Re: [Gimp-print-devel] 10 raw channels with photo and matte key

[Robert K. <rl...@al...>]

On 2/19/22 02:59, Andrew X wrote:
> But most of epson use 8ch printhead for 9 colors and switch mk/pk with inkselector. And I think with
> 10ch printhead we have a chance that all ten channels can have their own addresses for each channel.

It's possible, but if both matte and photo black currently work on their own on these printers, it's
not likely, since the ink sets for both use the same channel and subchannel numbers and the
cartridge is selected at initialization.  If matte black does *not* currently work on the P900 with
Gutenprint, then it probably will work.

> I'm not familiar with analyzing printer data, but I have p900 printer and can make any experiments
> with it if you tell me what to do and help to analyzing data to find Chanel addresses for mk/pk or
> to be sure it's not possible to use 10ch at one time.

The easiest way would be with parse-escp2.  However, the official drivers now likely all generate
ESCP/R, which is RGB data and hence there are no channels and subchannels available.

> Can you recommend channel/subchannel numbers to test first of all?

The channel is always 0 for black; I've found no exceptions.  For subchannel, 0 is almost always for
standard black, with the following exceptions:

* Some of the high volume 4-color printers (b500/c120 class): subchannel=4
* WorkForce 40-class: subchannel=6
* R800/R1800/R1900-class: subchannel=0 for photo black, 4 for matte black

Light black is always subchannel 1; light light black is always subchannel 3.

I would try 4, 6, 2, and 8 in that order for starters.  Then try the rest between 5 and 15
(subchannel is a 4 bit field).

> сб, 19 февр. 2022 г., 03:37 Robert Krawitz <rl...@al... <mailto:rl...@al...>>:
> 
>     On 2/16/22 18:19, Andrew X wrote:
>     > I know how it's work on p600/p800/3880 etc 8ch heads. On p700/900 printhead have 10 physical
>     > channels, print 10nozzle patterns and I want to manage all 10 channels in raw mode
> 
>     The only printers I know of where it might work are the R800/R1800/R1900.  All of the other printers
>     use the same code for matte and photo black ink, and the printer switches between them based on the
>     initialization code.
> 
>     > чт, 17 февр. 2022 г., 02:11 Michael Sweet via Gimp-print-devel
>     > <gim...@li... <mailto:gim...@li...>
>     <mailto:gim...@li... <mailto:gim...@li...>>>:
>     >
>     >     I believe the print head only supports 9 channels at a time and physically switches
>     between the
>     >     matte and photo black supply when you load the media (or at least that's how my P800
>     works... :)