[scribus] pxd/x3 export : apparently contains RGB images

[eric hanuise]

>>> In PDF export>   colors>   target = printer
>>>        
>> Thanks. This option is greyed out when using pdf/x3 (but shows 'printer').
>>      
> That's because in PDF/X-3 an image is being included "as is" (RGB recommended,
> but CMYK is still possible). The conversion happens at the printer, using the
> embedded colour profile.
>
>    

Thanks, now it's quite clear.

before asking here, I searched the 'net and found several forum threads 
asking this question, and receiving no answer.
Maybe it would be interesting to add an option for this in the pdf x/3 
export dialog, disabled by default, that allows to convert all objects 
to cmyk using the output intent color profile.
My view is that while the standard accepts mixed rgb+cmyk, there are 
printers that complain about it, refuse to print it, or will charge 
extra for conversion, thus this could help the users of scribus facing 
such situations.
(with a nice help dialog stating that rgb should be supported in pdf/x3 
by the printer, but that the option to convert all to the cmyk profile 
is offered.)


>> When using another type of pdf (1.3 1.4 or 1.5) the prepress option does
>> not allow to specify the icc profile to be used as intent.
>>      
> Sure. As the caption says: "PDF/X-3 Output Intent".
>
>    
>> Will the profile defined in color management for printer be used ?
>> (I'm using 1.3.7 on ubuntu)
>>      
> Yes.
>
>    
Thanks again. While this may seem obvious and may seem to make sense, 
when you're struggling to define your workflow, it doesn't :)

>> How can I check the saved PDF to know which profile have actually been
>> used ?
>> Also, how can I check that the saved PDF does indeed only contain CMYK
>> objects and no RGB ? (Using tools available on linux)
>>      
> By opening the PDF file in a text editor (may take some time, though,
> depending on the speed of your CPU).
>    

I tried, there's a huge load of garbage, and a mention of the output 
intent profile at the document end, but no mention (at least in clear 
text) of the colorspaces or profiles of the individual elements in teh file.
What strings should I look for ?