Re: Photo Print Quality issue Canon G2000 series

Sounds great, I will give these recommendations a try! Your input is
greatly appreciated (especially given we have a new baby and we were trying
to print photos :) )

Wishing you a happy new year.

On Wed, Dec 30, 2020 at 5:36 AM Protea Wines Japan <[email protected]>
wrote:

> On Wed, Dec 30, 2020 at 7:20 PM Jonathan Ing <[email protected]>
> wrote:
> >
> > Hi Gernot,
> >
> > Thanks for this wonderful explanation - I have no background in tuning
> drivers before so this makes a LOT of sense! One question I have is then is
> there any resource or guide for CUPS density controls? For example, if you
> see x, y or z, increase or decrease this parameter?
>
> Hi Jonathan,
> Not really, that is general CUPS information, I guess searches are
> your best bet for what people have been doing for their particular
> purposes.
> As I wrote, it is a matter of extensive experimentation to work out
> per media type at least, and most likely per resolution mode (used for
> that media), what density corrections are required for each ink for
> different hue, saturation, and value for each colour, and combination
> of colours. You could start with a strip of black ink printing evenly
> from 0% to 100% intensity, and see if you can get an output that
> matches this. Some areas might need more careful tuning.
> Then go on to cyan, then magenta, and finally yellow, which is hardest to
> see.
>
> PS quick addendum, the plus Glossy II can use the other 2 photo modes
> as well, the mode one I listed is solely useable by plusPhoto II
> though.
>
> Best regards,
> Gernot Hassenpflug
>
> > Thanks!
> >
> >
> > On Wed, Dec 30, 2020 at 4:57 AM Protea Wines Japan <[email protected]>
> wrote:
> >>
> >> On Wed, Dec 30, 2020 at 12:20 AM Jonathan Ing <[email protected]>
> wrote:
> >>>
> >>> Hi, I am using the gutenprint v 5.3.3-4 on Ubuntu 20.04-1 and I notice
> that when printing photos (I am using 4x6 glossy, photo mode) and pictures
> have a low bitrate look to them... almost pixelated. I have set DPI to max
> 600x600 and nothing seems to help. Not sure if this is a potential bug?
> >>
> >>
> >> Hello,
> >> I am sure photo printing will not be good without some serious tuning
> of densities in CUPS, since the Canon driver does not include any
> calibration of colours.
> >> However, maybe you can get better results if I explain the process,
> what you are saying about resolution is not really how it works.
> >>
> >> Firstly, the Canon printheads only have resolutions of 300dpi or 600dpi
> (some have a single mode that is at 1200dpi).
> >> So "setting resolution to X dpi" is not what determines the quality.
> >> The firmware uses the physical printhead resolution, multi-pass
> printing and complex algorithms making use of the available physical inks,
> to print at some "effective resolution".
> >> The above process, and/or the possible quality, are different for each
> media type.
> >>
> >> Thus, when you select a resolution, you are not seeing a simple "X dpi"
> name for the resolution,
> >> what you see is a "resolution mode" name, such as "High quality (600
> DPI)", for example.
> >> Each media type has several possible resolution modes associated with
> it, and hints are given in the drop-down, so that users do not attempt to
> use, say, plain media modes, with photo media, or vice versa.
> >> If a resolution mode is chosen that the firmware does not know about
> for a particular media type, the printer will generally not print.
> >>
> >> So to prevent non-printing, if a non-compatible mode is selected in the
> Canon driver, then there is a forced selection to a similar quality mode
> accepted by the media.
> >> As a result, depending on the other options apart from media type
> (e.g., double-sided printing), you might not be printing with the mode you
> think you selected.
> >> The only way to be sure is to check the debug logs (setting them up in
> the CUPS interface).
> >>
> >> The G1000, G2000, G3000 share a common driver, with the following
> resolution modes available:
> >>
> >> A. For plain media
> >>
> >> 600x600 DPI HIGH
> >> 600x600 DPI
> >> 300x300 DPI
> >>
> >> B. For plus Glossy II only
> >>
> >> 600x600 DPI PHOTO HIGHEST plus Glossy II
> >>
> >> C. For other photo media
> >>
> >> 600x600 DPI PHOTO HIGH
> >> 600x600 DPI PHOTO
> >>
> >> D. For envelope and hagaki (postcard) media
> >>
> >> 600x600 DPI HIGH (Env/Hagaki)
> >> 600x600 DPI (Env/Hagaki)
> >>
> >> If you are trying one of the photo media resolution modes, and it is of
> poor quality, the tuning of the density of individual inks is probably way
> off.
> >> Tuning is a lot of experimental effort, but you can try with the CUPS
> density controls for the different channels to see if you can improve
> matters.
> >>
> >> Best regards,
> >> Gernot Hassenpflug
>
>
>
> --
> Protea Wines Japan
> Tel: 070-5550-9076
> https://www.proteawines.jp
>

_______________________________________________
Gimp-print-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/gimp-print-devel