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Consistent colour workflow


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I was on the phone with my  very experienced printer dude. He said that we have inconsistency in colour values. My situation: I create documents for different types of carrier media - mostly coated or uncoated papers. How do I make sure that a certain blue is the same as close as possible on coated as on uncoated paper? The guy from the printershop says that the PDF made in Affinity designer with CoatedFOGRA (CF) 39 has quite different CMYK values than my original file - a certain blue tone has 6% more yellow than the uncoated version which leads to a really different kind of blue.

It is kinda hard to explain in English - (even in German it's not easy for me),. I create a Document in CMYK/UncoatedFOGRA and design a blue shape with the CMYK values 89 56 0 0. With UncoatedFOGRA at PDF-export he gets values of 84.5 53.something 3 0 and worse: with CoatedFOGRA he gets different values and among them 6% yellow which leads to a "complete" different blue. Considering (according to him) that coated paper has per se a yellow tint he (correctly) states that we will end with approx. 12% more yellow which is a galaxy away.

I must admit that I am not the profile pro. My background is multimedia production. In my understanding I design a certain colour and the profiles just make sure that the material it is printend on is taken into consideration. I'm confused and really appreciate any clear and easy advise. If you do have pity with me - please explain it as if I was 9 ;-). Thanks a ton.

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There is a nice discussion a few posts further down about just this topic, for me I recommend staying in the RGB colorspace and let the printer do the grunt work, at best he will strip your ICC profile and replace it with his very own CMYK profile in his Workflow. Without more information it´s hard to say but I would point a finger at a profile or a rendering intent mismatch and his preflight is catching it. Your blue, it would seem is out of gamut for the limited gamut of the ( by now obsolete) Fogra39 profile. 

Check with your printer and ask about supplying RGB, however if you have already created the file in CMYK then stick with CMYK but lose the F39 CMYK profile and ask what  profile he recommends and what rendering intent you should use. As a guess I would start with relative Colorimetric Rendering Intent  as it will force the colors that are out of gamut to the next possible one inside the gamut without changing any color that is within gamut.

I can´t even find a reference for F39 to cross check anymore, so I used the next possible PSO coated V3 and fed it your 89 56 0 0, as you see on the tiny blue dot your color is outside the color gamut of the PSO coated V3. 

Viel Spaß

 

 

icc.jpeg

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7 hours ago, Lagarto said:

This is difficult since exact tones will be determined by paper specs (e.g. dot gain of paper) and if different stock has different paper whiteness it is even more difficult. I am not sure if it is a reasonable requirement even to try to achieve "exactness" (but just reasonable resemblance).

I noticed in your other post that the blueness you are aiming at seems to be based on a PMS definition but produced in CMYK so I am not sure if your problem is not getting close enough with neither either or both coated or uncoated stock. Note that CMYK values for simulating spot colors are only approximations so they might work reasonably well with certain kinds of papers and print standards but less so with others, so if you are otherwise satistifed with colors, your problem might be related to using certain fixed CMYK values for PMS simulation.

There are many kinds of uncoated papers so e.g. "Uncoated Fogra 29" is actually a generic profile for uncoated stock; and there are separate specs for yellowish papers. Many paper manufacturers have specific profiles for different papers for best results and color fidelity and if such are available I would use them (but negotiate first with your printer). If color accuracy is very important, good print proofs would be required to be able to make necessary adjustments. Discuss with your printshop and let them know about your wishes, the problem might be most easily resolved by choosing a bit different stock.

Dotgain or TVI (tonal value increase) as it is now known is compensated for when the press is calibrated, some percentage of TVI is actually required in print.

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35 minutes ago, BofG said:

I would argue that this is the printer's job, not yours. They are running the machinery, they selected the brand of stock they use, they run their calibrations, they should be the ones ensuring their output is as consistent across paper types (and as close to your artwork) as possible.

Well said, in this case, by using F39, the OP has converted his artwork to a colorspace with a limited gamut, if he were to strip the F39 out and replace it with the printers recommendation, THEN let the printer work it out he will have a better chance to reproduce this colour, or as close to it as possible.

