Working_with_other_commercially-available_paper_6.0.0.8.pdf
There are more HP Z documents that also describe the range of MK, PK, Grey, Light Grey inks used in Black Generation from all four to two or less if the paper coating can not handle high ink limits.
Yes, the quality matte art paper coatings get higher ink loads than gloss papers get.

Usually the ink limits in OEM media presets for OEM papers are made correctly and give you the highest Dmax and widest color gamut possible for that printer, paper and ink. Excessive ink amounts beyond that can result in loss of detail due to bleed/dotgain. If that bleed is acceptable you still may not get what you want: with pigment inks the Dmax usually does not increase, with dye inks it can increase. If the media presets are made properly the color gurus have fixed the ink limits per channel on Dmax for the Black, on max Chroma for the hues, on dot visibility for the partioning between LC>C, LM>M, on dot visibility for the substitution of composite grey to grey inks, on saturation where CMY mixes are replaced by additional hue inks like red, green and blue. All with an eye on limiting detail loss due to bleed which can happen over the entire tone range, not just in the black. To better that with just throwing more ink on the same paper is naïve. Gamut in total will usually not increase with higher loads of pigment inks but shift to a darker/richer gamut, the usual Advanced color ink settings in the driver do the same, a gamma increase that affect the mid tones more than the darkest tones and highlights.

In my experience with RIPs it has been difficult to get better color than the OEM media presets in the OEM RGB-device drivers deliver for the OEM media and similar third party media. If the subject allowed it I have made ink overloaded prints (on canvas mainly) that resembled silkscreen prints, color management and realism had little to do with that. The varnishing afterwards at least protected that surface. Printing twice on Photorag paper with an acceptable register was another approach to get that effect without too much bleeding on the boundaries (hard edge art). The surface of the pigment print even more vulnerable than with a single print run. Costly affair in the printing phase and in the prints returned by the customer.

--
Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
April 2014, 600+ inkjet media white spectral plots.

[Chris233]

VERY good information you posted Ernst

Printing twice on Photorag paper with an acceptable register was another approach to get that effect without too much bleeding on the boundaries (hard edge art). The surface of the pigment print even more vulnerable than with a single print run. Costly affair in the printing phase and in the prints returned by the customer.

You could check if your rip supports "multiple strike" printing. The print head runs the first (normal) print pass, then does the same pass again before moving on to the next advance. Registration will be much better/easier, but still not same as single strike printing. I've found lubricating the carriage rails helps reduce the vibrations causing most of those artifacts, though.