Re: [Gimp-print-devel] Gutenprint and Epson Pro 7900

[Alvaro K. <ku...@gm...>]

I was thinking of doing a separate graphical application that edits the XML
for that purpose.

It is a very common issue on these EPSON large format printers. I've read
in numerous forums that Green or Orange channels clog up.

I believe if we document (outside Gutenprint but using Gutenprint, to not
disturb the project) and make an easy solution we could save printers from
going to waste.

On Mon, Feb 15, 2021 at 12:53 PM Walker Blackwell <
fo...@wa...> wrote:

> It really would be a pretty cool feature to allow for Channel remap
> changes right in the PPD . . .
>
> Best,
> Walker
>
>
> On Feb 15, 2021, at 8:34 PM, Alvaro Kuolas <ku...@gm...> wrote:
>
> To print 6 colors on EPSON Stylus Pro 7890 I need to use <InkName
> translate="text" name="PhotoCMYK" text="Six Color Photo" InkID="CcMmYK">
>
> To swap the Ink Channels on 7890 we need to modify the
> pro_ultrachrome_k3v.xml file.
>
> If I want to change the Yellow Color to Light Black I would need to change:
>
>    <channel name="standard_yellow" index="3">
>     <HueCurveParam name="YellowHueCurve"/>
>     <subchannel color="4" name="Yellow" text="Yellow" translate="text">
>      <ChannelDensityParam name="YellowDensity"/>
>     </subchannel>
>    </channel>
>
> To:
>
>    <channel name="standard_yellow" index="3">
>     <HueCurveParam name="YellowHueCurve"/>
>     <subchannel color="0" subchannel="1" name="Yellow" text="Yellow"
> translate="text">
>      <ChannelDensityParam name="YellowDensity"/>
>     </subchannel>
>    </channel>
>
>
> The color is the low 4 bits of the hex value; the subchannel is the high 4
> bits.
> So LightBlack has a hex value of 0x10 and Yellow has a hex value of 0x28.
>
> Well, That is in theory. I have searched this mailing list for all the
> bits I could find about this.
>
> Is this right? I am missing something?
>
> I could not test it yet because I do not have all the inks on the printer,
> I am waiting for them to be delivered.
>
> Meanwhile I am learning as much as I can from Gutenprint. I am trying to
> gather information as much as I can.
>
> When I finish this I will try to write a tutorial of sorts because this
> topic seems to surface from time to time in the mailing list.
>
> Thanks for your patience and good work!
>
> On Mon, Feb 15, 2021 at 5:24 AM Alvaro Kuolas <ku...@gm...> wrote:
>
>> I have a 7890 (same as 7900 but with 8 colors instead of 10: no Orange,
>> no Green channels).
>>
>> I have a busted Yellow Channel, and possibly the LLK as well.
>>
>> It is possible to make it print in 6 colors? Like CcMmYK ?
>>
>> I could reorder the channels as described in this thread, but, How to
>> make it behave like a 6 color printer?
>>
>> Thanks!
>>
> _______________________________________________
> Gimp-print-devel mailing list
> Gim...@li...
> https://lists.sourceforge.net/lists/listinfo/gimp-print-devel
>
>
> _______________________________________________
> Gimp-print-devel mailing list
> Gim...@li...
> https://lists.sourceforge.net/lists/listinfo/gimp-print-devel
>