Converting to CMYK?

Question

I made a brochure in Pages that I'm having printed. I saved the file as a PDF to send to the printer, and unfortunately he tells me that it's in RGB, so the blacks will look quite bad once printed.
So the question is, how do I convert this to CMYK, the necessary format? I tried saving it as a PDF, then editing the PDF in photoshop to be a CMYK file, but the type remains in process, so that was hopeless.
I'd appreciate any ideas.

Answer 1

So the question is, how do I convert this to CMYK, the necessary format?
Always, always, always use the PDF/X-3 filter in the Apple ColorSync Utility to set up a filter for the particular printing process you will be producing. Save your filter and simply select that filter when you wish to use the same printing process again.
Technically, your question is in a sense non-sense. Look at it this way. What you want is that a photographic object is converted from a three component/three channel colourant model to a four component/four channel colourant model. Let's call the input colourants red, green and blue and lets call the output colourants cyan, magenta, yellow and 'key' which we will write instead of black.
Having said that, we haven't said anything about the colour of the red component, the colour of the green component, or the colour of the blue component on the input side, and we haven't said anything about the colour of the cyan component, the colour of the magenta component, the colour of the yellow component, or the colour of the key/black component.
If we don't say anything about the colours of these components, and their primary, secondary and tertiary combinations, then we have no idea what colours will be formed when these colourants are imaged on different configurations of the colour devices in our workflow. The magenta colourant could come out very, very, very different on an studio printer and a shop floor press.
What we need to know is what colours a specific colour device in a specific configuration (inks, toners, waxes, papers) and a specific calibration is capable of forming, and then we need to characterize that with a colour test chart. We also need to calculate a set of tables that will give us the amount of colourant that reproduce the colours that colour device is capable of forming.
Finally, we need to tinker a bit. We want the sheets of the press to dry fast, so we add K where CMY are neutral throughout the colour space. We want the shadows to retain hue and saturation detail, so we have a soft clipping that opens them up and we take care not to take out too much CMY which would loose us the colour contrasts. And so forth.
Therefore, there is no such beast in the wide world of managing colour information as the beast called 'CMYK'. First of all, it could be that the laydown order is Y first and not C first, and only the characterization for the intended printing condition will know what colours are formed if Y is first and not C. Then there are the lightness levels available for the printing condition - pick the wrong characterization to convert into and you may loose ten or fifteen lightness levels out of a hundred possible. And that is not to speak of the tint of the printing paper for which your characterization will compensate to neutral, if you pick the correct characterization.
So, find yourself a professional printer, propose a colour managed printing process, ask for the correct ICC press profile and plug that into the OutputIntent dialog in the PDF/X-3 filter, then plug the information on the areas outside the page dimensions proper used by the printer's process for bleed and trim, and plug in the printer's specification for flattening of transparency (if you have any).
/hh