14 Replies Latest reply on Aug 4, 2016 2:13 PM by rob day

    Indesign CS6 Not picking up grayscale images in preflight check?

    RobFarmer

      I have a strange problem. I have set up a preflight profile to only accept CMYK images in the document. So it's checking for RGB, SPOT, GRAYSCALE etc.

       

      It's throwing up errors for spot, rgb but not for grayscale images??

       

      Any ideas why when i've ticked the do not allow grayscale box?

        • 1. Re: Indesign CS6 Not picking up grayscale images in preflight check?
          Test Screen Name Most Valuable Participant

          Don't know exactly how the profile works but if I were making a CMYK preflight I would always accept greyscale because it's just pure K.

          • 2. Re: Indesign CS6 Not picking up grayscale images in preflight check?
            RobFarmer Level 1

            It gets weirder. The original image was placed as

            Colourspace: grayscale

            Profile: 20% dot gain

            Colour within indesign set as black.

             

            I converted the image to RGB ... tried the image again. Indesign picks it up as RGB and errors it. Then converted the image to CMYK. Preflight passes it. Then Back to greyscale with 20% dotgain profile and colour set as black.

             

            And it flags it then as an error?! Grayscale image detected. Which is what it should do.

             

            So if i place the original Grayscale image into the document with the one which has been converted a few times and back to grayscale it's displaying an error for the converted one which is grayscale but ignoring the other image and passes it?!

            • 3. Re: Indesign CS6 Not picking up grayscale images in preflight check?
              RobFarmer Level 1

              The only difference i can see from the original file and to the one i've converted is the creator id

               

              The original placed image was saved from photoshop on windows.

               

              The other one which i've converted to multiple colour spaced and back to grayscale now has a creator id of photoshop on mac.

               

              God knows... Unless it's another bug...

              • 4. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                RobFarmer Level 1

                ah i've fixed it... The indesign template had 10% support black for the picture boxes where the images were placed. Because it's a support colour of 10% of cmyk the grayscale image placed into in it is no longer a grayscale image. Being the background colour is CMYK. Also the image is darker.

                 

                I would throttle the designer that set the template pages up if i knew who it was ! lol

                 

                I don't know about CC but the preflight should alert for grayscale images regardless if it has a background colour in the picture box :-/

                • 5. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                  rob day Adobe Community Professional & MVP

                  I don't know about CC but the preflight should alert for grayscale images regardless if it has a background colour in the picture box :-/

                  The handling of grayscales hasn't changed with CC. Grayscales with no transparency can have their foreground and background colorized. When you change either the image object is no longer a grayscale—if you export to PDF/X-4 without any color conversions you can check the object with AcrobatPro's Object inspector and see the change in color space:

                   

                  Here's the same grayscale with CMYK color applied (top), which exports as Indexed DeviceN and default [Black] bottom, which exports as DeviceGray

                   

                  Screen Shot 2016-08-04 at 12.53.03 PM.png

                   

                   

                  Screen Shot 2016-08-04 at 12.53.15 PM.png

                  • 6. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                    RobFarmer Level 1

                    Yep I worked all this out by trial and error. I'm having to rely on indesign preflight. it was only flagged up with the printers internal preflight which is probably going through a rip of some description with preflight.

                     

                    i understand the image is no longer grayscale if it has a colour background. In this case 2c2m2y4k .

                     

                    But if you select the preflight to alert for greyscale you expect it to flag up grayscale images . Hmmmmmmm

                    • 7. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                      rob day Adobe Community Professional & MVP

                      i understand the image is no longer grayscale if it has a colour background

                      Yes and that's why InDesign's preflight doesn't flag it.

                       

                      If preflight finds a grayscale what do you do, make some kind of conversion? Why does your printer need to flag grayscales? By default InDesign outputs them unchanged to the black plate, which seems desirable.

                      • 8. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                        RobFarmer Level 1

                        So why include the option to preflighting for grayscale images if it doesn't flag it up. Regardless if the background box has a colour attached to it. The image is still grayscale. Q.E.D.

                         

                        It it seems like a fundamental flaw to me.

                         

                        Regarding why they cannot be grey scale. The template pages have placement boxes designed with a colour to help the designer know where to multiple place the sourge images that are all placed at the same time. These images could be rgb / cmyk / greyscale. Which will have to be converted unless the cmyk files pass with the correct profile.

                        • 9. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                          rob day Adobe Community Professional & MVP

                          Regardless if the background box has a colour attached to it. The image is still grayscale. Q.E.D.

                          But it's not. If the image is a flattened grayscale the holding frame's color mixes with the gray pixels. So here the frame is 100% cyan so what was 50%gray is now 50|0|0|50 CMYK. AcrobatPro would not see this image as a grayscale:

                           

                          print.png

                           

                          These images could be rgb / cmyk / greyscale. Which will have to be converted

                           

                          What would you convert the grayscales to? Another gray space? A conversion to CMYK would produce 4-color blacks and grays and unless the profile is perfect for the press you'll probably get a color cast.

                          • 10. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                            rob day Adobe Community Professional & MVP

                            If you do want to convert grayscale to 4-color you could get a list via scripting—the scripting API will return the image mode whether color has been applied or not. If you are using OSX this Applescript would return a list of pages:

                             

                            tell application "Adobe InDesign CC 2014"

                                set ag to all graphics of active document

                                set lst to {}

                                repeat with x in ag

                                    if space of x is "Grayscale" then

                                        copy (name of parent page of x) & "," to end of lst

                                    end if

                                end repeat

                                display dialog "Grayscale images on pages: " & lst as string

                            end tell

                            • 11. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                              RobFarmer Level 1

                              I'm talking about the preflight within indesign. Once it gets to acrobat it's academic.

                               

                              Indesign is aware of the file format colour space so it should flag it regardless if its contained within a box with a background colour.

                               

                              How I see it the preflight check for grayscale only half works. If it's on paper then it works. If it's on a background colour it doesn't. Regardless if the background colour effects the colour values of the grayscale image. It's still a grayscale image. And should be flagged up in the preflight panel.

                              • 12. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                                RobFarmer Level 1

                                Thanks for the advice. I may use this script in the future but still doesn't fix the main issue with the preflight. :-/ Least I know what to look out for now. It's probably easier just to display the colour space in the links panel and manually preflight it .

                                • 13. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                                  rob day Adobe Community Professional & MVP

                                  Indesign is aware of the file format colour space so it should flag it regardless if its contained within a box with a background colour.

                                  Preflight is about output checking and my image wouldn't output as black only. I doubt Adobe sees this as a bug so you could file a feature request. Maybe a flag for colorized grayscales and bitmaps

                                  • 14. Re: Indesign CS6 Not picking up grayscale images in preflight check?
                                    rob day Adobe Community Professional & MVP

                                    and manually preflight it

                                    I'm curious what do you convert the grayscales to? Do you print them as CMYK quadtones?