[Scribus] color gamut

[PLinnell]

Salut Florence,

On Thursday 27 April 2006 10:49, Florence Gaillaguet wrote:
> Hi,
>
> I have chosen 5 colors in a Pantone booklet, called my printer to
> get the CMYK values and created them with Scribus. A red triangle
> has appeared in the color menu : does this mean that the color are
> out of gamut ? 

Possibly. Possibly not.  These are a *warning*. The ICC specs do not 
define exactly how this works, so it is a 'best guess' based on the 
printing profile. The other variable is paper density and brightness. 
High gloss paper often has better gamut, as it can absorb more ink 
per sq/cm 


> What are the consequences of that ?

If you are printing CMYK, the ink combo might be outside of a given 
profile's gamut and depending on the rendering choice, there could be 
what we call gamut compression, where two close but not matching 
shades are merged into one. 

When printing images, you could lose detail in shadows or certain 
shades may not have the same vividness or deepness.

> Is it just a problem with my color management settings (ECI rvg &
> Iso Coated) ?

None at all. Just make sure Scribus is using a monitor profile for 
your monitor, not a generic RGB one.

>
> These are the CMYK :
> Dark red : 0 95 100 2
> Dark green : 34 0 81 71
> yellow : 0 18 100 0
> orange 0 42 100 7

Plugging these numbers in with Fogra-27 coated shows no warnings, but 
I think the getting the exact deep green and *exact* shade of red 
might be tricky. 

Using similar shades on a project coated stock did not pose a problem 
and I was very pleased with the results. The deep green was well 
saturated and the red was really really close.


>
> Thank you for your help
> Florence
Hope that helps,

Peter