19 Replies Latest reply: Aug 31, 2009 1:20 PM by jberg0007 RSS

    Line art problem outputting to pdf

    ChrisH94 Community Member

      I have a problem with exporting pages of a magazine going to print as pdf, relating to line art placed on the page as a bitmap tiff (typically at 1200 ppi). At present I have a workaround for an annoying problem that really needs clearing up ...

       

      I'm using CS4 InDesign and Acrobat (files prepared in Photoshop). So, high-res bitmap tiff containing line art sized (that is, just placed - no resizing in Indesign) and placed in Indesign, looks fine on the page. Output to pdf using 'export' and the resulting file, when viewed on screen, has a thin line down the right-hand edge of any and all bitmap files.

       

      To ensure no misunderstanding, the 'bitmap' reference is what Photoshop calls it - a bilevel file with black lines in it, which enables me easily to overlay other files such as a photo (because the file is black/transparent) and assign a colour or tint to the bitmap, or even a drop shadow etc. I've used this workflow for years, from Photoshop through Indesign, but the latter always gives me this line on the right edge, in the pdf. It did this in CS3 Indesign/Acrobat as well (but never in Pagemaker).

       

      My workaround is to lay a white-filled box over the edge of the file, thus masking it. But of course, that also limits me to where I can place the file - not easily on a graded tint background, not on a photo and so on. So I'd like to solve this.

       

      Any ideas? OS is Win XP Pro (all updates applied to this and the CS programs - I don't believe they make a difference to this problem, as it has existed through several iterations of both OS and CS).

       

      Anyone else seen this effect? Or is it just me? And has anyone a potential solution?

       

      Chris

        • 1. Re: Line art problem outputting to pdf
          rob day MVP

          In your PDF export preset do you have Compression>Monochrome Images set to Do Not Downsample, Compression to None, and Compress Text and Line Art unchecked?

           

          Also, if you are using transparency are you keeping the transparency in the exported PDF or flattening (PDF 1.3)?

          • 2. Re: Line art problem outputting to pdf
            Peter Spier ACP/MVPs

            I've seen this on screen in the PDF, but it seems to be a display artifact that disappears in different zoom levels and in print.

            • 3. Re: Line art problem outputting to pdf
              ChrisH94 Community Member

              Thanks for the input. I had it set to only downsample if some silly huge size, and yes, to compress text and line art. I have now prepared a new present, with the parameters you list, but there is no difference to the result.

               

              The pdf is indeed flattened to 1.3 (Acrobat 4). I've always liked producing the most basic file I can.

               

              I should add that the line at the edge of the file is very, very fine - but very very visible on screen (I've not wanted to risk it appearing on a printed page by leaving it to chance that it might not print).

              • 4. Re: Line art problem outputting to pdf
                ChrisH94 Community Member

                Yes, I agree - it disappears at different enlargements (it is very obvious at 100% though). I just haven't wished to risk putting it out to offset litho print = a bit embarrassing if it turns up on the printed page. But in any case, the pdf itself is used as a digital file and this looks less than professional with a thin line where it shouldn't be, so even if a display artifact, I cannot leave it there.

                • 5. Re: Line art problem outputting to pdf
                  Peter Spier ACP/MVPs

                  It happened on the last job I did, which is being printed now, without issue, on a Minolta BizHub. I'd be even less concerned about press output.

                  • 6. Re: Line art problem outputting to pdf
                    rob day MVP

                    Does it happen when there's no transparency on the page?

                     

                    If you are using transparency and flattening on export the line art is no longer line art so you would have to consider the Color and Grayscale Compression and Downsampling setting also. If you leave it at the default 300 ppi your line art is going to get resampled to 300 even if you use a high resolution transparency preset with line art set to 1200.

                    • 7. Re: Line art problem outputting to pdf
                      ChrisH94 Community Member

                      Thanks - that's encouraging

                      • 8. Re: Line art problem outputting to pdf
                        ChrisH94 Community Member

                        I can put nothing whatsoever on the page other than the one line art file, and it produces the line on the right edge.

                         

                        I do have downsampling enabled for greyscale and colour, though it's set to only do so for files above 1600 ppi - that is, just in case something silly creeps in it downsamples these files only. That's well above the ppi for the file in question, which is 1200, so it shouldn't be touched in any case. But, just to check, I produced a new preset with no downsampling and no compression. No difference to the output.

                         

                        I'm starting to suspect this is some sort of bug and insoluble ... Makes me (almost) want to go back to Pagemaker - no problems with that (I used the same settings in pdf production from the postscript file, when working there).

                         

                        It's encouraging that at least one other person doesn't see this appear in actual print, but it certainly prevents me having the freedom to produce some layouts, because the pdf also has to look good for digital versions of the magazine.

                        • 9. Re: Line art problem outputting to pdf
                          Peter Spier ACP/MVPs

                          My file used no transparency and was not flattened. It did use compression to text and line art. Curiously, it is not showing the artifacts now, either on my desktop which is in test mode this week and running Acrobat 8, nor on my laptop in Acrobat 9. The artifacts were evident before on the desktop in Acrobat 9.

