Hi! I'm having problems with Scribus, imported PDF's (and to a lesser extend with photos) and exporting a PDF to be printed by a printing company. The color and overall image quality is greatly reduced in this process. I have looked into the color management documentation and can't really understand why scribus behaves the way it does. It may be I have misunderstood some basic color management concepts (since this is a new field for me), but right now I think color management is not needed at all in my case. Can anyone shed some light on my problem?
I deduce that I don't need any color management, since: - all the graphical material is from third parties; - The only modification I will do is rescaling, I will not work with the colors - It doesn't matter what it looks like on my monitor, only the printing result matters. - The final product will be printed at a printing company, not by me. The material consists of PDF's containing both graphics and images (mostly in CMYK colorspace, though some could be in RGB), and photos taken by just some ordinary people with a digital camera that could be your or mine (RGB jpg's mostly). But, if I open a PDF containing one piece of the original material, and a PDF exported by scribus containing the aforementioned PDF, there quality is visibly reduced in the exported PDF; colors are pale, and dark areas are more prominently black. Particularly, skin color becomes really pale. I have tried exporting without and with color management (with several different profiles), and with and without converting to process colours when not using color management. I got the best (but still not very good) results without color management and by converting colors to process colors. I even tried with the Web/Screen color profile instead of Press, but neither that gave good results. Also, I'm suspecting that ghostscript rasterises PDF's as RGB bitmaps (even if they are originally CMYK), and then Scribus converts this back to CMYK (if press setting is selected in the export to PDF dialog). I hope this is not the case. Can anyone verify, if this is the case or not? Here's an example what happens to the colors, with color management disabled. (as it should in my case?). I have a PDF that needs to be embedded with a large area of almost the same shade of a blue; in the original PDF the %values for the blue at a certain point are roughly: 45 C 11 M 6 Y 0 K But, after importing the PDF into scribus, and exporting as PDF (with press setting in the color tab), and looking at the same area: 39 C 5 M 0 Y 7 K There is a HUGE difference in the overall amount of black and yellow channel used in the picture when compared to the original. It seems Scribus maximizes K in the cost of CMY (in this case, Y), and it really looks bad. I got this information at the printing company (I think we used Adobe Photoshop for comparison, tough I could be wrong about the program, it could have been some other Adobe tool - however I saw the effect of showing only the black channel in the original PDF and the PDF I had exported from Scribus). The same "conversion" is done for all RGB pictures. I want to achieve this: all graphics should remain as is - i.e. RGB pictures should remain as RGB pictures, and the numerical CMYK values should be left untouched. The printing company agrees (or actually recommended this). Is this possible with Scribus? Thanks for the help in advance! I'll be happy to answer any questions. -- -- Ville Aakko - ville.aakko at gmail.com
