Publisher CMYK Export to PDF for Printing

[Kurt Wilson]

I'm using Publisher to convert my fully illustrated children's book to CMYK, and export the PDF to the book company for printing. The illustrations are photo quality. I plan to use PDF/X-4 in the conversion and I am showing a screenshot of my export specs. Would you please confirm or correct my settings? Thank you.

[lacerto]

I visited bookbaby.com and even if PDF/X-4 does not require conversion of colors to CMYK, they explicitly advise using CMYK color mode both when using Illustrator and Photoshop (where like in Affinity apps, and unlike when using InDesign, you need to have the document in one or the other color space), so using a non-default PDF/X-4 setting and forcing conversion of color space (meaning placed raster images and images rasterized on canvas), as shown in your screenshot, is the correct choice here to guarantee that you have everything in CMYK color space.

[Note that PDF/X-4 based export basically does not require conversion of color values to CMYK, which can be useful when the printer/service provider (like Amazon) creates screenshots based on delivered print PDFs; this way the screenshots use richer/more saturate colors. Affinity apps however always convert native and vector based colors to CMYK with all press-related exports, including when using any of the PDF/X-based methods, which can cause problems if raster-based images are not converted, showing different colors in screenshots in elements that will have identical CMYK values after the conversion has been done at final rasterization during the print process.]

One point worth checking is that your document CMYK color profile is also Coated GRACol2006. If it is not, defining in this context a specific color profile (rather than leaving the default value "Use document profile") that deviates from the explicit or underlying CMYK document color profile, will perform export-time color conversion where existing color values (including native CMYK color definitions like K100 for text) will be converted.

It is a good idea to check the PDF with a viewer that can read true color values of the exported document (e.g. Adobe Acrobat Pro). In lack of such app you can use Publisher to open the created PDF and check at least that the CMYK values of native objects and text elements have not changed at export.

[thomaso]

Hi @Kurt Wilson, Welcome to the Affinity Forums!

6 hours ago, Kurt Wilson said:

Would you please confirm or correct my settings?

Why / with what aspects? The question is rather whether you like the exported result. If yes, it is fine.

(I personally would not deactivate JPG compression / not choose the resampler Lanczos 3 Non-Separable as a general setting.)

[Kurt Wilson]

16 hours ago, lacerto said:

I visited bookbaby.com and even if PDF/X-4 does not require conversion of colors to CMYK, they explicitly advise using CMYK color mode both when using Illustrator and Photoshop (where like in Affinity apps, and unlike when using InDesign, you need to have the document in one or the other color space), so using a non-default PDF/X-4 setting and forcing conversion of color space (meaning placed raster images and images rasterized on canvas), as shown in your screenshot, is the correct choice here to guarantee that you have everything in CMYK color space.

[Note that PDF/X-4 based export basically does not require conversion of color values to CMYK, which can be useful when the printer/service provider (like Amazon) creates screenshots based on delivered print PDFs; this way the screenshots use richer/more saturate colors. Affinity apps however always convert native and vector based colors to CMYK with all press-related exports, including when using any of the PDF/X-based methods, which can cause problems if raster-based images are not converted, showing different colors in screenshots in elements that will have identical CMYK values after the conversion has been done at final rasterization during the print process.]

One point worth checking is that your document CMYK color profile is also Coated GRACol2006. If it is not, defining in this context a specific color profile (rather than leaving the default value "Use document profile") that deviates from the explicit or underlying CMYK document color profile, will perform export-time color conversion where existing color values (including native CMYK color definitions like K100 for text) will be converted.

It is a good idea to check the PDF with a viewer that can read true color values of the exported document (e.g. Adobe Acrobat Pro). In lack of such app you can use Publisher to open the created PDF and check at least that the CMYK values of native objects and text elements have not changed at export.

Lacerto, thank you for taking the time for this helpful and detailed response. Going back to the Color Space toggle, I have now chosen CMYK in the drop down menu. I will also toggle Rasterize to "Everything."

The Coated GRACol2006 ICC Profile is a preset downloaded directly from Bookbaby, since the book will be printed on glossy paper.

Having so tweaked the export specs, would you agree this should be a successful conversion?

