22 Replies Latest reply on Nov 23, 2008 11:27 PM by (kokii)

    IDcs2 late binding RGB to CMYK

      InDesign CS2 uses two document profiles, RGB & CMYK. I have been using a "late binding" workflow with an Epson R1800 "RGB" printer, letting InDesign convert to the Printer Profile.

      I was surprised I cannot use the RGB document space and let ID Determine Colors for the CMYK Printer Profile for a Phaser CMYK solid ink printer.

      For CMYK printers are my placed sRGB images converted to the CMYK working space of the InDesign file for output, or are they just passed through so I can still allow ID to Determine Colors for Printer Profile selected ?

      Does the same hold true for separations made to film or plates?

      Thanks, Mark
      Mac OS 10.4
        • 1. Re: IDcs2 late binding RGB to CMYK
          Lou Dina Level 3
          Mark,

          First, I work on a PC, so there may be some differences. I have sporadically had problems getting accurate color from IDCS2 when outputting to an RGB printer. I'm not sure why it happens, and nobody (including Adobe) has managed to explain what happens with RGB files sent to RGB devices. So, for that reason alone, I do not recommend using late binding workflows. I think it is an Adobe print engine issue, but they'd deny it no doubt, as they usually do. When the couldn't solve the problem, they just became "unavailable". In theory, when printing from IDCS2, the ID print engine will convert ALL document colors to your intended print space.

          If my final intent is a press or other CMYK based device, I always place CMYK images into ID. I soft proof my final output space while editing in Photoshop, which I trust a lot more than I do ID. By the way, I have not had any problem with CMYK files rendering incorrectly, so that seems to work fine.

          I don't have ID open right now, so I cannot answer some of your specific questions. For proofing on an RGB inkjet device, here is what I do.

          1. Create the entire document in the destination CMYK space, including all placed images. Make sure the ID document itself is set to the same CMYK workspace, and make sure the document blend space is set to CMYK.

          2. For proofing on an RGB inkjet, I first export to PDF, leaving color unchanged. Then I open the PDF in Acrobat and set up my print stream to have the correct printer profiles, etc.

          3. I usually send both the IDCS2 file and the PDF to my commercial printer. This way they have both, just in case there is an issue with the IDCS2 file. And I ALWAYS have them generate a color proof on their inkjet as a contract proof. I like to compare it to my inkjet proof to make sure everything is right.

          I hope this helps somewhat, though it doesn't take you in the exact direction you intended. I think Adobe still has work to do on their program, but perhaps this has been fixed in later releases of ID.

          Lou
          • 2. Re: IDcs2 late binding RGB to CMYK
            Hi Lou

            do you now if this problem fixt in IDcs3 or cs4?

            thank
            • 3. Re: IDcs2 late binding RGB to CMYK
              Lou Dina Level 3
              Kokii,

              I don't know if it is fixed or not. I haven't used either IDCS3 or IDCS4.

              When printing RGB files from ID to an RGB inkjet, sometimes I would get some very strange color shifts. It would often have a pink/magenta cast in the print. It wasn't incorrect settings, plugged nozzles, or anything else. I tried printing with "Preserve RGB Numbers" both checked and unchecked, and both introduced problems. It wasn't a corrupt file either. I checked many times and spent a few hundred hours trying to solve the problem (on two separate computers, with fresh installations of IDCS2). I never had the problem with IDCS1.

              I finally gave up. If I have to proof any ID file on an RGB inkjet, I always export to PDF and then print from the PDF file. That always works for me and the colors match.

              Lou
              • 4. Re: IDcs2 late binding RGB to CMYK
                Level 1
                Thank Lou

                what you meam "RGB inkjet..."? did you mean more 4 ink?

                thank
                • 5. Re: IDcs2 late binding RGB to CMYK
                  Level 1
                  Lou, thanks for your reply. I achieve consistent and accurate using a color managed late binding work flow from all the CS2 applications to my Epson R1800 "RGB" ink jet printer. Same print results using PS, ID & Acrobat tested with photos and a test print with a Granger rainbow, gradients, and 20 step grey scale patterns.

