Very often, after I created an CMYK or RGB advert from InDesign, I need to convert it into a black and white version because of client’s request. unfortunately, Adobe’s InDesign, currently CS4, still does not have any export functionality to save PDF files in grayscale version.

Here is another way to do it, very easy: firstly, open your PDF file which is need to be grayscaled in Adobe Acrobat Pro, then, go to Advanced -> Print Production -> Preflight, on the “Preflight” pop-up window, under “Profiles” tab, click “PDF fixups” menu and chose “Convert to grayscale”, then click “Analyze and fix”, all done, save your black & white version now.

turning colored PDF to grayscale