RGB Problem

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    • #71170

      Most of the photos I have are used for printing marketing materials, and every picture file I open is in RBG. I would prefer to open all images in CMYK. Does anyone know where this setting can be changed?

    • #71171

      You need to resave the art in Photoshop as CMYK.

    • #71172
      David Blatner
      Keymaster

      When you say “open” do you mean open in Photoshop? Place in InDesign?

      I rarely convert any images to CMYK anymore in Photoshop. I place them as RGB into InDesign. That is the 21st century workflow. Converting to CMYK should be reserved for the rare image that requires editing in CMYK.

      • #71176

        Well David, if that’s the 21st century workflow, then you should let the book publishers know that. It is CMYK and not RGB, so far as they are concerned. And that’s the book publishers and the printing houses.

        Maybe things are different for magazines or fliers, but in book publishing (at least from the major U.S. ones I work with) it’s CMYK.

    • #71182
      Tom Venetia
      Member

      I am not sure if ID (CS6) would accept RGB images. Clearly the print on demand houses do not (such as CreateSpace and Lulu).
      My logic says that all images should be converted to CMYK and .TIF because that is a Postscript RIP’s natural language.
      Furthermore, with RGB transparency may not be preserved on most digital print devices.
      So answering Ashley’s question, my recommendation would be the same as Dwayne gave, namely convert in Photoshop to CMYK and save in .TIF. This occupies more file space but you will be on the safe side when exporting to PDF for printing.
      Even with grayscale images I do this (save in .TIF).
      David, am I wrong or overdoing?
      Tom

    • #71184
      David Blatner
      Keymaster

      Oh, I’m so glad we’re having this discussion because it reminds me to finish an article on this very subject that I’m writing with Claudia McCue.

      Dwayne: Book publishers are notorious for being very slow to evolve, especially in technology. Printers are second.

      Tom: your logic that ” images should be converted to CMYK and .TIF because that is a Postscript RIP’s natural language” is faulty. Neither CMYK nor TIF are natural languages to PostScript. I’ve been programming in PostScript since 1989, and I can tell you that this is one of those “urban legends” that should be ignored.

      You are totally overdoing. There is NO reason to convert to CMYK in most cases, and there is certainly no reason to use TIF in most cases (as opposed to PSD, or even JPEG!). See https://creativepro.com/tiff-vs-psd-vs-eps-vs-pdf-vs.php

      There are a few cases when converting to CMYK makes sense, but they’re the exception, not the rule. If you ask 10 expert trainers in the field, 9 of them will agree with me and 1 will say “Dang it, we’ve always converted to CMYK, so that’s what I keep telling people to do. Hey, kid, get off my lawn!” And it’s been this way for 10 years.

      Now I need to be clear about one really important thing here: I am not necessarily saying you should send RGB to your printer! I do not send InDesign documents and my images to the printer. I send them finished PDF files. And those PDF files are sometimes CMYK and sometimes RGB. The key is that I let InDesign do the conversion to CMYK (and to the correct CMYK) when I export the PDF.

      There’s nothing wrong with converting to CMYK and using TIFF and all that if you work by the hour or you’re just stubborn and crusty. Or there is some actual scientific reason to do so, which is possible, but unlikely.

    • #71185
      Eugene Tyson
      Member

      I place RGB images into my file.

      On export to PDF I choose the “Convert to Destination (Preserve Numbers)” and select my output destination (whether it’s newspaper, book, magazine etc. and where in the world I’m having it printed.

      This way I don’t have to have versions in RGB, and 5 versions in CMYK – imagine if this was the case and 100s of photos on a project and they wanted the images cropped, cloned, etc. that would be doing the work 6 times for 1 image, or 600 times instead of 100 times.

      I’d much prefer to leave things as RGB and convert to CMYK on the fly.

      As David says, there are exceptions, like being colour critical with a CMYK image – perhaps you need to have white out text over the text, and RGB to CMYK straight conversion gives you 90 Cyan, 100 M, 100 Y and 100 K – I’d much prefer the blacks be toned down a bit so that it’s easier for the printers to reverse out my text.

      Anyway – it’s been a heck of a long time since I did any conversion from RGB to CMYK in photoshop. Let InDesign handle that, I will handle InDesign :)

      • #71187

        David–I agree that the book publishing world is slow to change, especially the printers. But unfortunately for those in the field, RGB is a no-no, though it may be okay elsewhere in other fields.

        We also supply PDFs to the printer. And one of their presets warns us if anything RGB is in there.

      • #71189
        David Blatner
        Keymaster

        As Eugene pointed out, you can convert all RGB data to CMYK when you export the PDF, so you don’t have to worry about that.

        I encourage everyone to check out my title about how to make high-quality PDF files for print here:

      • #71192

        Thanks, David. I’ll check with the powers-that-be at work about converting RGB to CMYK when exporting.

        Sof ar as making high-quality PDFs, we have presets that we have to use from the printing houses. But I’ll check out the video in the next day or two (when I have time).

        Thanks

    • #71197
      Eugene Tyson
      Member

      Test for yourself – I doubt you’ll see any comparable difference in an image that was converted to CMYK in photoshop and an RGB that is converted on the fly from InDesign.

      Just make sure when exporting the CMYK image from InDesign that you have no colour conversion selected.

      On the RGB image – choose Convert to Destination (Preserve Numbers) and choose the same CMYK destination profile as you did in Photoshop.

    • #72169
      David Blatner
      Keymaster

      Claudia and I finally got around to writing this up… why you should place RGB images into InDesign:
      https://creativepro.com/import-rgb-images-indesign-convert-cmyk-export.php

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