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Re: [SLUG] Lenovo wins $150m NSW schools deal or April Fools joke?

2009/4/2 Erik de Castro Lopo <mle+slug@xxxxxxxxxxxxx>:
> Ben wrote:
>> GIMP and Inkscape can't do CMYK,
> Does this not do it for Gimp?
>    http://my.opera.com/area42/blog/gimp-cmyk

from that link:

How its works:
* Open your RGB image in Gimp via "File > Open"
* Start Seperate+ "<Image Window> > Image > Seperate > Seperate"
* Setup the profiles, may as source "Adobe 1998" and as destination
profile "Euroscala V2"
* Press OK, an image with 4 layers is created
* Each layer represents a color channel of CMYK
* Now save the image as CMYK Tiff at "<Image Window> > Image >
Seperate > Save..."

That is really, really not an acceptable implementation of CMYK. It's
the kind of thing that could be applied as a filter afterwards. It
doesn't let you work in CMYK with any kind of ease, you still work in
RGB and then do some kind of hideous conversion that would be almost
impossible to fine tune.

The point of CMYK is that you create stuff in the appopriate colours:

My printing recommends the following:
* Black text: 100%K, 0% all others
* Black backgrounds: 100%K, 30%C, 0% others

RGB gets converted to CMY(Cyan, Magenta, Yellow)(with no K(Black) channel).

This leads to imperfect blacks in printing, and 3x the ink being
dumped to form black leads to smearing, drying issues etc.
Text ends up with fuzzy colour speckles around it too.

The GIMP plugin will not resolve these issues as every part of the
image would have to be hand tuned after being created, which is really
not practical.

> and this for inkscape (0.47):
>    http://my.opera.com/area42/blog/inkscape-cmyk

0.47 is not released as stable yet. Even then the CMYK is only just
coming, so there could be bugs with it, and it's only for PDF export,
not for other export types, which are safer for sending to printer,
especially when you start doing things like embedding rasters inside
PDFs, which any vaguely sophisticated document will have.

Also, I think it would be easy to assume that the embedded rasters
would have issues when it comes to CMYK as they are a whole other
issue, so it will be some time before things are running properly

>> If you want to campaign for open source, then probably try to get some
>> government money thrown towards open source development, rather than
>> try to push things that are inferior to the other market offerings.
> Schools is one area where it actually doesn't need to be as good as
> the rest of the world (ie lots of schools still have computers running
> win2k), but where cheaper is definitely a win.
> Erik
> --
> ----------------------------------------------------------------------
> Erik de Castro Lopo
> http://www.mega-nerd.com/
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