Not wanting to be contrary here, but why does the PDF have to be only grayscale, just because it's going to be printed in black and white? Surely the printer driver should be perfectly capable of making intelligent decisions about converting the colours to grey. (And, indeed, it will make better decisions than you can earlier in the chain, cos it will know more about the output device).
I mean, for instance, any domestic or office printer in existence will happily print in greyscale if you feed it a colour file (there's usually a checkbox somewhere in the print dialog). I'm sure most of us do and see this every day. I appreciate some things look better than others when neutered like this (some hues of colour won't give very good contrast against each other in grey) ... but the remedy for that is more in choosing the colours in the first place, not in some fancy 'conversion to greyscale' process. For instance I can't think that green text on an orange background is ever going to be very clear in greyscale, no matter what point in the chain you convert it. David Message: 2 Date: Wed, 11 Dec 2013 21:13:14 +0000 From: Steve Rickaby <srick...@wordmongers.demon.co.uk> To: firstname.lastname@example.org Subject: CMY data in PDF for JPEGs [do have workaround, but just curious] Message-ID: <email@example.com> Content-Type: text/plain; charset="us-ascii" I know I'm using up all my tokens here, but... FrameMaker 7 -> .ps -> Distiller 6 -> PDF. Book contains many JPEGs. Book is to be printed in grayscale, so needs to have no information in C, M and Y channels. JPEGs converted to 256-bit grayscale, using the same workflow as I've used successfully many times before. Developer of graphics editor (Thorsten Lemke, GraphicConverter) looks at JPEG samples and swears they contain no color data (and he should know - he's been developing GC for maybe 20 years). JPEGs inserted into FrameMaker and output as .ps, then distilled. In the PDF, JPEG images have data in C, M and Y channels Anyone have any idea how this could happen? The last time it did, I had to send pre-press files off to someone who had the latest Acrobat for pre-press fixup. Lemke says FrameMaker is putting the color in! Setting the printer driver to output grayscale only does not fix this - although it does map other color such as colored text to the K channel. What does fix it is converting the JPEGs to TIFFs. As my pal in Ohio is fond of saying, 'Go figure!' -- Steve *** Confidentiality Notice: This e-mail, including any associated or attached files, is intended solely for the individual or entity to which it is addressed. This e-mail is confidential and may well also be legally privileged. If you have received it in error, you are on notice of its status. Please notify the sender immediately by reply e-mail and then delete this message from your system. Please do not copy it or use it for any purposes, or disclose its contents to any other person. This email comes from a division of the Invensys Group, owned by Invensys plc, which is a company registered in England and Wales with its registered office at 3rd Floor, 40 Grosvenor Place, London, SW1X 7AW (Registered number 166023). For a list of European legal entities within the Invensys Group, please select the Legal Entities link at invensys.com. You may contact Invensys plc on +44 (0)20 3155 1200 or e-mail recept...@invensys.com. This e-mail and any attachments thereto may be subject to the terms of any agreements between Invensys (and/or its subsidiaries and affiliates) and the recipient (and/or its subsidiaries and affiliates). _______________________________________________ You are currently subscribed to framers as arch...@mail-archive.com. Send list messages to firstname.lastname@example.org. To unsubscribe send a blank email to framers-unsubscr...@lists.frameusers.com or visit http://lists.frameusers.com/mailman/options/framers/archive%40mail-archive.com Send administrative questions to listad...@frameusers.com. Visit http://www.frameusers.com/ for more resources and info.