Does exporting to pdf decrease the quality?

[Komodo]

I’m using GIMP 2.10.4 and I was wondering if I lose image quality when I export as pdf?

Will I keep my 300.000 pixels/in for example?

[rich2005]

(08-30-2018, 02:12 PM)Komodo Wrote: I’m using GIMP 2.10.4 and I was wondering if I lose image quality when I export as pdf?

Will I keep my 300.000 pixels/in for example?

The short answer: yes, you keep the quality

A bit longer:

If you have used the template from the printer and the print resolution is 300 ppi then Gimp will make an equivalent PDF.

If you use Gimp to check the PDF: Gimp will always use a default value of 100 ppi. Change that value to 300 when you import the PDF as a check.



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Nothing to do with this topic but thinking about your earlier posts about transparency and flattening an image.

You can have transparency in a PDF but guessing the printing co. does not want that.

By all means check what the image looks like with a cream paper, but export to pdf with a white background. a sort of comparison: https://i.imgur.com/HJEqqQS.jpg

I mentioned Scribus before, a DTP application and this is why transparency is not a good idea. https://i.imgur.com/jPqAHxL.jpg

but Scribus is the best way to get a PDF for submitting to the printing co. It can add those crop marks, all the things printers love. https://i.imgur.com/Vngrl0q.jpg

Is there a  difference between Scribus PDF and a Gimp PDF, not much the Gimp a little larger file size and the Scribus has those crop margins added. https://i.imgur.com/3xEgriZ.jpg

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If all that is a bit too much for you, Make your image with the size you stated earlier, 
Size in pixels: 3915 x 2775 pixels, check the print resolution is 300 ppi, export to a PDF.

[Komodo]

Thank you very much rich2005 for the detailed explanation. If I understand, as far as the transparence is concerned you are saying not to use it but to flatten as CreateSpace says.

I tested the image on a color photocopy machine at work and both the flattened and transparency images printed the same on yellow paper. As you said before, it does not print the white area.

I also printed the same images after a pdf conversion with the same results.

BTW, CreateSpace is not available for printing books of any kind as of this week. They are sending all their costumers to KDP. Apparently they both have the same printing prerequisites.

Thanks again