[Kurt Wilson]

17 hours ago, thomaso said:

Hi @Kurt Wilson, Welcome to the Affinity Forums!

Why / with what aspects? The question is rather whether you like the exported result. If yes, it is fine.

(I personally would not deactivate JPG compression / not choose the resampler Lanczos 3 Non-Separable as a general setting.)

Thank you thomaso for your valuable input. It's my printing company I need to satisfy, so being my first time converting and submitting a CMYK PDF, I am learning what it takes for a successful export.

I am curious about your perspective on activating JPG compression.

Also, I thought Lanczos 3 Non-Separable was a superior resampling method.

What are your thoughts?

[thomaso]

17 minutes ago, Kurt Wilson said:

I am curious about your perspective on activating JPG compression.

Also, I thought Lanczos 3 Non-Separable was a superior resampling method.

A PDF without JPG compression does not harm the data, but the PDF file can become undesirably huge. Normally, JPG compression with a quality setting of 85 - 95 is fine and has no visible effect on your print result. If you (or the printer) are not bothered by the file size, then it is also fine without compression.

Lanczos 3 Non-Separable may appear sharpened. Just do a test, look at the result at 100% zoom level + compare it with the original image. If you like it, use it.

[Kurt Wilson]

1 hour ago, thomaso said:

A PDF without JPG compression does not harm the data, but the PDF file can become undesirably huge. Normally, JPG compression with a quality setting of 85 - 95 is fine and has no visible effect on your print result. If you (or the printer) are not bothered by the file size, then it is also fine without compression.

Lanczos 3 Non-Separable may appear sharpened. Just do a test, look at the result at 100% zoom level + compare it with the original image. If you like it, use it.

Very good, thanks again!

[lacerto]

6 hours ago, Kurt Wilson said:

Going back to the Color Space toggle, I have now chosen CMYK in the drop down menu.

Depending on which setting you had there before, please ensure that you still have K100 (and CMY 0) as color definition for all text elements that are meant to be printed in plain black (typically at least the body text):

 

I mention this since if you did have your document already in CMYK color mode but using a profile other than "AVL CMYK 2012 - GRACoL2006_Coated1v2", and you had the default "Convert" option highlighted when you pressed "OK", then all existing color values of the document, including black (K100) for text, were converted to new values, making text elements four-color black. If this did happen, you need to change text back to K100.

6 hours ago, Kurt Wilson said:

I have now chosen CMYK in the drop down menu. I will also toggle Rasterize to "Everything."

If you do have text in your document, I would not do that since that would also rasterize all text, which you most probably do not want. There is no need to change this setting.

Basically when you select PDF/X-4 as the export setting, you do not need to change anything else in the settings than check "Convert image color spaces", which forces conversion of placed and rasterized images to be converted to target CMYK color space.

(The initial note I made as for ensuring that you do not accidentally perform an export-time CMYK conversion is related to having the document already in CMYK color mode but having a profile other than the target color space, in your case GRACoL2006_Coated1v2, selected, as switching to another CMYK profile at export time does the same thing as explicitly converting from one CMYK color profile to another using the File > Document Setup > Color tab with the default "Convert" option enabled.)

[Kurt Wilson]

14 hours ago, lacerto said:

Depending on which setting you had there before, please ensure that you still have K100 (and CMY 0) as color definition for all text elements that are meant to be printed in plain black (typically at least the body text):

 

I mention this since if you did have your document already in CMYK color mode but using a profile other than "AVL CMYK 2012 - GRACoL2006_Coated1v2", and you had the default "Convert" option highlighted when you pressed "OK", then all existing color values of the document, including black (K100) for text, were converted to new values, making text elements four-color black. If this did happen, you need to change text back to K100.

If you do have text in your document, I would not do that since that would also rasterize all text, which you most probably do not want. There is no need to change this setting.

Basically when you select PDF/X-4 as the export setting, you do not need to change anything else in the settings than check "Convert image color spaces", which forces conversion of placed and rasterized images to be converted to target CMYK color space.