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Thanks for all the feedback!

I didn’t know about Fogra being "out of fashion" ;-). The prinshop guy said fogra was fine with them. (I must say, the guy is technical head of one of the largest printshops in Switzerland. They do fantastic and complex work). What I do not understand is that the CoatedFOGRA-profile ads yellow to a paper known for being at the yellow edge by itself... I must say that we didn't have these problems when I did exactly the same in Illustrator. Could it be that the profile from Affinity has a problem?

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Just now, abra100pro said:

Thanks for all the feedback!

I didn’t know about Fogra being "out of fashion" ;-). The prinshop guy said fogra was fine with them. (I must say, the guy is technical head of one of the largest printshops in Switzerland. They do fantastic and complex work). What I do not understand is that the CoatedFOGRA-profile ads yellow to a paper known for being at the yellow edge by itself... I must say that we didn't have these problems when I did exactly the same in Illustrator. Could it be that the profile from Affinity has a problem?

Never said Fogra was out of fashion, just the fogra 39 standard is considered obsolete and has been replaced with Fogra 51 and fogra 52 for coated and uncoated, wood free substrates.

No, the profiles you see in Affnity are the same as in any other program that uses ICC profiles, they are a set of profiles whose values are determined by the International Color Consortium.

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57 minutes ago, BofG said:

I'm always looking to learn more, could you explain how the customer in this instance could be involved in getting that consistency between coated/uncoated stock? I genuinely thought that would be down to the printer. Would you advocate that they set their document up in the smaller gamut of the uncoated profile to acheive this? I can't quite wrap my head around it.

Colour management seems to be one of those topics where the more I learn the less I understand :)

Same here - in my understanding it cannot be that hard - however I struggle with it again and again.

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Would you advocate that they set their document up in the smaller gamut of the uncoated profile to acheive this? I can't quite wrap my head around it.

Why on earth would you want to do that? You want your workspace in the largest gamut you can get otherwise you are working in a restricted gamut from the onset, one that is tight and will not allow any deviations. Let the printshop work out the best method. 

Just look at the difference between coated and uncoated profiles and then wide gamut RGB to coated CMY

Perhaps read up on ISO 12647-2/ offset for some answers.

coated vrs uncoated.jpeg

rgb vrs cmy.jpeg

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7 minutes ago, BofG said:

Well I wouldn't want to at all :) I just couldn't figure out how @Lagarto was suggesting the OP has a role to play in getting their coated/uncoated colours to be closer. The only thing I could think that could be done on the user end was to design in the smaller of the two gamuts, so therefore nothing in the coated version would be outside of what the uncoated delivers! Seemed like a bad idea to me.

Personally I'd use an RGB document and soft proof both uncoated/coated on there, maybe throw in an adjustment layer here and there if I wanted to modify to get a compromise middle ground on some colours, then just export still in RGB and let the printer handle the rest.

p.s. I spent far too long looking at that colour profile visualiser, such a neat tool. Pity it doesn't support v4 profiles - would like to see what my printer's space looks like.

I´m not figuring out how Lagarto came to his conclusion too. 

And I agree with you on the visualizer, you can spend waaaaay too much time.

 

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7 hours ago, Lagarto said:

In this particular instance the first question would be what kind of coated and uncoated paper is used and whether generic profiles for coated and uncoated stock can give predictable results when printing on those papers. In OPs reply (in related post) the blueness that was tried to be achieved was not PMS based, after all, but the color just appeared in the palette for other reasons, so the hex value x0975D0 was probably sRGB based (the default underlying RGB profile in Affinity apps), and it translates to C84 M50 Y0 K0 in Coated Fogra 39 (Photoshop; C85 M53 Y0 K0 in Affinity apps) and C89 M51 Y0 K0 in Uncoated Fogra 29 (Photoshop; C88 M54 Y0 K0 in Affinity apps) so there is not much difference in color values between the two profiles.

etc....

I enjoyed reading your statement and I understand where you are coming from. Very well written, it could be from right out of a text book and I can see that you have an understanding of the processes.

