Does exporting to pdf decrease the quality?

[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.