(The initial note I made as for ensuring that you do not accidentally perform an export-time CMYK conversion is related to having the document already in CMYK color mode but having a profile other than the target color space, in your case GRACoL2006_Coated1v2, selected, as switching to another CMYK profile at export time does the same thing as explicitly converting from one CMYK color profile to another using the File > Document Setup > Color tab with the default "Convert" option enabled.)

Thank you lacerto. This book has all color text designed into the graphics as shown on the attached sample page, though for future books when the text is black and separated from graphics, your direction is invaluable.

The original document is in RGB mode, since the publication is also an eBook. I have superimposed the Document Setup dialog box on top of a sample page with colored text to show my Color Format is set to CMYK/8, and the Color Profile is the AVL CMYK 2012-GRACoL2006_Coated1v2 for the printed version.

I am also attaching the revised export screen shot to show the entire Document Setup and Export flow for print.

[lacerto]

10 hours ago, Kurt Wilson said:

Thank you lacerto. This book has all color text designed into the graphics as shown on the attached sample page, though for future books when the text is black and separated from graphics, your direction is invaluable.

Ok, I see, then you should do just fine with the settings you have chosen (possibly just allowing JPG compression to avoid overly large file sizes, and if you have very large placed PPI values, allow downsampling but considering Bicubic or Lanczos 3 Separable instead of  Lanczos 3 Non-Separable, which may produce sharpening artifacts).

So, what is mentioned below most likely does not apply in context of your document, but might be useful information to anyone intending to produce to both RGB and CMYK from the same document.

The considerations with inadvertent conversion of CMYK-defined colors would be valid only if you had body text or some other elements that are meant to be printed in black ink only ("K100"). In that scenario, when a document is initially created in RGB mode (using e.g. sRGB profile), the initial document CMYK profile will be determined by settings specified under Preferences > Color > CMYK Color Profile. Users typically have there either the default U.S. Web Coated v2, or some common European profile like Coated Fogra 39, ISO Coated v2, etc.

In this scenario, when exporting from an RGB document using PDF/X-4, Affinity apps force conversion of native and placed vector shapes to CMYK color mode, even if RGB is specified as the export color mode (this is definitely wrong). Images (NOT including placed vector documents) however are kept in RGB if not forced to convert. If you use the default settings, the CMYK conversion will be done based on the underlying CMYK target. However if you specify another CMYK profile (as you did, and used GRACoL_2006Coated, the existing CMYK definitions will have values converted to the new profile, and that involves conversion of K100 to four-color black. So in that scenario, the K100 definitions should be reverted manually, or the conversion should be done as follows (starting from the state when you have the document still in RGB color mode):

a) File > Document Setup > Color: change color mode to CMYK, but DO NOT CHANGE the profile. This (just switching between color modes) will not make any changes in color definitions made in the document (but it does change Pixel layers which would be converted from RGB to CMYK; note that Image layers in raster format would not be touched). 

b) File > Document Setup > Color: change to desired CMYK color profile (in your case "AVL CMYK 2012_CRACoL_2006_Coated1v2"), and make sure that "Assign" option is selected, then press OK. Existing CMYK definitions will not be converted.

But as said, since you do not have K100 definitions, the possible inadvertent CMYK color value conversions would not typically be a concern here (but this could be a problem, if a specific CMYK definition is wanted to be used and the color definition was already done while the underlying "wrong" CMYK color profile was active).

Note however that since you intend to produce RGB exports from the same document (probably in PDF format?), what is mentioned above about PDF/X-4 always forcing export time conversion of native and placed vector colors to CMYK (even when explicitly exporting to RGB), is worth a consideration, so you probably want to use another PDF method when creating your RGB exports. Likewise, the note of conversion of Pixel layers to the document color mode whenever the document color mode is switched is worth a consideration since otherwise switching the color modes may cause incremental deterioration of quality of the flattened raster graphics.

So to be "safe" when producing to both RGB and CMYK color modes when using Affinity apps (specifically Publisher), would be working in RGB color mode with correct final color profiles (the underlying RGB and CMYK being defined already in Preferences before the document was created, or defined at a later stage manually as advised above, by assignment, without having any Pixel layers in the document, to avoid conversion of flattened raster content), and always export with "document" color profiles (active, explicit profile, or implicit underlying), to avoid export time (inadvertent) color conversions. When doing so, it is possible to produce all RGB and all CMYK export documents without changing existing native and vector color definitions (and convert the values only "on-demand", non-destructively, and similarly, force conversion of images (both  placed bitmaps and vector documents) only at request. 

