last one:

(peter) yahvuu wrote:

>>> there's one thing i don't understand, may be a misconception:
>>> why is it necessary to have separate modes for editing the RGB data
>>> and the plates?
>> mainly because creating art on a RGB monitor, to be used on
>> many media, is not the same _activity_ as bringing this art to
>> _one_ particular printing press.
>> also, it is better when the art itself is separated from the  
>> adaptation of
>> it for one press run.
> ah, that helps. So it is deprecated to create single-ink 'light blue  
> text'
> directly on  the 'light blue' plate, as the text would then not be  
> known to
> be part of the artwork.

yes, but then I would not stop anybody from doing that. sometimes it  
be necessary like applying a ghost image in matte varnish on top
of a glossy full color image: it may be most efficient to do the
matte varnish plate from scratch by itself...

> Can you give an outline how the print color for that text will be  
> specified?

specify a color (pantone, RAL, etc.) for the plate.

> The RGB color isn't useful here and the text layer can't be accessed  
> while
> the press projection is pulled over, IIUC. So each artwork layer  
> will have
> a custom color separation setting resp. color mapping?

no the other way around, each plate gets "mixed" from channels + layers.
I know this is not simple nor solved at the moment. since the plate
is a momochrome drawable, we need to look at the text layer and  
per pixel "how much is there", where 'how much' can be a choice or
combination of the (inverse of) value/lightness/alpha/layer opacity,
and perhaps more.

>>> Is it correct that there's no 'live preview' of the effects that RGB
>>> manipulations have on the plates?
>> if that is really needed by some users (see the two activities above
>> and also "no substitute for experience") then a second view of the
>> file (View->New view) can be run with the projection pulled down.
>> might be hard on the processor.
> Regarding the use-case of matching one color from a photo with a
> predetermined ink combination, i think this will be useful.

reading this again I am getting confused what you really mean here.

> yep, that's the desired effect here. For the single-ink text  
> example, a bit more
> than filling the light blue plate to 100% is required, though, as  
> the other
> plates have to be set to 0% for that area.

yeah, I realised that. must be part of the set-up to do that.

> My question is how and where such a layer->plate mapping will be  
> specified,
> for example when i want my text to be (0, 0, 50%, 50% ,0) on the  
> five plates.

well, plates 3 and 4 need to be set up (in the projection set-up) to  

0.5 * "the (inverse of) value/lightness/alpha/layer opacity"


         founder + principal interaction architect
             man + machine interface works
 : on interaction architecture

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