color shift in pdf export (or print to pdf)

Question

color shift in pdf export (or print to pdf)

I've searched and haven't found this exact topic...

When I convert my Pages file to a pdf, whether it be by export to pdf or different print to pdf options, I encounter a color shift on certain pages. Every first section page includes a gif (logo) and every page has a blue colored divider bar and headers are styled the same color. Now when I view the pdf, the pages that have the gif in them the blue divider bar and the headers appear navy, while the pages without the gif are the normal blue. I see this change in Acrobat Reader on PC and Acrobat on Mac - but NOT in Preview on Mac (everything is the correct blue when viewed in Preview). Any sugguestions?

Macbook Pro, Mac OS X (10.3.9)

Posted on Sep 22, 2006 4:20 PM

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Answer 1

Walt K

Level 4

2,946 points

Sep 22, 2006 5:22 PM in response to Christopher Crogan

Hi, Christopher,

I'm afraid I have no suggestions as to cause or cure of the color shift, but you didn't mention how it printed. If the end product is supposed to be printed (and not viewed on-screen) and it prints okay, you may be able to ignore the on-screen color shift. If the print is off also, I'm sure a better answer is in the offing.

Walt

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Answer 2

Sep 22, 2006 7:49 PM in response to Christopher Crogan

I've done a lot of testing and have discovered that it doesn't matter what graphic format I use. I've tried gif, jpeg, png, and tif - all with the same results. What I really don't understand is how Preview and Safari can correctly render the colors regardless of the graphics on page, while Acrobat and Reader can not. It's beginning to seem more like an Adobe Acrobat/Reader problem than a pdf/pages problem.

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Answer 3

Sep 23, 2006 9:56 AM in response to Christopher Crogan

Some more information - I was wrong before, when the graphic is in jpg format everything works well (except for the jpg, it's a black and white seal and no matter how I set the quality it looks like crap).
I've also noticed that not only is there a color shift in the colored elements, but the text quality is crap also, but only on the pages that have the gif (or png) on them. The fonts appear to have the jaggies, while pages without graphics on them show the fonts crisp at any zoom level. So it's almost as though the pages with the graphics have been rasterized, while those without are postscript (does that make any sense?).

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Answer 4

sashura

Level 1

55 points

Oct 31, 2006 5:25 AM in response to Christopher Crogan

Hi,

I am not entirely sure we're talking about the same problem, but:

- check if your PDFs are RGB or CMYK. Colour shift happened with my files after CMYK conversion. I solved this by preparing CMYK pdfs myself. Before that I had to sit with my printer and check that colours on CMYK proofs he prepared were ok.
- check DPI (ppi) settings in Acrobat. Using higher DPI settings - I went up from standard 300 DPI to 2400 DPI - helps getting crisper images AND text.
- are you converting straight to PDF or via PS? I found, by trial and error, that going through the PostScript stage ('Print' - Save as PostScript - Open or Create PDF in Acrobat) gives better results than converting straight to PDF.
- Adjust your settings with ColorSync utility. Frank on this forum has posted several times a solid description of this method. I wrote (mostly for myself to remember what I had been doing) a description of the problem and the solution on http://i-work-in-pages.blogspot.com.

I hope this helps.
Alex

iMac, iBook Mac OS X (10.4)

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Answer 5

Nov 2, 2006 8:58 AM in response to Christopher Crogan

Hi Christopher,

If you use Adobe Acrobat Distiller to write your PDF's rather than the MAC OSX system, you will have a lot more control over many things including colours, compression, and resolution. I also suggest you keep the default resolution at 2400, also don't downsample the graphics. Apply JPG Compression (you decide how much), but do not downsample the images.

Gifs are traditionally not used this way, I suggest Jpg's will and should work. Look at the save options when creating the Jpg's.

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Answer 6

Nov 6, 2006 10:57 AM in response to sashura

Alex, most of the time, writing a PS file and distilling it is fine, but there are things that PS don't support and PDF does. Transparancies for instance: A .PS file will flatten the transparancy for print purposes, while a PDF will keep it's transparent nature.

Also, writing a PS file using PMS or spot colours, will convert the colours to its process equivalent. Although the colour data is retained, you would have to convert them back to spot either in the PDF or at the RIP/Render Stage.

There are ways to write a PS file and keep the spot colours (DeviceN) - Quark/Indesign do this well, but I'm not sure about Pages.

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Answer 7

Sep 22, 2006 5:43 PM in response to Walt K

Hi Walt, thanks for the response, but it will primarily be a screen file...

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Answer 8

Joe Lv

Level 1

14 points

Oct 28, 2006 1:32 AM in response to Christopher Crogan

I'm encoutering the same problem. When viewing the converted pdf on pc; pages with png images have stronger font color, while the rest look like ****.

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