                          • 10. Re: Line art problem outputting to pdf
                            ChrisH94 Community Member

                            Curious ... Seems to me that way back sometime, I noted that sometimes I *didn't'* get this line on the edge when viewed as a pdf - but I never found any reason for this. I couldn't track down any common factor - something missing from one page and present on all others, or whatever. And I failed to re-create the 'lack of problem'. I've lived with this for ages ... It's just so annoying that I need to avoid the on-screen display looking like a mistake, or else I would probably risk trying a file through to print to see if it really does appear.

                            • 11. Re: Line art problem outputting to pdf
                              rob day MVP

                              I'm using 8 and can't reproduce the problem.

                              • 12. Re: Line art problem outputting to pdf
                                ChrisH94 Community Member

                                I'm using 9, but it appeared in 8 before this ... I know it's been with me for many many months, since my switch to Indesign (which was quite late, only with CS3).

                                 

                                Bearing in mind that the line appears and disappears at certain magnifications, and that Peter commented that he had seen this happen as well but that it didn't turn up in print, *could* this be a screen artifact? That is, there is indeed something in the pdf that records as a line, but whether it appears on screen depends on the monitor resolution or type? Shows on LCD, not on the old sort? Shows on LCD set to 1280 but not on some other resolution?

                                 

                                I'm clutching straws here - but thanks guys for your time and ideas.

                                • 13. Re: Line art problem outputting to pdf
                                  Steve Werner ACP/MVPs

                                  The line artifacts in PDFs have been reported for many years. They most often happen when flattening is turned on—for example, creating a PDF/X-1a file.

                                   

                                  Usually, they will disappear if you turn OFF "Smooth Line Art" option in Acrobat's Page Display preferences.

                                   

                                  See this thread in the Design and Development > PDF Workflow forum:

                                   

                                  http://forums.adobe.com/thread/285775;jsessionid=EA3D347964C72E84E681F4D773A4D1AB.node0?ts tart=0

                                   

                                  As Peter as pointed out, they almost never appear in printed output.

                                  • 14. Re: Line art problem outputting to pdf
                                    rob day MVP

                                    but it certainly prevents me having the freedom to produce some layouts, because the pdf also has to look good for digital versions of the magazine.

                                     

                                    Does it show in Acrobat Reader?

                                    • 15. Re: Line art problem outputting to pdf
                                      ChrisH94 Community Member

                                      That's encouraging in that others have had this hassle (if you see what I mean!), and that they also confirm that it doesn't reach the printed page. I'm going to leave a line in my output (which goes to print tonight, one way or another), to see what happens.

                                       

                                      I tried turning off smoothing - made no difference to the edge line appearing; I can still see it (though I might convince myself that it isn't so noticeable).

                                      • 16. Re: Line art problem outputting to pdf
                                        ChrisH94 Community Member

                                        Actually, I don't know - I'll check but can't do so quickly, as I don't have Reader loaded on the machine I'm on at present. (I'm in the UK, working late as the files *must* upload tonight, so I won't be installing Reader at present or transferring to a different computer).

                                         

                                        Good idea though, something to check.

                                        • 17. Re: Line art problem outputting to pdf
                                          Peter Spier ACP/MVPs

                                          I think this is somewhat akin to seeing differences in weight on screen for lines in a graph. I often see some rendered more heavily than others, and some drop out entirely, and it seems to be entirely a function of screen size, resolution, and magnification, coupled with the smoothing options. These are things you cannot control on other users' systems, just as you cannot control their browser's display of your web page in any absolute way. For all I know it is different on Mac and Windows, too, in the same way that type renders a little differently.

                                           

                                          At this point I just shrug and say "fact of life."

                                          • 18. Re: Line art problem outputting to pdf
                                            ChrisH94 Community Member

                                            I think by reason of not knowing what else I can do, I'm heading to the same conclusion - put up with it! I'll certainly try sending a line to print and see if it appears, but for on-screen stuff, I think I have to stick with the safe workaround I use and accept the layout limitations. (Or resort to Pagemaker for the pages that I just cannot do otherwise.)

                                             

                                            Seems to me, if people have reported this for years, Adobe might have tried sorting it out. On screen or not, it still must be due to *something* in the file and/or Acrobat/Distiller to allow it to appear. If I create a white greyscale tiff with the same resolution etc, and place it on a page, there's no line down the edge on output - just a white page with a white (invisible) box. If I do this with an 'empty' bitmap file, a line appears ... Both files created in Adobe programs, so it's not me as a user ...

                                             

                                            Just me whinging! I'm really coming from the angle that if this is indeed a display problem, it can only be a display problem if there is something in the file for the display to react to (badly phrased that!).

                                             

                                            Thanks everyone for your support and ideas - I think that's me finished for now; I have files to upload and then sleep.

                                            • 19. Re: Line art problem outputting to pdf
                                              jberg0007

                                              Try this:

                                              Switch off Object level compression in Distiller and then the line will disappear.

                                               

                                              Open Distiller, go to Adobe PDF settings and then select the Edit Adobe PDF Settings. There is a dropdown box for Object level compression, which is usually set to maximum.

                                               

                                              Set it to off.

                                              ___

                                               

                                              This worked for me on PC.

                                              I was getting the problem when I used transparent effects (like drop shadows) on any object including imported line art. Happened in InDesign and Illustrator when making a PDF. Was also getting boxes around my imported bitmaps with transparent background. They were only onscreen and would never print. But after making these setting changes you need to export to PDF (as opposed to just printing to PDF). The file size will be larger, but the lines dissapear.

                                               

                                              Hope that helps your issue.