cedric <[EMAIL PROTECTED]> writes:
> 1. Copy Visible does not copie visible, but the visible of layer
> aspect. Explanation : just deactivate a channel (R for exemple) the
> copy visible picture is the same as if they were all activated. Is
> there any way to overpass that ?
Well, you could try to improve the "Copy Visible" script. But perhaps
it should simply be renamed since "Copy Visible" is not exactly what
> 2. It seems that is is not possible to delete a primary channel
> (contextual menuitem is always grayed). What about if I want to do
> a 2-channel picture, particularly for 'professional' print ?
GIMP images are either gray or RGB. If you want to do duotone, the GUM
explains how to do that with GIMP.
> 4. I've used Decompose to CMYK to get a black channel and increase
> contrast on a document. But i've been surprise, because after doing
> the same in Adobe Photoshop, the black channels were different ? Is
> that normal ? What have I bas done, if any ?
There are an infinite amount of results for decomposing an RGB image
into CMYK. The conversion depends on the amount of black pullout as
well as on the properties of the printer, the inks and the paper that
is being used. The decompose plug-in takes a rather naive approach so
it is not surprising that you don't get the same result.
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