8 Replies Latest reply on Jun 28, 2011 6:01 AM by Eugene Tyson

    Different colours in PDF

    Nick van der Aa

      ww.jpg

       

      I'm trying to make a simple little brochure in Indesign (my first time) but when i save this document to PDF the colour near the palm tree is a little darker than the rest of the black. I took the black colour from the palm picture (it's surounded with black) with the eye dropper tool, so it has to be exactly the same colour right?

       

      This is a JPEG and the black colours match, even on the highest resolution. What do I do wrong when saving in PDF?

        • 1. Re: Different colours in PDF
          John Hawkinson Level 5

          Are we supposed to be able to see the problem in your supplied image?

           

          JPEGs can easily represent solid colors poorly -- there may in fact not be a uniform field. Turn on high-resoluton previews and zoom all the way in, at the pixel level. (You might want to do this in Photoshop). What's the value of the color you selected?

           

          In any case, it would be easier to help you with an image of the problem...

          • 2. Re: Different colours in PDF
            Peter Spier Most Valuable Participant (Moderator)

            Nick van der Aa wrote:

             

            I took the black colour from the palm picture (it's surounded with black) with the eye dropper tool, so it has to be exactly the same colour right?

             

            This is a JPEG and the black colours match

            Any photograph witha black background is going to have shades of black, not a single color, unless you adjust it heavily to clip the darker shades. You matched one pixel, if you used the eyedropper in ID (and maybe only one pixel from the preview, not the actual image), or if you used the eydropper in photoshot to get the values you sampled only one pixel, or an average over a small area. The odds of getting a match to the whole background are slip to none.

             

            Instead of trying to match the background, remove it.

            • 3. Re: Different colours in PDF
              Nick van der Aa Level 1

              The picture you see is a JPEG, so you don't see the difference in the colour.

               

              I tried to make a screenpic of the PDF file, but it can only be saved as a TIFF file (on Mac), so i can't post it here (or there has to be another way)

               

              The problem is: everything looks fine when working in Indesign. Only when saving to PDF i see that the colours aren't correct.

               

              I guess i could fix it by removing the background from the palmpicture (can i do that in Indesign?), but than i don't learn what the problem is and it probably will happen again.

              • 4. Re: Different colours in PDF
                Nick van der Aa Level 1

                Sorry, didn't read the last post good enough. My bad!

                 

                 

                That's leaves two questions for me:

                 

                - How come Indesign doesn't show me that the two black colours don't match?

                 

                - Can I erase the background with Indesign? (Take away the black that surrounds the palmtree image)

                • 5. Re: Different colours in PDF
                  Eugene Tyson Adobe Community Professional & MVP

                  InDesign has preferences to how Black is output or viewed on RGB devices.

                   

                  In Preferences>Appearance

                   

                  Display black on screen as Display Accuartely or Display as Rich Black.

                   

                  I have mine set to Display Accurately.

                   

                   

                  This only affects RGB devices and nothing to do with PDF for professional printing.

                  • 6. Re: Different colours in PDF
                    Eugene Tyson Adobe Community Professional & MVP

                    In regards to removing the black - I have no idea how you setup your file.

                    1 person found this helpful
                    • 7. Re: Different colours in PDF
                      Nick van der Aa Level 1

                      Thanks, that's it!

                       

                      Little off topic, but any idea how come that my exports are more blurry than the originals in Indesign? (Even on high qualty print)

                      • 8. Re: Different colours in PDF
                        Eugene Tyson Adobe Community Professional & MVP

                        What resolution are your images? Check the Window>info panel and select an image that is causing a problem.

                         

                        There are two readings Actual PPI and Effective PPI

                         

                        You will have to give us the Effective PPI.

                         

                         

                        Also, if you print directly from InDesign under Graphics there is an option to Send All, Optimised Subsampling, Proxy and NONE

                         

                        Send All sends all the graphic data, Optimised Subsampling I think reduces the quality, Proxy sends just the thumbnail info and NONE won't print any images.

                         

                         

                        And if you make a PDF the images can be reduced in quality in the Compression by choosing Downsample to (whatever number) for images Above a certain PPI. So your images can be reduced in quality when making the PDF. You'll have to make sure you have the correct PPI set.

                         

                        As with the Effective PPI if your image is 900 as listed under this - then if you make the pdf and have it set to Downsampe to 72 ppi for images above 120 ppi or something, then any image above 120 will be resampled to just 72.

                         

                        If this is going to print you can choose Downsample to 300 for images above 450 ppi - this means that any image that is effectively above the 450ppi will be reduced to 300 ppi which would be adequate for printing at a professional printers.