13 Replies Latest reply on Oct 3, 2011 5:10 PM by Ryadia™

    InDesign and (Postscript 3) output resolution issues

    Ryadia™ Level 1

      Hello all

      This issue was previously posted to print design where I got a reply to take it here. I also got a mostly useful reply too but it did not resolve the issue.

       

      I build magazines, calendars and other photographicly illustrated documents. My problem is in not being able to get the same print quality from my Xerox C2255 Postscript printer as I can get using Photoshop. Specifically it concerns the quality of photographs. If I print using Photoshop CS5 I can build a document at 1200 dpi and set the output resolution to 1200 dpi in the printer dialogue. The results are very close to medium quality offset press work. Quite good enough for my calendars.

       

      When I place the same 1200 dpi image into inDesign, the results look more like 300 dpi than 1200. My specific question then is can someone please tell me how I set the output resolution of inDesign either during creation of a PDF or directly to the Postscript 3 printer. I can set the printer to show it is set at 1200 dpi but the results are not consistant with Photoshop results using the same printer settings. This problem is common with both ID CS4 and CS5 and Acrobat 9 Pro on two different Very frustrating because a popular Canadian page layout program can produce the results an old PPD file from 2003. ID doesn't like that one, I might add.

       

      Two machines, same problem

      one i5 the other i7

      ID CS4 and CS5

      Windows XP Pro7 and Win7 Pro

      4 gig RAM (XP Pro)

      16 Gig RAM (Win7)

       

      Xerox C2255 LED printer

      with 1536 MB (full) RAM and hard drive.

       

      Help in any form apreciated.

       

      Doug

        • 1. Re: InDesign and (Postscript 3) output resolution issues
          Peter Spier Most Valuable Participant (Moderator)

          A couple of questions...

           

          Are you scaling the photos in ID? If so, how much?

           

          Have you reset the default from Optimized Subsampling to All for the Send Data field in the graphics panel of the Print dialog?

           

          Now for the biggie. Why 1200 ppi? An effective resolution (the resolution of the image at the scaled size, which you can read in the info panel) is more than adequate even for most press work. Too much resolution is actually just going to result in extended processing times and the extra data being thrown away, and it may even result in poorer image quailty than using the correct lower resolution to start.

          1 person found this helpful
          • 2. Re: InDesign and (Postscript 3) output resolution issues
            Ryadia™ Level 1

            No scaling. Fortunately with a calendar or a magazine areas used for graphics are set when I make the template. Then you can work all your photos in 'shop and just place them in ID.

             

            I just set the subsampling and ran a print. Excellent! Thank you very much for this simple but correct answer.

                

            As to the resolution... Although LED printers are marketed as "lasers" they don't actually use a laser beam and spinning mirror for image transfer. They work more like a commercial photo printing machine that prints real photographs than a laser printer and they do benefit from resolution increasing. At 300 dpi pale areas of sky show typical laser degradation - streaks and screen marks. At 600 dpi the image starts to look better but at 1200 dpi it looks like a photograph.

             

            The trade off is RAM and time. Fortunately these Xerox machines have a fast CPU and can accept 1536 Mb or RAM. Then when you print at 1200 dpi, the results are as good as or better than many inkjet photo printers. I happy now, thanks to your understanding of inDesign and how it outputs. The sample I just ran was a 600 dpi image. Then I re-edited the original to 1200 dpi and printed it again.

             

            Now the results are what I expected. Am I right in my opinion that inDesign will send images to a devise at a resampled resolution of 300 dpi unless you change that print setting? And when you specify "all" ID will send the full image? I've been using pagemaker since 1995. When I changed to indesign in 2005, I also started printing and platemaking myself. When I bought digital printing gear (LED printers) in '08 it was only to proof magazines. The Minolta I had before this Xerox printed incredibly good quality. That was when I decided to print my own low volume items and the resolution issue surfaced.

             

            I had previously overcome it by using a Canadian layout suite. Now I'm pretty sure I'll get the usage from inDesign with this Xerox I expected to in the first place. Again... Thank you .

            Doug.

            • 3. Re: InDesign and (Postscript 3) output resolution issues
              Peter Spier Most Valuable Participant (Moderator)

              ID reads the printer resolution, or default screen, or something -- I don't really know how this works, probably from a PPD file for Postscript printers -- and resamples images to the "optimum" value for the device. I suspect that optimum is more tuned to processing time than to anything else, and it seems to be pretty uninversally true that sending all data gives a better print, though it probably takes longer. I would bet for the Xerox the subsample is as low as 200 ppi, maybe less.

