BearofBearsden

My printer now tells me that I have been mistaken, that output of B/W photos from ID will open as Greyscale only in Acrobat, and so need not be changed at all. I have checked and found this to be true, under Output Preview. It is a bit unfortunate that soft proofing in Affinity Photo yields a darker result than now in Acrobat, but if he is right I should be able to go ahead and somehow adjust those photos as are outstanding. So maybe I need not trouble you further. I'll know after seeing the paper proofs. [ Is this automated preflight that rejects the produced PDF file? I'm afraid I don't understand 'automated'. I go into Acrobat Pro 9 'Convert Colours', and have discovered that every output from (my #4) Indesign, that enforces only a CMYK environment, remains a colour file as shown under Output Preview: view CMYK / Grey / Profiled Grey etc. – except when I convert that into Greyscale 2.2 (or make it darker, probably now unnecessarily) under Dot Gain 10%, or whatever. Can you place a sample file of a rejected file here on the forum (or directly to me using a private message) so that I can have a look on the file? Thank you. I'll do so as soon as I have spoken to my printer and got some relevant information. The prime options that I can offer him are: 1) Export from ID and do nothing in Acrobat, in which case the pdf looks much paler than in ID with Preview switched and Imitate Black. But only sometimes.I can find no reason behind these variations. 2) Export and change in Acrobat to Greyscale of one sort or another. Should I Embed too, I imagine? 3) Convert Colour in Acrobat to PSOv3 Coated, as requested by the printer – although Output Preview tells me that this is now a CMYK file again. Do you have the Adobe Dot Gain profiles? I would use those instead of of Gray Gamma 2.2 as that is a display profile and you could not get images produced with that profile darker using Adobe Acrobat Pro profile based color conversion and the same profile. I used Dot Gain 10% a couple of times on a print PDF to make images that where initially produced with Gamma 2.2 (same as D50) darker and more contrasted. I no longer think that this should be necessary,since the Grey 2.2 pdf looks as I expect. I must learn what problem the printer is facing. My sincere thanks again for your trouble.

@LagartoThe problem rolls on. Help again please! My book images are now all rebuilt from the originals as Greyscale 2.2 (= D50 in darkness), imported then into InDesign #4 (an old copy, I know, that only offers a CMYK environment – and output!). Then, as you have recommended, I convert them in Acrobat Pro 9. The question now is How please, since my printing firm, that outputs under PSO Coated v.3, still reports errors. (I have yet to understand what these are.) In Acrobat > Convert Colours, it seems to make little difference whether or not I Preserve Black, and when I output into Greyscale 2.2, the saved pdf looks the same as my ID output (that is pretending that all grey images are still CMYK). This is what I want to see in print (Black ink only). HOWEVER, if I convert the ID pdf instead into PSO Coated v.3 (or if I reconvert the first Grey 2.2 pdf back into this), the Document Output Preview tells me that all output has been reconverted into a CMYK file. Nothing shows up under 'Grey'. The printer, however, is using only black ink, as expected, for the whole book. So the question again is, please, what exact settings should I use in Acrobat > Convert Colours to produce prints that are not too pale, but emerge as Grey (2.2) and not as CMYK, for a printing press that operates black ink under PSO Coated v.3? My thanks again in advance.

This is fantastically helpful, and I'll try to follow it in the morning. I think that before committing the whole lot, I'll just send in a few of the most challenging individual pics for cross-proofing – for now. Your demonstration of how to do it is appreciated; so much in AP is poorly explained, until you can discover somebody on the Internet who can put things in plain English. My thanks again.

This is most generous of you. I'll study it with care. I have spent the afternoon since we wrote in making tests. As you say, I can see no difference in my output as 2.2 vs. D50. I finally found out in Acrobat Pro how then to output using Convert Colour as 10% or 30%. This was new to me. My printer now tells me that their machine is so good that it imposes almost no dot gain worth talking about (on this silk paper, perhaps). Concurrently these tests show that, from a starting point of Grey 2.2 and PSO v.3 Coated, adding 10% dot gain in Acrobat lightens the tiff-from-pdf by maybe 1% using an eyedropper tool, and adding 30% DG lightens it at the most by 2%. Since the intention is to make the pale greys bolder, I'm doing my best to correct the original, and intend then to send out a few comparison pics for proof printing by adding maybe a 50% Multiply layer. This time anyhow I'm hoping that their initial output may match my intent. This may be a simplistic solution to a printing professional, so excuse me if I'm blundering on. It's so easy to get out of your depth without seeing a paper result. And now I've seen your Acrobat instructions too, I think that is pretty much what I've been doing already in my older version (9), except that I've checked Preserve Black. My sincere thanks again, Graham

