Equivalent PDF Export options for InDesign "Convert to Destination (preserve numbers)" Option

[Ken Hjulstrom]

Hi,

My organization is switching to a new print shop, and the new print shop has provide the following information regarding how I should prepare the PDF document for submission:

"only thing I would suggest is exporting the PDF with Output set to "Convert to Destination (preserve numbers)" and use the "US Web Coated (SWOP) v2" color profile"

I'm currently using the following Export options, which work well for our current print shop:

• Compatability: PDF/X-4
• Color Space: As Document
• Profile: Use document profile
• Convert image color spaces: Unchecked
• Honor spot colors:  Checked
• Overprint black: Checked

I'm assuming that I should set the "Profile" export option to be "US Web Coated (SWOP) v2", but what combination of the other settings are equivalent to the InDesign "Convert to Destination (preserve numbers)" specification?

Thanks!

Ken

 

 

I know that my "Profile" export option 

[thomaso]

26 minutes ago, Ken Hjulstrom said:

what combination of the other settings are equivalent to the InDesign "Convert to Destination (preserve numbers)" specification?

This export option does not exist in Affinity. As workaround you could adjust the document's colour setting before export: In the Document Properties -> Colour select the required profile + activate the button "Assign" + confirm "OK". Then in the export dialog keep colour space & profile set to "… Document …":

• Color Space: As Document
• Profile: Use document profile

Unfortunately, the lack of this InDesign export option also means that you can't create an Affinity export preset with this required settings.

[lacerto]

One crucial question related to use of export time color profile change is the purpose the conversion is wished to be used, and whether there are placed CMYK images involved. In InDesign "Convert to destination (preserve numbers)" allows export-time conversion of placed CMYK images with embedded or individually (in context of layout) assigned profiles, making it possible e.g. to repurpose a job inherently designed for coated paper to be used in newsprint (with recalculated TAC values). "Preserving numbers" would in such cases allow recalculation of placed CMYK content with conflicting color profiles, while keeping the native CMYK definitions (in text and shapes). 

Reassigning the document with an alternative color profile within Affinity Publisher (using File > Document Setup > Color) does allow "preserving numbers", but there is then also no way to export and recalculate color values of placed CMYK image content (since it will be done only if there is a conflict between the document and target profile). This kind of need, however, is today pretty marginal since the placed image content should ideally be in RGB color mode, in which case colors would be converted correctly to repurposed target whenever exporting to CMYK (while keeping the current document color profile).  

[lacerto]

A few further notions:

• Compatibility: PDF/X-4 => This is basically in conflict with a recommendation of converting to target color space (whether preserving or not existing color values) since PDF/X-4 by default allows mixed color modes and e.g. in InDesign the default is that colors are not converted but kept, and all involved profiles embedded. So at least check what PDF standard (X-mode) your new printshop recommends, if any...
• Color Space: As Document => Assuming that your document color space is CMYK
• Convert image color spaces: Unchecked => This option is the closest to what InDesign's "Color Conversion" option does: if conversion is used, at all, all RGB images will be converted to target CMYK color space, so in this context this option should be checked.

[Ken Hjulstrom]

Hi lacerto,

Thank you for the detailed information.  Since I don't have direct contact with the new print shop representative, it's a bit difficult to get any more parameters from them than the one I posted here intiailly, but I used a "Compatibility" value of PDF/X4 for the current print shop, so I'm going to stick with that unless the new print shop has a problem with that setting, at which time I'll be able to work with them directly to sort out any parameter issues.  I'm preparing a magazine that contains articles from a variety of authors, and most of the submitted articles are accompanied by image files that come from all sorts of sources.  I don't believe, though, that any of the images particularly contain CMYK colors, and I use Affinity Photo to convert all submitted image files to TIFF for inclusion in the magazine file.  I'm not sure if this conversion guarantees that all of the image files will contain RGB colors only, though.

Your comment about PDF/X-4 not converting color spaces led to something interesting in my Publisher Export dialog.  As I stated in my initial post, I've been using PDF/X-4 Compatibility, and with the "Convert color spaces" checkbox unchecked.  Just for fun, I tried checking that box while I still had the PDF/X-4 compatibility specified, and clicking on the unchecked checkbox had no effect, which makes sense to me, if PDF/X-4 doesn't support color space conversion.  I then switched the compatibility to "PDF/X-3 2003", and I was then able to check the "Convert color spaces checkbox".  But I then switched the compatibility setting back to PDF/X-4, expecting that the "Convert color spaces" checkbox would once again become unchecked, but to my surprise, it remained checked!  I then unchecked that box, and I was unable to check it after that.  A UI bug, perhaps?

Thanks again for your help,

Ken

 

[lacerto]

On 1/5/2024 at 4:20 AM, Ken Hjulstrom said:

 A UI bug, perhaps?

Seems so. On Windows (at least the latest version of Publisher) the check box is available.

Note that within Affinity apps the native objects (shapes and text) are always converted to CMYK when exporting to PDF (in contrast of e.g. InDesign, where you can leave them as RGB as per relaxed specs of PDF/X-4).

So if you do not have the color conversion option checked, you will get this (placed RGB images are left unconverted):

...and if you do, you will get this (placed images converted to CMYK, as well):

As you mention that you typically have material from multiple sources, it is good to know that Affinity apps have serious issues with all PDF/X-based standard export methods, since they do not support passing through non-PDF/X-based PDFs, at all, disregarding their PDF version number, so what happens is that these files will be rasterized [You would need to let Affinity app interpret these kinds of files to avoid that, but then you take risks of having replaced fonts, ignored print settings, and misinterpreted/inaccurately rendered objects.]. 

In this sense, using the default export method (PDF (press-ready)) with PDF 1.7 compatibility level would be most compatible as it has no problems passing through any PDFs. All PDF levels starting from 1.4 allow mixed color spaces and live transparencies so PDF/X-4 is not anything special in this respect. But if you do not mind rasterizing (especially if you can afford exporting at e.g. at 600 DPI), then PDF/X-4 is basically "problem-free".

You should also be aware of the fact that Affinity apps do not convert the color space of PDF content that is defined to be passed through (the default setting), so if you have RGB based PDFs, they will be left in RGB color mode when you export to press-targeted PDF even if you explicitly export to CMYK color space and force conversion of image color spaces (unless being rasterized, in which case they will be converted). This, too, is something you (or printshops) would not expect in light of having experience with other page layout apps (so instructions you get from printshops related to color conversions do not necessarily produce what is expected). 

[Note: In the screenshot above the color definition RGB 255, 255, 255 is of course wrong; the actual definition for the rectangle is obviously RGB 255, 0, 0, while the text  is RGB 255, 255, 255.]