However it is from a textbook written in the 1990ties and RIP´s have moved on greatly since then. A modern RIP will now use the APPE (Adobe PDF Printengine) in the version 3 and 5 and no longer the CPSI print engine. If this were the case I would agree with you 100%!
The big thing is that APPE renders PDF directly without having to be converted to .PS first, this means that in a modern workflow you would keep to RGB in your layout application and convert to CMYK in the Adobe workflow, either in Acrobat or your imposition software or you can send your PDF file to the RIP, all three examples use the exact same engine and the exact same profiles and the exact same intents to render your files. This is the whole point of workflows, workflows that can cost upwards of 100.000 Euros, do you think that they are not able to handle RGB? 
Also since introduction of the APPE RIP printers are now embracing G7 as a standard (RGB/CMYK) and indeed printers are turning to actual printing in RGB, in fact Flexo has been RGB printing for quite some time.
But RIP technology is not the only place that has seen major steps forward; there have been improvements in ink to make use of a wider gamut and printing with extended CMYK gamuts is common.

Printing in CMYK has been around since 1900 and has had a good run, but it is becoming more and more dated therefore it makes no sense to create your work in CMYK, not in Photoshop or illustrator, Quark, Indesign etc. and certainly not in Affinity.

I understand, that there is no harder substance than the opinion of a printer or a designer when confronted with something new or something that goes against his or her common knowledge, I fight this day for day and it really is a irresistible force hitting an immovable object, but all I ask is to try and keep an open mind and... hey! Perhaps try it.

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46 minutes ago, Lagarto said:

 

We must have lived in parallel worlds then as the description of having to spend days beside a press machine happened in 90s. In 2001 something called PDF/X1a happened, which meant that basically everything that was in layout no matter how composed was converted to DeviceCMYK. At that time we still also prepared images separately for CMYK and manually adjusted them in Photoshop (which was a standard workflow supported already in PageMaker and later InDesign by allowing switching between the modes by using separate folders; Quark had extensions that could apply automatic adjustments along the conversion process).

That changed with the development of InDesign (released in 1999) and workflows changed so that images were largely left in RGB mode, and the whole printing process became to be governed by ISO standards and color profiles. PDF/X standards developed so that in PDF/X-3 (initially 2003) you could include also managed RGB content as along with included CMYK intent, and in PDF/X-4 (starting from 2008) also unflattened transparencies. Majority of printers that we used still required PDF1.3 based export PDFs in full CMYK (+ spots). No matter which workflow and PDF export method was used, a CMYK target was required if there was anything left in non-device CMYK color space, and all native graphic and text would be converted to CMYK according to the specs of the target profile.

Many printers today require that PDF/X-based standards are used when producing the print PDFs, and they all convert native colors (graphics and text) to CMYK. This is also the default when using press vanilla in InDesign. Last time I had CC-based InDesign rented this had not changed, and QuarkXPress at least up to 2018 version works similarly. In Affinity apps the default color mode for all “Press Ready” templates is CMYK, as is the default color mode when choosing PDF (press ready) at PDF export, which means that all RGB-based definitions in native objects and text will be converted to CMYK according to the CMYK target profile, and if none is or can explicitly be selected, the failback U.S Coated Web v2 will be used.

Not converting to CMYK, or using a RGB document color mode (or RGB color definitions for native objects) in press-targeted jobs is possible in all these apps, but it is going against the grain (defaults) and working in a non-standard way. You can of course do so, but then you need to have an agreement on doing so with the printer. Not doing this is not old-school, it is still the industry standard. 

Designing and creating in RGB is a totally different thing so it is clear that RGB is used when creating anything in e.g Photoshop. And photos and other raster images stay in RGB when placed in the layout, as well.

 

Basically then we are in agreement, images stay in RGB until it enters the workflow, as all stations use the same Adobe engine so it really doesn´t matter, you will generally import your RGB into your Layout and export a PDF output which is fed into your workflow with imposition and prefilght or directly to your RIP.

It does not go against the industry grain when your Affinity is set to RGB instead of CMKY and I still believe that you should work in RGB when creating your art, which was the topic of this great thread. 

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