Dear Legarto, I am most grateful to you for your detailed reply. I have been working steadily for some days adjusting each photo back to Grey 2.2 (and creating a fresh Tiff), checking (temporarily) with Soft Proof under Relative Col., and tweaking the cental curve a little where necessary. (Some of my pictures are of musicians, everything anyhow in B/W.) I'm afraid that I've lost you in your first paragraph. I've yet to hear back from my printer whether he prints at 20% Dot Gain or whatever. AP does indeed offer a detailed dropdown menu in which I can select CMYK (and did) , so currently nothing is in RGB. It also offers the options of 'Grey D50' or a variety of generic or Adobe 'Gamma 2.2's. I did not see this in my test, but are you telling me please that Gamma 2.2 will produce a less contrasty output than D50? If so, now is the time to change everything, and at least Preferences will allow this as a default every time you reopen an image. But AP offers no access that I can find to control the Dot Gain of its output – whereas PS offers that as a further detailed option when Converting To. If there is anywhere to specify this, I'd be most grateful to learn urgently please. Otherwise, is it correct that AP defaults to a DG of 15%? Para 2: when I output my tweaked Grey files into InDesign, the working mode for the latter offers no Greyscale options, so I leave ID alone as CMYK PSO v.3. Then it's exported under PDF/X4 into Acrobat Pro. (All text anyhow emerges correctly in Black.) At this point I'm afraid I don't understand your Para.2. There are no colours to convert, and i don't know how you would do so anyhow in Acrobat Pro (9). I only created CMYK options in the first place because the Grey results come back too pale. The printer advises that his machine, that handles either, will anyhow print B/W images without colour when they are so profiled. So if the next Grey tests again prove too pale, would you advise that I 1) adjust something I don't yet understand in Acrobat Pro, or 2) adjust Curves or Levels initially in AP, largely by guesswork, or 3) see what happens by adding one or two layers of Multiply? Very many thanks for your trouble.

A little further reading on this Forum since I posted the question has led me to wonder whether the AP Dot Gain is set as a Default to 15%? 1) Is this true, please? 2) Would it indeed produce too pale a result if the printer is using 20% or 30%? 3) Might a simple way to darken my output to match be to create a duplicate Layer in AP, set it to Multiply, and merge them? If so, does anybody know please what % darkening might be achieved, and whether this will be uniform across the spectrum, or, being a percentage, increasingly darken the deeper shades? (The subject of today's ongoing experiments). 4) I read too, helpfully from @Lagarto a year ago, that changing the profile of a picture from Grey to CMYK (or back again) can fool the RIP when outputting. So, rebuilding each image, when possible from the original, but outputting it afresh now in AP as Greyscale 8 bit Gamma 2.2 (or should this be D50, or does it matter?), please advise how I can avoid the same happening again. Thank you. Greyscale test 23-3-21.pdf

