Join James Wamser for an in-depth discussion in this video Converting from RGB to CMYK during PDF export from InDesign, part of InDesign CS5: Print Production Guidelines.
In a previous movie, we looked at how we can use RGB images in our InDesign documents. Now, we're going to take a look at how we can convert those RGB images into CMYK when exporting a PDF. I'm going to go ahead and look at my Links panel to see how many RGB images I have in my document. When I go to my Panel Options, I can click next the Color Space, and I can see the color space for every object. In this case, I notice that they are all RGB. Now unless my printer is familiar with working in an RGB-color-managed workspace, I'm going to want to export this as a CMYK document.
To do that, I'm going to choose File, and I'm going to go under Adobe PDF Presets and choose Define. Now a great one to use for a PDF workflow and converting to CMYK is PDF/X-1a. Although this flattens your images, it also converts them to CMYK. Let me go ahead and click New, so we can look at those settings in more detail. The setting I'm most concerned about when converting from RGB to CMYK is Output. In there, I can see Color Conversion, Convert to Destination (Preserve Numbers).
Now in a very early version of InDesign Preserve Numbers was not included, and a lot of people saw their black text changed into four-color. I would use Convert to Destination (Preserve Numbers) for my color conversion. The next thing I would do is for Destination, I would pick Document CMYK. I'm going to go ahead and say OK, and I'm going to export this two-page spread. When I do that, I can look at it in Acrobat. Now, I'm in Adobe Acrobat, and I notice I have single-page PDFs, which is what I want to hand off to my printer.
I also want to hand off CMYK images. One of the ways we can tell if our images are CMYK or RGB is by using Preflight. I'm going to go ahead and look under Advanced > Preflight, and one way I can check is by using list objects using ICC/Lab/calibrated color. Next, I'm going to hit Analyze and see if there are any problems. I have no problems found in this document, which indicates I have no non-CMYK images. So as we can see, an RGB workflow is very practical, but you may want to convert to CMYK when exporting a PDF.
As long as you choose the correct settings, conversion is no problem.
- Understanding facing pages versus non-facing pages
- Creating a gatefold layout
- Loading and embedding profiles
- Understanding overprint vs. knockout
- Understanding mixed inks and registration
- Setting up multiple versions of a document with conditional text and GREP
- Avoiding common font problems
- Understanding RGB and CMYK