                  I like late binding as the work may be output to different devices & I try to avoid having multiple copies of things targeted to a certain printer or paper. Basically I can keep a single image in the edit space of sRGB, Adobe RGB or perhaps even ProPhoto.

                  My question is in regard to the CMYK printer and the fact that InDesign pulls up the CMYK profile of the document as the source. I was wondering if during printing the application converts the placed RGB files to that document CMYK space or if it is just passed through and the Printer Profile should be used to Determine Colors.

                  I am trying to avoid a possible double application of CMYK profiles. And I am trying to get a handle on this in advance of some volume printing -- the Xerox Phaser solid ink uses a lot of ink just warming up.

                  A common problem with (at least) Epson ink jet printers is double color management causing magenta prints -- occasional if the Epson driver is switching back to a default of color management.

                  But back to the question of this thread. Late binding from IDcs2 to a CMYK printer, when does a conversion to a CMYK space take place during printing -- from the document source, or is it just at the printer profile? I guess it should not be that different an RGB to RGB conversion, so I will assume the latter -- at least for placed images!. It is disconcerting to see the Document Space as CMYK.

                  Mark
                  Mac 10.4, CS2, Phaser 8400 PostScript
                  - - -
                  • 6. Re: IDcs2 late binding RGB to CMYK
                    Lou Dina Level 3
                    Kokii,

                    All printers use CMYK inks, and some use additional inks, such as light cyan, light magent, and even red, green and blue for extended gamut. The "RGB" refers to the data stream that is sent to the printer.

                    If you are using a standard printer driver, the data stream is sent to the printer as RGB data, then the driver converts the RGB data so the printer can print it. "CMYK" printers are usually driven by a RIP, so they expect to receive a CMYK data stream.

                    Lou
                    • 7. Re: IDcs2 late binding RGB to CMYK
                      Lou Dina Level 3
                      Mark,

                      Glad you aren't having the problems I had. I never did figure it out, and I have done this stuff professionally for years. It happened sporadically, but enough to make me find a work-around.

                      I agree that late binding can be very attractive (as long as it works, which it seems to for you).

                      InDesign does NOT convert to the default document space during printing. It uses the default document space to define all "native components", such as text, lines, color blocks and other elements created directly inside of InDesign. Any placed images that are untagged, are assigned the default CMYK or RGB color space (depending on whether they are RGB or CMYK images). Let's assume your default document space is US Web Coated SWOP v2. If you are outputting to US Sheetfed Coated or another CMYK space, then ALL native and untagged elements will be converted to the new CMYK space. If you are printing to US Web Coated SWOP v2, then no conversion will take place, since both source and destination spaces are identical.

                      Placed components with tags, whether RGB or CMYK, will be converted to your destination space if they are different from the source tag. ID looks at each element, one by one, to determine if conversion is required, then converts on the fly as part of the printing process. Tagged elements are handled separately and are not affected by the document default color space.

                      A common problem with (at least) Epson ink jet printers is double color management causing magenta prints -- occasional if the Epson driver is switching back to a default of color management.

                      I always used Epson printers for my proofing, and ALWAYS had color management turned off in the driver, and used custom profiles. I appreciate the info, though.

                      I hope the above answers your questions.

                      Lou
                      • 8. Re: IDcs2 late binding RGB to CMYK
                        Level 1
                        Thank you Lou!
                        • 9. Re: IDcs2 late binding RGB to CMYK
                          Level 1
                          Thank you Lou. I believe I am now clear on the handling of placed images that are tagged.

                          Regarding native components, InDesign color space is then either the document RGB or document CMYK, depending on output sent to the printer.

                          And so in keeping with the ideal of a late binding workflow, one would want the largest CMYK color space for the document.* A web uncoated document printing to a sheet fed coated profile would not be a good idea.