I need to ask your urgent help please. My First Edition book that I have published (550 pages) came back with all the B/W images much too light (photos and shaded graphs). My recent paper proofs for the Second Edition also came back too light, so I converted them as a test in Affinity Photo into CMYK, and these black/white images came back as I had visualised them on my calibrated monitor. So I converted the whole book into CMYK (the working space anyhow of ID). Now the printshop has returned a full pdf proof ahead of printing, and somehow their RIP screwed up all the grey levels so that even white graph squares came out as 25% grey. (Why must AP refer to that at '75%' when every other program calculates from Black towards White? Just another instance where some infuriating desire to differ from Photoshop wastes user hours at every step in researching whether there is an answer hidden on the Internet. ) So the printer has insisted that I turn everything back into Greyscale. Easily done, you would think, except that 16-bit Greyscale images exported will not open in InDesign. (I have since read here of numerous other 16-bit Grey problems. Whey have these not been fixed by now? This is supposed to be a professional program. I can open them in Preview or even Elements, but I have abandoned PS with full expectations that AP should work. I have no intention, with limited need, resources and especially time, to abandon hard-won experience in ID to risk a new set of insoluble problems in Designer.) So I have accepted that Greyscale 8 bit will suffice in these limited circumstances. But now I will need to send out new comparative photos for hard proof, for my printer cannot solve the initial discrepancy. Questions: please be so kind as to advise. 1) Does it make any difference to the output (into ID and then into pdf/Acrobat before reaching the printing works) whether I convert back into Greyscale 8-bit under Gamma 2.2 or D50? I have done a comparative test through the first 3 stages, and all pale Greys seem to emerge equal in the pdf / tiff. 2) AP, ID and Acrobat have all been set to identical Profiles: PSO Coated v.3 (for the UK); and all black/white images are being Soft Proofed all under Relative Colorimetric (the internal contrast tweaked somewhat in Curves as necessary). So if the next hard proofs come back paler again than fresh CMYK comparisons (in black/white), the outstanding question can, I think, only be the Dot Gain comparison between the Affinity output and the printer's machine. But although I can and do set PSO v.3 under Colour: Convert Format, Affinity, unlike Photoshop "does not offer Dot Gain". I leave readers to ask why. I have reluctantly resorted to troubling a leading pro photographer at length today, and his final reply was that the best I can do is ask what Dot Gain my printer works to: 20% or 30%. Can somebody please tell me what % Affinity Photo enforces as its Dot Gain output? Then all I could do as necessary would be to darken everything by maybe 10%. How does one even do that uniformly, I wonder? My thanks in advance, (with apologies for cross-posting from an original thread one year after relevance).

I need to ask your urgent help please. My First Edition book that I have published (550 pages) came back with all the B/W images much too light (photos and shaded graphs). My recent paper proofs for the Second Edition also came back too light, so I converted them as a test in Affinity Photo into CMYK, and these black/white images came back as I had visualised them on my calibrated monitor. So I converted the whole book into CMYK (the working space anyhow of ID). Now the printshop has returned a full pdf proof ahead of printing, and somehow their RIP screwed up all the grey levels so that even white graph squares came out as 25% grey. (Why must AP refer to that at '75%' when every other program calculates from Black towards White? Just another instance where some infuriating desire to differ from Photoshop wastes user hours at every step in researching whether there is an answer hidden on the Internet. ) So the printer has insisted that I turn everything back into Greyscale. Easily done, you would think, except that 16-bit Greyscale images exported will not open in InDesign. (I have since read here of numerous other 16-bit Grey problems. Whey have these not been fixed by now? This is supposed to be a professional program. I can open them in Preview or even Elements, but I have abandoned PS with full expectations that AP should work. I have no intention, with limited need, resources and especially time, to abandon hard-won experience in ID to risk a new set of insoluble problems in Designer.) So I have accepted that Greyscale 8 bit will suffice in these limited circumstances. But now I will need to send out new comparative photos for hard proof, for my printer cannot solve the initial discrepancy. Questions: please be so kind as to advise. 1) Does it make any difference to the output (into ID and then into pdf/Acrobat before reaching the printing works) whether I convert back into Greyscale 8-bit under Gamma 2.2 or D50? I have done a comparative test through the first 3 stages, and all pale Greys seem to emerge equal in the pdf / tiff. 2) AP, ID and Acrobat have all been set to identical Profiles: PSO Coated v.3 (for the UK); and all black/white images are being Soft Proofed all under Relative Colorimetric (the internal contrast tweaked somewhat in Curves as necessary). So if the next hard proofs come back paler again than fresh CMYK comparisons (in black/white), the outstanding question can, I think, only be the Dot Gain comparison between the Affinity output and the printer's machine. But although I can and do set PSO v.3 under Colour: Convert Format, Affinity, unlike Photoshop "does not offer Dot Gain". I leave readers to ask why. I have reluctantly resorted to troubling a leading pro photographer at length today, and his final reply was that the best I can do is ask what Dot Gain my printer works to: 20% or 30%. Can somebody please tell me what % Affinity Photo enforces as its Dot Gain output? Then all I could do as necessary would be to darken everything by maybe 10%. How does one even do that uniformly, I wonder? My thanks in advance.