16 Replies Latest reply on Jan 27, 2010 1:28 PM by bobzilla63

    converting PDF to grayscale

    Level 1
      I am using Adobe CS 3, Acrobat 8 Professional, on Mac OS 10.4.11

      I am trying to convert a full color PDF document to grayscale. I tried to click Advanced > Print Production > Convert Colors and then Grayscale, but it is not working.

      I tried clicking Print and then choosing a PDF option, but it is taking unreasonably long and not finishing.

      So how can I convert it to grayscale?
        • 1. Re: converting PDF to grayscale
          You might want to try 'Quite a box of tricks' (www.quite.com). Apart from converting color PDF's to Grayscale very fast, this plugin can rotate, resize or downscale your PDF-file.
          • 2. Re: converting PDF to grayscale
            Level 1
            Are you selecting the various colour space at the top and telling each
            of those to convert?

            You need to fine-tune slightly - it does work

            • 3. Re: converting PDF to grayscale
              KC29 Level 3
              Another option is...

              On the PDF do a Save As > Postscript

              Then go to Settings > Output > Colour > Composite Grey

              Then run that through Distiller.

              It's worked for me
              • 4. Re: converting PDF to grayscale
                Level 1
                But why perform those steps if the conversion inside Acrobat works?
                We're dealing with PDF objects so there's no reason why it shouldn't
                work (make sure you're fully patched though) ....

                • 5. Re: converting PDF to grayscale
                  Level 1
                  The Acrobat conversion will indeed make a grayscale (one color) file. These settings will give you a starting point: Advanced> print production> convert colors> document colors- device cmyk: convert> action: convert> profile: gray gamma 1.6> blending profile> device gray> conversion options> don't embed profile.
                  To check your grayscale PDF, use the output preview (print production> output preview) and toggle the black sep. on and off. Another option is to use Pitstop.
                  • 6. Re: converting PDF to grayscale
                    I am trying to do the same thing, but in Acrobat Pro 7.

                    The problem is that the document has the text set in rich black instead of only black. When I convert it to gray, it comes out 84% - 96% black, depending on the profile and option that I use.

                    In the Profile, there is only gamma 2.2 and gamma 1.8. How can I add gamma 1.6, or 1.0? I think if I do that the conversion will be the way I want it.
                    • 7. Re: converting PDF to grayscale
                      Level 1
                      Make sure you DON'T EMBED the profile and ensure you PRESERVE the black
                      objects ...

                      • 8. Re: converting PDF to grayscale
                        Level 1
                        I tried this in acrobat 7 and some of the black builds still don't convert. It's probably just another problem that was addressed with the new CS3, hence the reason there is gamma 1.6 in acrobat 8 and not 7. I'm trying to convert a 33 page pdf booklet that a lady sent to me. Unfortunately adobe made this option available but not fully functional, which sucks because explaining to her what the problem with her pdf is much harder and more time consuming than converting it to grayscale myself.
                        • 9. Re: converting PDF to grayscale
                          I have this problem too - some objects doesn't convert. I used Acrobat 7 some old version - it worked fine, but updated it to 7.1 - now it leaves some objects CMYK. When I try to edit those objects in Photoshop - it gives me a warning: "Could not complete your request because a colour was specified using an unsupported colour space". With the old Acrobat all I had to do is to take this object to another page (I have an "empty" file specially for this task), convert it there to SWOPv2 for example - and I was able to work with it from there. Now it doesn't convert anymore.
                          I am afraid it's something with color settings - that's scary because I don't understand much in it, it's so complicated - because when I took one of those files on another machine and tried to open this "problem" object - it opened in Photoshop without problems (CS3) and showed that it is... Grayscale!
                          Please, help, any ideas? I need to fix up to 20 files every day...
                          Thank you in advance
                          • 10. Re: converting PDF to grayscale
                            levonk Level 1
                            I used PitStop to change the colors and add more black to them, then I used the convert colors option in Acrobat, and it worked.

                            Vera, you may also need to get PitStop for your job. It has many options that Acrobat does not have, and is faster.
                            • 11. Re: converting PDF to grayscale
                              Level 1
                              With pdfToolbox from callas (check out the pdfColorConvert feature) it is a one click operation that works each time (and neither requires the use of arcane gamma value profiles nor any configuration). Black will and up on black plate only, and 100% (or more) black will come out as 100% black. Demo available at www.callassoftware.com. Apologies for the shameless plug.

                              Olaf Drümmer
                              callas software
                              • 12. Re: converting PDF to grayscale
                                Level 1
                                I think sometimes it's shameful not to plug ... especially if you think
                                the products fits the bill - it's all about solutions.

                                • 13. Re: converting PDF to grayscale
                                  Level 1
                                  Olaf's plugin is by far the best solution, especially if you're converting on a regular basis.
                                  • 14. Re: converting PDF to grayscale
                                    I had some trouble with this same issue of converting a color pdf to grayscale. I realized that in my particular pdf, just using the Tools/Print Production/Convert Colors function was not enough. Somehow there were extra spot colors inadvertently added to the file. Here are the steps to follow to make sure this works correctly if you are wanting to convert the entire pdf file to a grayscale image:

                                    (I am using Acrobat 7.0.9 on a Mac OS X, 10.4.11 system)

                                    1.) In your pdf file go to Tools/Print Production/Ink Manager click on the bottom left corner box that says (Convert all spots to process). Click okay.


                                    2.) Go back to Tools/Print Production/Convert Colors. Click on (Device Gray: Convert) Action: Convert. Profile: Select your profile of choosing....for me it was 10% Dot Gain way at the bottom). Convert Pages: All. Conversion Options: Don't Embed Profile. Check box that says, Preserve Black Objects. Click okay.

                                    This should resolve any problems with those extra colors that will not convert to grayscale since they are assigned as spot colors.

                                    Hope this helps. Let me know if this works for anyone. just tried it once.

                                    Good luck!
                                    • 15. Re: converting PDF to grayscale
                                      Level 1
                                      Acrobat 7 was the first incarnation of the convert colors option - I
                                      would recommend using Acrobat 8 which was better but Acrobat 9 which is
                                      superb ...

                                      • 16. Re: converting PDF to grayscale
                                        bobzilla63 Level 1

                                        How can I do the conversion on a batch of PDFs?


                                        It seems Acrobat's file formats for saving or exporting are different whendoing one a t a time than they are if you wanted to batch them.