A couple of additional warnings when working with PDF/X export formats in Affinity apps:

a) If you have placed CMYK vector documents (like AI), their color mode is not converted to RGB even if image color space is forced to convert to the specified export color mode (using non-PDF/X based methods however works as expected)

b) If you have placed PDFs intended to be passed through, using PDF/X based export methods is likely to cause files to be rasterized instead, resulting in re-interpreted color values, loss of fonts, loss of spot colors, and loss of overprint settings.

And one final warning: the color modes of PDFs placed to be passed through (the default setting) will not be changed at PDF export (any method), unless pass through fails, in which case rasterization results. So if you plan to produce to both RGB and CMYK with accurate color values, it is a good idea to avoid placed PDFs altogether.

[Kurt Wilson]

 

10 hours ago, lacerto said:

Ok, I see, then you should do just fine with the settings you have chosen (possibly just allowing JPG compression to avoid overly large file sizes, and if you have very large placed PPI values, allow downsampling but considering Bicubic or Lanczos 3 Separable instead of  Lanczos 3 Non-Separable, which may produce sharpening artifacts).

So, what is mentioned below most likely does not apply in context of your document, but might be useful information to anyone intending to produce to both RGB and CMYK from the same document.

The considerations with inadvertent conversion of CMYK-defined colors would be valid only if you had body text or some other elements that are meant to be printed in black ink only ("K100"). In that scenario, when a document is initially created in RGB mode (using e.g. sRGB profile), the initial document CMYK profile will be determined by settings specified under Preferences > Color > CMYK Color Profile. Users typically have there either the default U.S. Web Coated v2, or some common European profile like Coated Fogra 39, ISO Coated v2, etc.

In this scenario, when exporting from an RGB document using PDF/X-4, Affinity apps force conversion of native and placed vector shapes to CMYK color mode, even if RGB is specified as the export color mode (this is definitely wrong). Images (NOT including placed vector documents) however are kept in RGB if not forced to convert. If you use the default settings, the CMYK conversion will be done based on the underlying CMYK target. However if you specify another CMYK profile (as you did, and used GRACoL_2006Coated, the existing CMYK definitions will have values converted to the new profile, and that involves conversion of K100 to four-color black. So in that scenario, the K100 definitions should be reverted manually, or the conversion should be done as follows (starting from the state when you have the document still in RGB color mode):

a) File > Document Setup > Color: change color mode to CMYK, but DO NOT CHANGE the profile. This (just switching between color modes) will not make any changes in color definitions made in the document (but it does change Pixel layers which would be converted from RGB to CMYK; note that Image layers in raster format would not be touched). 

b) File > Document Setup > Color: change to desired CMYK color profile (in your case "AVL CMYK 2012_CRACoL_2006_Coated1v2"), and make sure that "Assign" option is selected, then press OK. Existing CMYK definitions will not be converted.

But as said, since you do not have K100 definitions, the possible inadvertent CMYK color value conversions would not typically be a concern here (but this could be a problem, if a specific CMYK definition is wanted to be used and the color definition was already done while the underlying "wrong" CMYK color profile was active).

Note however that since you intend to produce RGB exports from the same document (probably in PDF format?), what is mentioned above about PDF/X-4 always forcing export time conversion of native and placed vector colors to CMYK (even when explicitly exporting to RGB), is worth a consideration, so you probably want to use another PDF method when creating your RGB exports. Likewise, the note of conversion of Pixel layers to the document color mode whenever the document color mode is switched is worth a consideration since otherwise switching the color modes may cause incremental deterioration of quality of the flattened raster graphics.