              • 4. Re: InDesign and (Postscript 3) output resolution issues
                John Hawkinson Level 5

                Peter wrote:

                ID reads the printer resolution, or default screen, or something -- I don't really know how this works, probably from a PPD file for Postscript printers

                It turns out InDesign asks the AdobeAGM library what the printer's resolution is, and under Windows, AdobeAGM calls the Win32 API GetDeviceCaps and uses the best resolution returned. On the Mac I don't know what it does. Ultimately this data appears to come from the PPD file. If the OS doesn't return anything, InDesign chooses 1200ppi. (At least, that's what Adobe Support told me that InDesign Engineering told them in regards to my open bug #2902023 about Xerox laser printers printing horribly low quality for 1bpp images.)

                 

                and resamples images to the "optimum" value for the device. I suspect that optimum is more tuned to processing time than to anything else, and it seems to be pretty uninversally true that sending all data gives a better print, though it probably takes longer.

                Gosh, that's not my understanding at all. My understanding is "optimum" means "something the printer would never print anyway." i.e. It resamples higher resolution data to the printer's specified maximum resolution if the image is higher than that. The idea is to save transmission time (and perhaps printer processing time), but not at the expense of quality.

                • 5. Re: InDesign and (Postscript 3) output resolution issues
                  Peter Spier Most Valuable Participant (Moderator)

                  John,

                   

                  I'm not sure I'm following the second part of your post, and so I don't know if we are disagreeing about anything.  My response was based on my (possibly faulty) recollection of a post Dov made sometime in the past) about optimized subsampling, and empirical results reported by MANY users regarding the immediate improvement in quality when resetting to ALL.

                   

                  Optimized Subsampling is maybe not SUPPOSED to reduce image quality in the print, but it definitely does for a lot of printers. I have no idea what method is used to downsample, but it defintiely leads to poorer results than you would get by resizing first in Photoshop to the correct dimensions and resolution for the device, and usually poorere results than sending all data for an image that you have not resampled externally.

                  • 6. Re: InDesign and (Postscript 3) output resolution issues
                    Ryadia™ Level 1

                    Well John, now that I've successfully followed Peter's advice and got ID to output at true 1200 dpi, I can tell you this much... Peter is the only person who answered my posts here or in print design forum that actually knew what I had to do to get the same quality printing from InDesign as I did from Photoshop.

                     

                    Peter is right on the ball in describing how ID handles printing to a Postscript printer. When "Optimum" image resampling takes place it is based on the lowest common denominator. I presume this is so ID will at least print a document which some might argue is preferable to having the page not print at all.

                     

                    The somewhat cryptic Adobe instructions for setting up print output results in ID defaulting to "Optmium sub-sampling" when printing. Read that as a compromise using the lowest common denominator (300 dpi) or in the case of this description "under sampling" the image rather than over sampling it.

                     

                    So John, When you decide what Optimum means in the future, it might be wise to read the word in conjunction with what it relates to. In the case of this discussion it is "Sub-Sampling". Where "Sub" means under.

                     

                    Doug.

                    • 7. Re: InDesign and (Postscript 3) output resolution issues
                      John Hawkinson Level 5

                      Peter:

                      I'm not sure I'm following the second part of your post, and so I don't know if we are disagreeing about anything.

                      Let's fight like this:

                        A!

                        NOT B!

                        A!

                        NOT B!

                        ...

                        [Eventually someone points out that A=NOT B]

                       

                      I was attempting to describe what I believe Optimized Subsampling is supposed to do, i.e. the meaning of optimum in this context. Because it sounded like you were expressing that perhaps what was being optimized was intended to be visibly different, and I believe that's incorrect.

                       

                      Optimized Subsampling is maybe not SUPPOSED to reduce image quality in the print, but it definitely does for a lot of printers.

                      Sure, no question!

                       

                      Doug:

                      Peter is right on the ball in describing how ID handles printing to a Postscript printer. When "Optimum" image resampling takes place it is based on the lowest common denominator.

                      Err...That is inaccurate. Optimized subsampling is not based on the lowest common resolution (denominator?). In fact, it is supposed to be based on the HIGHEST common resolution. Unfortunately we know that empirically, it fails to work right in some situations. This behavior is a bug. (As I said, at least one aspect of it is covered by bug #2902023.)

                       

                      So, when everything is working right, OSS should result in no visible difference, just faster printing because data is thrown away on the computer rather than on the printer. For many printer configurations this is a noticable speed difference on image-heavy layouts.

                       

                      If the problem stems from your PPD file, you may also be able to improve the situation by adjusting

                      the resolution specification in your PPD file.

                      • 8. Re: InDesign and (Postscript 3) output resolution issues
                        BobLevine MVP & Adobe Community Professional

                        Optimized subsampling is a relic of days gone by when it was included to show software reviewers how fast the application could print.

