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Still converts Black only to 4/C


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1 minute ago, walt.farrell said:

As I said, the K Only support/option seems to currently be only in Designer, and possibly only in Designer for Windows. As Publisher clearly has the same issue, I expect we'll see that support in Publisher in an upcoming beta release, too.

This bug has been there over many versions. Considering it's a key issue one would have expected it to be dealt with by now.

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7 minutes ago, gordo said:

This bug has been there over many versions. Considering it's a key issue one would have expected it to be dealt with by now.

Considering only Publisher, which is the subject of this topic, the problem has never existed in a released version, but only in beta versions of a new product :)

(And considering "key" issues, each of us has our own list of which issues are key, based on our own personal needs.)

Considering the full range of Affinity applications, it may have been there over many versions, but I have no information on when was it first noticed and reported to Serif. It may have been reported only recently, for all I know. (On the other hand, there are many old, reported bugs, which Serif is working on using their own prioritization scheme and timetable, and balancing their available resources between fixing old problems and doing new development. Not all of the bugs can be fixed as quickly, or with the priority, that all users would prefer.)

-- Walt
Designer, Photo, and Publisher V1 and V2 at latest retail and beta releases
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  • Staff

The K only box is related to images only, essentially allowing you to output them to 1 channel. The issue you're encountering Gordo (at least I think it is) is that your Outer Shadow colour has not been saved as K only - the file attached in the first post is Rich Black.

Now I will say there is a known issue that the colour model drop down in the Filter Effects dialog doesn't show the selected colour model - this is a known issue that is with development. I wonder if this has lead to some confusion and has incorrectly changed the colour along the way.

See my attached video - I've opened your file, and the Filter Effects colour swatch (not the values) definitely shows a Rich Black. If I then switch this to CMYK and change to K only, outputting to PDF is definitely going out as K only.

Could you attach a video showing your export process please, as you've said earlier on in the thread doing that doesn't work for you.

Thanks!

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I think I know what the problem may be.

Although the PDF has an embedded  profile it does not have a rendering intent embedded (I believe that InDesign calls this "Output Intent Profile Name")

When Acrobat opens the PDF it expects to see a rendering intent (likely true for many RIPs). If it does not see the rendering intent then it simply ignores the embedded profile and assigns an arbitrary profile and 100K gets rendered as a 4/C rich black.

Depending on how a prepress RIP is set up, you will either correctly get 1 black plate or you will incorrectly get 4 plates (one for each of the colors in the now rich black)

PhotoShop (a simple RIP) opens the Publisher PDF and displays it correctly as a CMYK file with image content only in the K channel.

Affinity Photo, on the other hand, opens the PDF and displays it as a CMYK file with image content in all channels. I.e. Affinity Photo converts the one color (K) PDF into 4/C (rich black)

I can't see a way in Publisher to embed the rendering intent (as can be done in InDesign) which would eliminate the issue.

So this lack of ability to embed the rendering intent will be problematic in production with folks getting unpredictable results.  :-(

 

 

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9 hours ago, gordo said:

I think I know what the problem may be.

Although the PDF has an embedded  profile it does not have a rendering intent embedded (I believe that InDesign calls this "Output Intent Profile Name")

When Acrobat opens the PDF it expects to see a rendering intent (likely true for many RIPs). If it does not see the rendering intent then it simply ignores the embedded profile and assigns an arbitrary profile and 100K gets rendered as a 4/C rich black.

Depending on how a prepress RIP is set up, you will either correctly get 1 black plate or you will incorrectly get 4 plates (one for each of the colors in the now rich black)

PhotoShop (a simple RIP) opens the Publisher PDF and displays it correctly as a CMYK file with image content only in the K channel.

Affinity Photo, on the other hand, opens the PDF and displays it as a CMYK file with image content in all channels. I.e. Affinity Photo converts the one color (K) PDF into 4/C (rich black)

I can't see a way in Publisher to embed the rendering intent (as can be done in InDesign) which would eliminate the issue.

So this lack of ability to embed the rendering intent will be problematic in production with folks getting unpredictable results.  :-(

 

 

Thanks for getting back to me Gordo,

I've just looked at this Output Intent option in InDesign and it is only for PDF/X formats. I've done a text export using PDF/X-4 preset and it gives the Output Intent profile (listed under the Simulation Profile in Acrobat) as the one you're using, so we do output this, but only where it is valid in PDF/X formats.

Watching your video you've made a document using U.S. Sheetfed Uncoated v2, but then using the simulation profile in Acrobat of U.S. Sheetfed Coated v2, this is why it is happening in the video. Changing this Simulation Profile to the profile used in the document is giving the correct results. 

With regards to Photo I only get the 4 channels if I enable 'Convert opened files to working space' in Preferences > Colour. With this option disabled, opening your PDF in Photo outputs both the text and the image (because the shadow gets rasterised) as K only.

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  • 3 months later...

Hi Affinity,

I've been testing the PDF output capabilities of Publisher and am concerned with what I have found so far as it relates to transparent items.