So to be "safe" when producing to both RGB and CMYK color modes when using Affinity apps (specifically Publisher), would be working in RGB color mode with correct final color profiles (the underlying RGB and CMYK being defined already in Preferences before the document was created, or defined at a later stage manually as advised above, by assignment, without having any Pixel layers in the document, to avoid conversion of flattened raster content), and always export with "document" color profiles (active, explicit profile, or implicit underlying), to avoid export time (inadvertent) color conversions. When doing so, it is possible to produce all RGB and all CMYK export documents without changing existing native and vector color definitions (and convert the values only "on-demand", non-destructively, and similarly, force conversion of images (both  placed bitmaps and vector documents) only at request. 

A couple of additional warnings when working with PDF/X export formats in Affinity apps:

a) If you have placed CMYK vector documents (like AI), their color mode is not converted to RGB even if image color space is forced to convert to the specified export color mode (using non-PDF/X based methods however works as expected)

b) If you have placed PDFs intended to be passed through, using PDF/X based export methods is likely to cause files to be rasterized instead, resulting in re-interpreted color values, loss of fonts, loss of spot colors, and loss of overprint settings.

And one final warning: the color modes of PDFs placed to be passed through (the default setting) will not be changed at PDF export (any method), unless pass through fails, in which case rasterization results. So if you plan to produce to both RGB and CMYK with accurate color values, it is a good idea to avoid placed PDFs altogether.

10 hours ago, lacerto said:

 

10 hours ago, lacerto said:

 

 

Edited May 24, 2022 by Kurt Wilson
Posting error

[Kurt Wilson]

1 minute ago, Kurt Wilson said:

Very good, thank you, lacerto. I will switch to Bicubic and proceed with the submission to the printer. Thankfully, there are no placed pdf's in this document.

The next book will most likely include full color illustrations and K100 black type. So to reiterate, in an RGB Document Setup scenario that will be converted for CMYK print, whenever I enter type in the creation process, I should manually select the type and adjust the color values C-0, M-0, Y-0, K-100 on each page, before the PDF conversion. Correct?

But I need clarity: even if I do so, what setting will prevent the black type from being converted to CMYK in the PDF export process?

Also, what PDF conversion method do you recommend for RGB eBook exports?

 

 

[lacerto]

8 minutes ago, Kurt Wilson said:

The next book will most likely include full color illustrations and K100 black type. So to reiterate, in an RGB Document Setup scenario that will be converted for CMYK print, whenever I enter type in the creation process, I should manually select the type and adjust the color values C-0, M-0, Y-0, K-100 on each page, before the PDF conversion. Correct?

The first step would be making a decision on how (by which printer) the book will be printed. Some printshops use RGB workflows and want to have everything in sRGB, which in many ways is the easiest (and sometimes also the best) method to produce both for RGB and CMYK. The black text is then specified in RGB 0, 0, 0 and the printshop has routines to convert such text to K100 whenever needed.

But if you know that your printer requires CMYK exports, and you know the target CMYK color profile right from the start, and plan to produce both RGB and CMYK versions, I would first create a CMYK document with the correct CMYK color profile, then switch immediately to RGB mode (typically using the sRGB color profile). This way you have the correct document color profile pair so you do not need to specify a non-document color profile at export time that would cause inadvertent conversion of color values defined in the document, nor would you need to perform the kind of color profile assignments that I described in my previous post.

Keeping the document in RGB color mode and defining colors for native objects (vector shapes) in RGB is also useful especially if your book contains vivid colors (which in CMYK color mode would be shown simulating the target CMYK color space and look somewhat desaturated). Direct CMYK values could be used for objects that have recommended CMYK values specified (in the same or near-same CMYK color space, e.g. for "coated papers" if the job is going to be printed on common coated stock, or for "uncoated papers" if it is going to be printed on common uncoated stock; when using "uncommon" print papers, using a recommended (s)RGB value if available and letting the profile do the conversion most often produces the best result).

When working in RGB color mode, it is useful to do reality checks every now and then and export to PDF/X-1a with the underlying CMYK document profile as that export method converts everything to CMYK and also flattens all transparencies. If your document does not have Pixel layers, you can achieve roughly the same if you switch temporarily to CMYK color mode (but do not do this if you have Pixel layers, because they will be converted whenever you make a switch; raster graphics that are in (Image) layers are not affected). Affinity apps have also Soft Proof adjustment but it does not work well, especially not when trying to preview RGB colors with a CMYK target profile.