                         

                        You guys can argue semantics all you want but the fact is the results are almost always lousy and this setting has almost no useful purpose in today's workflow. Why it's there as the default in this day and age is beyond me.

                         

                        Bob

                        • 9. Re: InDesign and (Postscript 3) output resolution issues
                          John Hawkinson Level 5

                          Bob, I'm going to have to disagree on all counts:

                           

                          Optimized subsampling is a relic of days gone by when it was included to show software reviewers how fast the application could print.

                          We have a production environment where we print a lot of proofs on a deadline. As we are preparing to go to press, we review page proofs and catch a lot of last minute errors on paper, make edits, and reprint pages. Sometimes the print-read-revise-reprint cycle is as short as 10 or 15 seconds (usually it is several minutes though). We do not like sitting and waiting for the printer. Especially at 2am when everyone wants to go home.

                           

                          Generally we're printing tabloid pages from a 2x4 core 2.4 GHz Mac Pro via Gigabit Ethernet to a Xerox Phaser 7500. This is not ancient hardware. I suppose it's not this year's hardware either, but it is not slow and not behind the curve.

                          You guys can argue semantics all you want but the fact is the results are almost always lousy and this setting has almost no useful purpose in today's workflow

                          In our experience, once the PPD file is adjusted to produce good output for the Xerox, the results are not lousy. And they were not lousy (ever) with the HP it replaced.

                           

                          But the times for Send All Data were definitely lousy. For a graphics-heavy layout, we saw printing times go up from seconds to minutes (when we first got the Xerox before a workaround). That was murder on our workflow.

                           

                           

                          Why it's there as the default in this day and age is beyond me.

                          This one is trivial to answer! It's turned on because Adobe believes that it does no harm and confers a benefit in many cases. I suspect that they are unaware of the scope of the problems with it.

                           

                          (I'm somewhat unaware too. No hard data, just anecdotal mentions.)

                           

                          I agree that if it's an unreliable feature, then it's not doing anyone any good. Though I think the right solution is to fix it, not to turn it off, but I suppose it depends on how hard it is to fix.

                          • 10. Re: InDesign and (Postscript 3) output resolution issues
                            Gernot Hoffmann Level 3

                            "Sometimes the print-read-revise-reprint cycle is as short as 10 or 15 seconds"

                             

                            That's indeed an application for Optimized Subsampling - fast and dirty.

                             

                            Bob #8 is right ("almost always lousy...") and the InDesign help text is wrong:

                             

                            "Optimized Subsampling  Sends just enough image data to print the graphic at the

                            best possible resolution for the output device. (A high-resolution printer will use

                            more data than a low-resolution desktop model.) Select this option when you’re

                            working with high‑resolution images but printing proofs to a desktop printer."

                             

                            This mode does not respect the best possible resolution for high end PostScript

                            printers (toner printers, laser or LED). Concerning images, it's just a preview.

                             

                            That had been discussed already 10 years ago (PageMaker), may be it's now

                            different. I have to admit that I didn't check it actually.

                             

                            Best regards --Gernot Hoffmann

                            • 11. Re: InDesign and (Postscript 3) output resolution issues
                              John Hawkinson Level 5

                              This mode does not respect the best possible resolution for high end PostScript

                              printers (toner printers, laser or LED). Concerning images, it's just a preview.

                               

                              I do not agree.

                               

                              When it functions as designed, it does indeed respect the best possible resolution.

                              It functions as designed for me on HP printers, and on Xerox printers when their PPD files are editted to include resolution.

                               

                              You might have other data points, of course.

                               

                              It certainly makes sense for the documentation to document what the functionality is supposed to do -- other things are bugs.

                               

                              Ironically it's possible they are operating system bugs and not InDesign bugs (see my info about my bug above), but that sadly makes them harder to fix, not easier, it would seem.

                              • 13. Re: InDesign and (Postscript 3) output resolution issues
                                Ryadia™ Level 1

                                Gernot...

                                Everything discussed in that forum has been covered here except for the matter of printing speed when sending all the data instead of sub-sampling. Using modified PPD files that have the screen frequency messed with is a reciept for disaster. Why? Because optimium results with a laser or LED printer are achieved without using a traditional screen but by using digital noise (Frequency Modulation) in place of it.

                                 

                                Add to that the interchange of obsolete information being inserted into current technology discussions and it's easy to see why there are 100 or so unanswered question floating around various groups and forums asking the same question but no one having given a clear answer ...apart from Peter and even his answer does not fully address the issue. I'd love to know who coined the phrase "keep it simple stupid" because this will indeed result in getting near photographic quality, 1200 DPI output from inDesign when printing using a LED Xerox C2255.