My test file contains a single image with a black only drop shadow (outer shadow) applied to it and it sits above a rectangle filled with a Pantone spot color.  I watched Gordo's video above and matched his settings.  I am able to get a black only drop shadow if I configure color settings correctly in a couple places but the drop shadow knocks out the spot color below it.  I tried Normal and Multiply blending modes with the same results.  The only way I have found to fix this is to open the resulting PDF in Acrobat and use Pitstop to set the drop shadow to overprint.

Any suggestions?

Thank you,
pd

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1 hour ago, PrepressDork said:

My test file contains a single image with a black only drop shadow (outer shadow) applied to it and it sits above a rectangle filled with a Pantone spot color.  (...) the drop shadow knocks out the spot color below it.  I tried Normal and Multiply blending modes with the same results.  

I can achieve a black only shadow mixing as expected on a spot color with these settings:

– shadow: 100 K global + overprint swatch
– export: PDF/X-1a

v376-1 black shadow no overprint x1a.pdf

It is indeed weird that the overprint option within Export options > More has no effect on the blend look of the K-only shadow. Instead the shadow swatch needs to have overprint assigned. Plus PDF/X-1a.

 

macOS 10.14.6 | MacBookPro Retina 15" | Eizo 27" | Affinity V1

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1 hour ago, PrepressDork said:

My test file contains a single image with a black only drop shadow (outer shadow) applied to it and it sits above a rectangle filled with a Pantone spot color.  I watched Gordo's video above and matched his settings.  I am able to get a black only drop shadow if I configure color settings correctly in a couple places but the drop shadow knocks out the spot color below it.  I tried Normal and Multiply blending modes with the same results.  The only way I have found to fix this is to open the resulting PDF in Acrobat and use Pitstop to set the drop shadow to overprint.

The likely issue, if one looks in Acrobat, is that the shadow object is not set to multiply blend mode.

12 minutes ago, thomaso said:

I can achieve a black only shadow mixing as expected on a spot color with these settings:

– shadow: 100 K global + overprint swatch
– export: PDF/X-1a

v376-1 black shadow no overprint x1a.pdf

It is indeed weird that the overprint option within Export options > More has no effect on the blend look of the K-only shadow. Instead the shadow swatch needs to have overprint assigned. Plus PDF/X-1a.

Your file using /X-1a format is simply creating a bitmap copy of where the shadows sit on the color. That's why it appears to work.

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26 minutes ago, MikeW said:

Your file using /X-1a format is simply creating a bitmap copy of where the shadows sit on the color. That's why it appears to work.

Hm? Yes. So what? – PDF/X-1a does not support transparency (which is necessary to multiply the shadow). So it has no other choice than flattening to bitmap. And it works, doesn't it?

More disturbing is, that AfPub only can export a K-only shadow, multiplied, correct if flattened – and not as PDF 1.7 for instance, which does support transparency.

macOS 10.14.6 | MacBookPro Retina 15" | Eizo 27" | Affinity V1

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1 minute ago, MikeW said:

It doesn't take a new swatch set to overprint in order to obtain the result when flattening transparency.

Hm? You sound a bit fast shooting with your one-liners. – Do you mean in theory of PDF – or in practice in AfPub?

My recent experience is that it needs a swatch set to overprint. The attached PDf from above shows
–– left: default shadow black –– center: 100 K, not overprint –– right: 100 K + overprint.

macOS 10.14.6 | MacBookPro Retina 15" | Eizo 27" | Affinity V1

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5 minutes ago, thomaso said:

Hm? You sound a bit fast shooting with your one-liners. – Do you mean in theory of PDF – or in practice in AfPub?

My recent experience is that it needs a swatch set to overprint. The attached PDf from above shows
–– left: default shadow black –– center: 100 K, not overprint –– right: 100 K + overprint.

Oh, APub is broken in this regard (the multiply, overprint issue). Always has been as far as I recall.

Using a swatch set to OP can/does work under certain circumstances but not all. I can make it fail. APub should be honoring the multiply mode, and it isn't.

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1 hour ago, MikeW said:

Oh, APub is broken in this regard (the multiply, overprint issue). Always has been as far as I recall.

Uh, hope no more buttons to suppress issues. 1814513143_k-onlyfill.jpg.e537b84f4e65aaa816ff1101e7d5a9a7.jpg "Press the 'Multiply' botton to make your previous choice for multiply work."

 

 

macOS 10.14.6 | MacBookPro Retina 15" | Eizo 27" | Affinity V1

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The drop shadow should be set to multiply. That should then make a 100%K drop shadow hit a PDF properly. But a drop shadow, even if set to multiply, does not hit a PDF as multiply.

I don't know if any application's drop shadow when set to 100% K ever overprints. All the applications I use set the multiply on the drop shadow and there technically is no overprint in those documents. Xara products can have object-level overprint. Without doing that, the drop shadow hits a pdf like APub does, that is, there is feathering from the objects overlap by the drop shadow (i.e., knocked out). However, setting the shadow to overprint makes it behave like ID, AI, QXP, etc., but uses overprint to accomplish it. But the reality is that in print they will not quite look identical.

Nonetheless, I believe the main issue in Affinity applications (at least as here with APub) is the lack of properly using Multiply for a shadow effect, not the overprint attribute.

I have no idea what your screen shot is trying to show.

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