As for black (body) text, I would initially define it as K100, as that is what is most commonly asked by the printer. It is worth a mention, though, that such text would not automatically be converted to pure RGB black (R0 G0 B0) when exporting to RGB (a thing that e.g. Adobe InDesign would do), but as dark gray (profile-based conversion of K100). Most readers probably would not notice the difference but if you have large black graphic elements, which you want to be deep black both in RGB and CMYK documents, it is best to define them right from the start as R0 G0 B0 (which would then be converted to rich black when exporting to CMYK).

if you want to have K100 in body text when exporting to CMYK, and R0 G0 B0 when exporting to RGB, it is a good idea to tag all such text with styles so that you can switch the text color simply by redefining the style (or use Find Replace searching for style and specifying color change using a formatting option in the Replace clause).

The images (photos, bitmaps) would typically be placed in RGB mode (also when the publication is in CMYK mode), and converted to CMYK if requested by the printer (or if automatically done by the export method, like PDF/X-1a). As for placed vectors (typically in AI or EPS format, or PDF), the implications are more complex, and much depends on whether such documents are 3rd party and how color-critical they are. E.g. AI documents that have embedded and conflicting CMYK profiles would have their CMYK color values converted (something that is typically not wanted), PDFs to be passed through might get rasterized if their PDF versions conflict with that used by the PDF export method, etc.

1 hour ago, Kurt Wilson said:

But I need clarity: even if I do so, what setting will prevent the black type from being converted to CMYK in the PDF export process?

Yes, I can understand. I am afraid this all seems very complex and confusing, and might not be helpful, at all! To be able to give clear instructions, one would need to know the exact details of the production. In a nutshell: in commercial CMYK jobs (offset printing) printers typically expect the body text to be K100 (C0 M0 Y0 K100), and if you define it as such either in an RGB or CMYK Publisher document, and do not change the CMYK color profile at export time (but use the document CMYK color profile), then you will get K100 also in your print PDF (typically produced by using "PDF (press-ready)" or one of the PDF/X-based methods). But as mentioned, K100 text will not be automatically converted to R0 G0 B0 in RGB exports, which may be a problem when you want to produce high-quality RGB books. On the other hand, if you specify R0 G0 B0 as black of the body text, it will be converted to four-color black ("rich black") at export time (or eventually when the printer processes the file)m which is not wanted in small type sizes. Many printers however accept (or even expect) RGB body text as they have routines that auto-convert such text to K100 at print time. So therefore: to be able to tell how to specify black for the text, and whether it is necessary to make manual conversions when producing to different color modes, the exact production specs should be known.

[Kurt Wilson]

Thank you, lacerto. Right now, it's Print On Demand, not offset, if that makes a difference in CMYK conversion specs.

To review, at the initial creation of the document, if I toggle to the correct Color Profile, and select "Assign" in the Document Setup, then manually define all K100 text within the document, and leave "Convert image color spaces" in the Export options unchecked, then the graphics should remain true to color and the K100 text fully black in the final export. Is that correct?

Another curiosity: If I chose for Publisher to Convert placed images to the Color Profile in the Document Setup, but then also told it to "Convert image color spaces" to the same Color Profile in the Export option, is that redundant? Would it cause any problems in the conversion?

[Miltonc]

My offset printers are saying that when the open my cmyk pdf files in acrobat, even though the black is set for overprint, when the remove the black there is still a white 'shadow' of the text on the page.. they are saying that somewhere in the conversion process the black reverts to cmyk. I honestly don't get it

Page 59 B.pdf

[thomaso]

4 hours ago, Miltonc said:

when the remove the black there is still a white 'shadow' of the text on the page.. they are saying that somewhere in the conversion process the black reverts to cmyk.

The two parts of this sentence sound conflicting witch each other. Generally there is either "a white shadow" (= knock out / not overprint) or a "conversion process the black reverts to cmyk". Whereas black text overprint would mean text = 100 K while other colours aren't influenced / don't display the text if K gets disabled.

In your PDF the text gets printed with all 4 inks:

[Miltonc]

Maybe I'm not explaining it correctly, but I can see from your reply that the black is mixed. How do I fix that?