On Sun, Mar 8, 2009 at 11:20 AM, Sven Neumann wrote:
> I think you are missing the bigger picture here. Channels are not only
> about saved selections. If they were, we should indeed declare then as
> such. But channels are also used for simulating spot colors and as such
> they are much more closely related to the color components that are
> shown at the top of the dialog. There are more interesting things that
> can be done with channels. Unfortunately this is not very well covered
> in the GIMP documentation (the old manual by the Kylanders was better in
> this regard). That's why it is even more important that we keep this
> close to the Photoshop channels dialog. Then users can at least benefit
> from the documentation that exists for PS.
I dug up a copy of this manula, and discovered a couple things after
playing with channels in 2.6.4 and 2.6.1 on Ubuntu.
In the instructions, it states:
Open the Channels tab and create a new channel. In the New Channel
Options dialog, set this channel to 100% Fill Opacity. Click the black color
swatch to access the Color Selection dialog, and choose a nice color (this will
be the first plate to be printed). Name the channel “navy blue” or the
on what color you chose. Click on the OK button.
Paste (right-click|Edit|Paste) the image into this channel.
It seems you can no longer paste into a channel. You have to take a
greyscale copy and drag it from the layer panel to the channel panel.
I also tried to duplicate a couple of PS n-tone tutorials, like this
I discovered that they can be duplicated in gimp with a few
changes...namely, the channel has to be inverted, and the curves must
be adjusted "backward" (i.e black on the left).
I was able to get some good success (I think) of a tritone with this method:
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