Printer color calibration tech specifics of result

[dgillilan]

Hi,
Does anyone know technically what the color calibration of a printer does in refining a media type, as opposed to developing an icc profile?
I am thinking that it  simply applies to a given media type, the characteristics of ink absorption and color reading measurements with the spectro, as opposed to developing an icc profile which is only applied to one specific paper name and not media type.
Thank you, Debra

[Ernst Dinkla]

Calibration brings back the printer output to a standard as specified by the manufacturer. This calibration can be per media (for example iPF8400, HP Z models) or more general and then based on one specific media type (older iPF models) but used by all the media presets after calibration. Linearisation of the ink channels can be part or the main function of the calibration but does not have to be an essential function of the calibration. Theoretically the regular calibration of the printer/media should keep the original ICC printer profile usable for much longer periods and make job repeats identical in output. In best case multiple printers of the same model should give identical prints after calibration for one paper quality while using the same ICC printer profile.

Calibration systems will not all behave the same in my opinion. It may be limited to linearising each ink channel between the maximum ink load and the paper white but not bring the maximum ink load or max density/chroma to a specific number. It can be based on density measurements with a densitometer (including the color channels, Canon iPF models) or on spectral measurements with a spectrometer (HP Z models). In best case but probably not used in practice on our printers, the calibration should be done with a spectrometer, set the maximum ink loads per channel to a manufacturer specified density/chroma number and linearise the channels between that number and paper white. Proofing papers should be within strict standards for their paper white so that side is covered too in the print proofing shops.

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Met vriendelijke groet, Ernst

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

[dgillilan]

Thank you Ernst, that fully answers my question.
I have color calibrated my Canon ipf 6400 for several media types and have developed custom media configuration settings for several papers and developed icc profiles with my i1, and I have done color calibration on my Canon Pro-1 (pigment, 12 inks) for several media types, and have custom icc profiles for it with my i1 also.

Thanks again, Debra

[digitaldog]

Calibration should put a device in an idealized condition and keep it that way should it drift, change it's behavior. Not all calibration however is handling that idealized condition, it depends on a number of factors. Once a device is calibrated and consistent, an ICC profile simply reflects that condition. Profiles without ideal calibration but that are consistent are not ideal. Profiles without calibration where a device is altering it's behavior is worthless.