                          Mark
                          - - -

                          * Assuming were are creating far reaching colors from within InDesign. Another question then would be what are the largest CMYK spaces.
                          • 10. Re: IDcs2 late binding RGB to CMYK
                            Lou Dina Level 3
                            Mark,

                            I'm not sure I understood your statement...."Regarding native components, InDesign color space is then either the document RGB or document CMYK, depending on output sent to the printer."

                            I'll clarify to make sure we are on the same page. You can set up ID color settings so you have a default RGB and a default CMYK. This way, when you create a New document, any CMYK or RGB elements you create inside ID will automatically be tagged with the default color space. Same with placed untagged images.

                            You CAN override the ID defaults on a document by document basis. If you do so, then ID will use that default for that document (but when you go to create a New document, it will revert to whatever is in your color settings dialog box).

                            When ID sends output to your printer, it uses the default RGB and CMYK color spaces (or the document color spaces if you chose to override them) as the source for all native elements, and all placed components that don't have a separate tag. If you are printing to your CMYK inkjet via a RIP, there WILL be a conversion to your destination CMYK when printing, if your source space is different (whether RGB or CMYK). If you check the "preserve cmyk color numbers" box during printing, native elements and untagged objects will not be converted. Tagged elements will be converted.

                            Perhaps we are saying the same thing, but I wanted to be clear.

                            I totally agree that a web uncoated document being sent to a sheetfed coated press would automatically shrink your color gamut and dynamic range based on the original.

                            Lou
                            • 11. Re: IDcs2 late binding RGB to CMYK
                              Level 1
                              Lou, my comment "Regarding native components, InDesign color space is then either the document RGB or document CMYK, depending on output sent to the printer." is a bit different than yours "When ID sends output to your printer, it uses the default RGB and CMYK color spaces "

                              Your statement using AND may be the correct one., but only one color space is listed as source, and which one depends on what we are printing to.

                              My file may have color defined in RGB values, but when I go to print the ID print dialog box will only pull up the CMYK document profile if I am sending it to a RIP. Or if going to an RGB printer, only the RGB document space will be listed as source.

                              Thanks, Mark
                              - - -
                              • 12. Re: IDcs2 late binding RGB to CMYK
                                Lou Dina Level 3
                                Mark,

                                That would make sense to me. If the final output is destined to go to a RIP, then ONLY CMYK profiles should be displayed. If the final output will be sent to a print driver, then being an RGB device, only RGB devices should be listed. There is no reason for ID to list RGB profiles if your destination space is a CMYK RIP, and vice versa.

                                This simply means that ALL elements in the InDesign file will be converted to the destination space, whether the ID components are RGB or CMYK, as it should be.

                                Lou
                                • 13. Re: IDcs2 late binding RGB to CMYK
                                  Level 1
                                  Lou, it is *source* that has me wondering what goes on in the process. If my output is CMYK my source must be CMYK.
                                  • 14. Re: IDcs2 late binding RGB to CMYK
                                    Lou Dina Level 3
                                    Mark,

                                    If I understand what you are saying, I disagree. If the output is a CMYK device, your source does NOT have to be CMYK.

                                    During output, InDesign will see that your output device is CMYK, and more accurately, a specific flavor of CMYK, based on the CMYK profile in use (whether it is US Sheetfed, US Web Coated SWOP, or a custom CMYK profile). You can have CMYK and RGB components in your original document, and every single element in your file MUST be converted to CMYK, otherwise it cannot be printed. Your RIP expects a CMYK data stream. So, the InDesign print engine will make those conversions 'on the fly' as it is "RIPPING" the file. BTW, I don't necessarily recommend placing RGB files into ID if you know your output will be CMYK, and I am not a fan of having both RGB and CMYK elements in a file, but it CAN be done.

                                    If I misunderstood what you were saying, ignore what I just wrote.

