7 Replies Latest reply: Aug 3, 2012 12:08 PM by habanero_jefe RSS

    Press pdf's photos look low res

    habanero_jefe

      Hey,

       

      I wrote a press pdf of an Indesign file that incorporated photography. It looked great as usual. But I imported the same content for a resize and wrote a new press pdf and the photo part of the pdf looks very low resolution. I reimported the photos and tried again. But now I'm at a loss. Anyone help please?

        • 1. Re: Press pdf's photos look low res
          Steve Werner ACP/MVPs

          I'm not following your workflow. Please describe more accurately.

           

          "But I imported the same content for a resize..." What was imported into which application?

           

          When you say "wrote a press pdf" what exactly did you do? Did you use File > Export > Adobe PDF from InDesign? Did you create a PostScript file and use Distiller? Which PDF settings did you use?

           

          How are you determining that the PDF "looks very low resolution"? Have you examined it with Acrobat Pro's Output Preview > Object Inspector? There you could measure the actual resolution (ppi) of the images.

          • 2. Re: Press pdf's photos look low res
            habanero_jefe Community Member

            After successfully writing(exporting) a press pdf of an ad created in Indesign. I copied the Indesign's file content to another Indesign file with a slightly different size. I wrote another press pdf of the new Indesign file and the photography (on the new pdf) looks horribly low res. But nothing about the photos changed except they're slightly (5%) smaller. No new settings in either program (Acrobat or Indesign) So I have one press pdf that looks brilliant and the other like a zerox copy. I can't figure out why. Never happened before. Type looks great, border rules look great. Everything but the photography.

             

            I'll explore using the object inspector as you suggested. But I doubt it'll tell me why the photos look great in one pdf and not the other. When nothing should have changed.

             

            Thanks for getting back to me.

            • 3. Re: Press pdf's photos look low res
              Daniel Flavin Community Member

              In the second InDesign file - do the links show as Up to Date in the Links Panel and export without warnings?

               

              Verify that the first file has the images linked and not embedded, as well...

              • 4. Re: Press pdf's photos look low res
                habanero_jefe Community Member

                Thanks for your response Mr Flavin. I think I may have figured it out. The photo images were Bitmap 600dpi (but reduced to fit the smaller layout) I actually reduced resolution to 400 and the pdf images look less like bad zerox copies - less clogged up.

                 

                I think that was the problem. They still don't look as good as the photo images on the larger press pdf. Make any sense?

                • 5. Re: Press pdf's photos look low res
                  Bill@VT MVP

                  As you are finding, a lot depends on how you are creating the PDF. I assume it is with the export option in ID, not Acrobat. When you change size on a bitmap, a resolution change in PDF can cause a lot of problems because of the way the original bitmap may be down sampled and put into the new resolution. Always a danger when playing with scaling of bitmaps (why vector graphics are preferred when appropriate -- of course, not for photos and such). I suspect it all goes back to the sampling that is being forced. In the future, you might want to scale the graphic in an appropriate program (maybe PhotoShop) to get the desired size and resolution and use that in the ID layout, not just a copy, paste, scale. The graphics programs are more geared to properly scaling a bitmap.

                  • 6. Re: Press pdf's photos look low res
                    Daniel Flavin Community Member

                    IMO, a bitmap image would be appropriate for a black & white/monotone graphic, but a tonal image requires grayscale space.

                    • 7. Re: Press pdf's photos look low res
                      habanero_jefe Community Member

                      Thanks. The copy,paste,scale method in ID just doesn't work. I will do the sizing in PS and adjust bimap accordingly. They're beautiful bitmaps. I'm glad to know what to do with them next time.