CMYK images

Hi,

I am pretty new to Indesign CS3 and my printer has asked me to convert all of my images to CMYK... I have over 100 in my document...



I normally send a pdf via File%26gt;Export, is there a quick way to change all of my images from RGB to CMYK?



I also have photoshop if that may speed things up...



Thanks in advance



Alun
CMYK images
Alun,



a conversion by Photoshop offers more control, but you

can do it in the RGB-PDF by Acrobat Pro:



Take care that your global Color Settings are correct:

RGB = known source RGB space for all images

CMYK = defined destination CMYK space for PDF printing



Use Rendering Intent Relative Colorimetric as default.

This is wrong in very rare cases. Then it's necessary

to convert images individually by Photoshop.



Export with No Color Conversion = Colors Unchanged.



Then use

Acrobat Pro %26gt; Tools %26gt; Print Production %26gt; Convert Colors

and choose 'Convert' for all RGB images and 'Preserve'

for CMYK images (if there should be some in the chosen

CMYK space). Embed the CMYK profile as Output Intent.



Execute and Save As by new name (in order to preserve

the RGB-PDF).



Best regards --Gernot Hoffmann
CMYK images
That seems like an extra step, Gernot. What have you got against the ''convert to destination profile'' and choosing the output profile directly in InDesign while exporting?



Peter

Peter,



yes, looks like a good solution. I thought the OP wanted

to convert the PDF.

Then I would Export as PDF/X-1a (with Output Intent) and

the output profile embed once (this choice isn't available

in ID CS2). One has to take care that the Joboptions don't

apply JPEG for photos by default.



Best regards --Gernot Hoffmann

Hi,

Thanks for all this, OK - If I can export and convert to CMYK straight away then that is what I wish to do.



So let's start from scratch a little.



I File %26gt; Export



Standard is PDF/X-1a:2003

Compatability is Acrobat 4(PDF 1.3)



Output

Color conversion = Covert to destination

Destination = Working CMYK (Coated FOGRA27)

Profile inclusion = grayed out



PDF/X

Output intent Working CMYK Coated etc



Do I need to change anything or do I need to check settings in another tab?



Finally, how do I make sure it has worked and all images are CMYK?



Thanks all



Alun

Alun,



in my version CS2 the joboptions PDF/X-1a(2003)

contain indeed compression Automatic(JPEG).

This is bad: use no compression.



You can test the PDF by Acrobat Pro:

Tools %26gt; Print Production %26gt; Preflight %26gt;

PDF/X-1a:2003 compliant %26gt; Execute



Check all features: color spaces, images and

profiles for images etc..

Compliance is indicated globally.



For arbitrary PDFs use DigitalPress(Color) instead

of PDF/X.. as reference in Preflight, for instance for

a master PDF in RGB.



Rendering Intent Relative Colorimetric is recommended

for real world photos. Artificial images like computer

graphics require a further discussion.



Best regards --Gernot Hoffmann

For high resolution digital photos, there is absolutely nothing wrong with JPEG compression. Yes, JPEG is lossy, but if properly used minimal compression / maximum quality with high resolution images you should not see any ill effects for print or display but you will get significant file size savings. If you use compression Automatic (JPEG) / Maximum Quality, JPEG compression is used for images that are photographic in nature and ZIP for other images.



- Dov

Dov,



you're right. But this issue has as well an educational

aspect: if people get used to save as JPEG for critical

work without checking the outcome, then this will end

occasionally in rather bad prints.

For instance color engravings: these are probably not

considered as cases for ZIP by Acrobat's interpreter.

As well not anti-aliased computer graphics.



A test by Photoshop for JPEG compression with maximal

quality for a landscape photo delivered no compression

artifacts and almost no measurable deviations.

But the compression ratio was only 2.8. JPEG with such

a low compression ratio has of course a very good quality.



For other readers: compression ratio = uncompressed file

size divided by compressed file size.



My suggestion:

Save everything either uncompressed or save by ZIP and

apply a PDF optimization either by Acrobat or by Quite

a Box of Tricks individually for each image.

The default should NOT be [Automatic = ZIP but JPEG if

photo-like].



Best regards --Gernot Hoffmann