                                    Lou
                                    • 15. Re: IDcs2 late binding RGB to CMYK
                                      Larry Tseng
                                      Lou & Mark,

                                      What's confusing about ID's print dialog box is that, even though two working spaces can coexist in a document (one rgb and one cmyk), it shows only one source profile: an rgb profile for the source if the destination is rgb, and a cmyk profile for the source if the destination is cmyk. This is unfortunate because it makes you wonder about the other profile.

                                      To check it out, I created an ID document with rgb and cmyk components and printed to a cmyk printer, saving the result as a postcript file to disk. The converted values came out as expected. In other words, ID converted both rgb and cmyk sources to the destination cmyk profile.

                                      Hope this is useful.

                                      Larry
                                      • 16. Re: IDcs2 late binding RGB to CMYK
                                        Lou Dina Level 3
                                        Thanks, Larry.

                                        That agrees with my understanding. Hope all is well at your end.

                                        Lou
                                        • 17. Re: IDcs2 late binding RGB to CMYK
                                          Level 1
                                          Larry, thanks for the reply. ID converted both rgb and cmyk sources to the destination cmyk profile -- but what route did they take? It seems likely that ID internally converts all the elements to the working space that is called up (doing a "mode" conversion on what is needed) and then another conversion to the destination cmyk profile, if different. (sRGB > SWOP > Phaser cmyk). *

                                          As opposed to PhotoShop which will use the sRGB document space and do a mode & profile conversion to destination cmyk profile during printing. (sRGB > Phaser cmyk).

                                          Mark

                                          *A test might be an ID file with large RGB space & a very small CMYK. Elements created in RGB using color that would be clipped, lost, changed, and then printing to a large gamut CMYK profile / device. The same color element replicated in PhotoShop could then be printed using the large RGB space as the source.
                                          • 18. Re: IDcs2 late binding RGB to CMYK
                                            Larry Tseng Level 1
                                            Mark,

                                            > A test might be an ID file with large RGB space & a very small CMYK.

                                            I had the same idea. When I convert the document to a wide gamut cmyk "printer", the conversion path for the wideRGB source appears to be direct, i.e., from wideRGB to wideCMYK -- not wideRGB to smallCMYK to wideCMYK.

                                            Regards,

                                            Larry
                                            • 19. Re: IDcs2 late binding RGB to CMYK
                                              Level 1
                                              Hi Larry

                                              what you mean " wide gamut cmyk "printer"?

                                              thank
                                              • 20. Re: IDcs2 late binding RGB to CMYK
                                                Level 1
                                                Larry, that is a better result than I expected (seeing the dialog box list only a cmyk source profile). The handling you found makes late binding RGB to CMYK a lot less prone to possible accidents when printing from InDesign.
                                                Thanks,
                                                Mark
                                                • 21. Re: IDcs2 late binding RGB to CMYK
                                                  Larry Tseng Level 1
                                                  Kokii,

                                                  > what you mean " wide gamut cmyk "printer"?

                                                  ID's print dialog lets you assign a profile to the printer that you are printing to. Instead of a real profile, I assigned a wide gamut cmyk profile from curvemeister.com for my test.

                                                  http://www.curvemeister.com/tutorials/widegamutcmyk

                                                  The wide gamut output profile allowed me to figure out, from a pdf distilled from the postscript output, which conversion path was taken when I printed to my cmyk printer. (I had selected print-to-file at the printer driver.)

                                                  With ID's cmyk working space set to a small-gamut cmyk profile for uncoated paper, the RGB image that I had used retained most of its vividness, which means that it did not go through a conversion to the small-gamut cmyk profile as an intermediate step. Had it done so, the image would have lost much of its punch due to the very light blackpoint for uncoated paper, and from severe gamut clipping.

                                                  Larry
                                                  • 22. Re: IDcs2 late binding RGB to CMYK
                                                    Level 1
                                                    thank Larry